Engine failure , why we had to rebuild our 8V71TA Detroit Diesel after 625 hours

Here is what we found out after tearing into our 8V71TA 2 stroke Detroit Diesel that was rebuilt only 14 months , or 625 hours ago.
Since having it rebuilt in January 2019, we experienced loss of power( less than before the rebuild) , oil leaks, blowby( oil coming out the breathers) low turbo boost, and multiple turbo failures.
What caused all of this, 2 things, first the fuel system was not pressure tested, leading to damage to bearings and turbo. Second the liners were too small for the engine bores.
#enginefailure
#8V71
#detroitdiesel
#busmechanic
#gmc
#gmcbus
#tinyhomeonwheels

[@robragle]

Wasn’t this a bus grease monkey build?

[@LacroixCruiser]

Yes

[@dmc2554]

@@LacroixCruiser Oh dear............My bubble of perception about that guy just popped....it's sad

[@LacroixCruiser]

Unfortunately his inability to take a moment and refer to the Detroit Diesel service manual cost us a lot. All the mistakes that were made could have easily been avoided had the service manual been followed. The gentlemen that mentored me in rebuilding the engine per factory specs has been doing them for over 50 years. He doesn’t do anything without referring to the manual. His knowledge is so profound of these engines and manual, that every day he would tell us what needed to be done, and what page in the manual the instructions were on. In the early stages of disassembly we found a thin flat piece of metal about 1/4” by 1/2” with a slight curve to it. He was able to identify exactly where it came from at first glance. At that point we knew we were in a different and better league.

[@misters2837]

@@LacroixCruiser I would say Bus Grease Monkey has some good videos about road side general repair, and rack/injector issues... But as an engine builder...he doesn't have the place to do the major overhaul type stuff... There were some things I asked him that I wasn't sure of (like switching from 2V to 4V heads if certain things need to be changed)...but those are things that aren't in a "manual" they might be in a "TSB" but these engines almost pre-date paper...(I am kidding)

[@tageuhl6422]

@@misters2837 having traveled the US and Canada as an entertainer coach driver, I can tell you the Bus Grease Monkey is very competent compared to some of the clowns we had working on our equipment. I only had Bus Ride magazine’s repair shop guide or a local yellow pages to find repair and maintenance most of the time, there was no internet for reference. It was the early 80’s. Coaches are not getting any younger and earlier botched repairs are so common. My one overhaul was at a Detroit dealership in the Quad Cities on recommendation of my main mechanic in Chicago. They were surprised to see the modifications Greyhound had done in their engine shops, as it was bought from and rebuilt by them. Engine repair and rebuild should be handled with the best sources available since machine shop skills are used.

[@tjlovesrachel]

Love the video... damm the music

[@user-ff5ge7hx2c]

You guys clearly don't know what your doing

[@johngillon6969]

I did a rebuild in my 371. Engine was build for ww2. It took me a long time as i had never worked on a diesel. I had a couple of friends that gave me a students manual from the 40s and another from the 80's. the engine had been updated in the past and was a combination of the two. I studied those manuals and watched youtube video's like yours. and believe i got it nailed. watching your video scares me too much, thinking about those vibrations screwing up my bearings. Thanks for coming clean about what a bad job that rebuild was. When i was done and my boat was running like it should i realized, i am glad i have a small 371. it was allot cheaper to rebuild than a 8V71. Wish me luck with my engine.

[@hoost3056]

I am so sorry to see this. I have been in trucking for a long time and have had my share of pain. Finding the old timers that still do it well is the key.

[@LacroixCruiser]

Thank you

[@johnathan450]

Wow the chain reaction of all the metal on metal parts wearing out I expected. What I did not expect to learn about was how the turbo was eaten up.

[@chuckdykstra3020]

Great job putting this together. It is a shame you are having to deal with this mess. Thankfully you have a true expert on these engines available to help you get to the bottom of your problems.

[@brownh2orat211]

Learned to rebuild these in the Navy back in the 80's then had my own marine business doing Marine Diesels. Did lot's of 71's, 53's, 92's and 110's all were the marine version, same engine just with a lot of extra junk on them. Still have all the special tools for them, doubt I'll ever use them anymore, not a lot of 2 stroke Detroit's out there anymore!

[@LacroixCruiser]

Thank you for your service!

[@BusNit]

If you want to sell those unused tools, let me know!

[@FetKiller]

Thanks for video! Love the Detroits. Little bit of feedback on the video - the background music is distracting.

[@LacroixCruiser]

Thank you

[@philipkeiser4442]

Damn sorry to hear about your motor. Thanks for sharing your unfortunate experience.

[@LacroixCruiser]

Thank you for watching

[@SubOnly]

Thank you for sharing such a detailed breakdown of the fail points and reasons. Very helpful.

[@LacroixCruiser]

Thank you

[@brucefay5126]

Wow, that turbo impeller was really toast. So sorry you had all of these problems with the engine. Having had a DD8V92TA DDEC II in-framed in the second half of 2017 due to coolant in the oil, and then having a failure in one of the heads in spring 2019, I know how frustrating and expensive engine failures can be. You seem to be in good hands and I am looking forward to seeing more about this work, but especially to seeing you back on the road. I really hope that you and Sylvie get to stop by our BW host site someday.

[@VHP7044]

71 series engines are what are referred to as dry liner or dry block engines. It is critical that the liner to block fit is within specifications. If the liners are loose they cannot transfer heat from the cylinder liner to the block. The old rule or thumb is it must not loose more contact area than the size of a quarter. The block can be salvaged by boring it and adding oversize liners. Fleets such as greyhound would successfully rebuild the 71 series engines several times with success. It is not uncommon to find a old greyhound engine in a salvage yard with a rebuild tag showing .040 under size bearings and .040 overbore. Beware of old bus engines if you want to use it for something else as it may be reverse rotation.

[@randymagnum143]

Swap the cams side to side to reverse rotation, i believe. The engine is 100% modular.

[@twofeathersrv]

2 or 3 thousandths

[@TATEXPRESSINC]

Shoutout from TAT Express out of Hutchins, TX

[@macelius]

The thumbs down must be from the last 'mechanic'.

[@dehoedisc7247]

Yes, there must be a wrench-twister involved in the previous repair/rebuild who may have played a part in this story.

[@howardgaither8759]

If they don,t hone the black out of the cyl.block & have bright iron for the cyl. liner to fit & have metal to metal contact they will gauld another piston, bee n there & done that. This mechanic wouldn,t make a good lawn mower mechanic.

[@macelius]

@@howardgaither8759 I hope you're not talking about the guy who rebuilt it this time (Yvan's just the customer), He's been rebuilding detroits since long before there were V models and most old timers still alive these days were in diapers. It got honed, measured, fitted, and measured again, this time it got done by the book and proper.

[@LacroixCruiser]

This time everything was definitely honed with a micrometer adjustable hone, measured many times, and the fit adjusted to within Detroit Diesel specs. Yes the mentor that helped us is not only a fountain of knowledge when it comes to these engines, but also a great human. He has helped many people in similar situations to ours. It’s unfortunate that he was camera shy, I would of loved for him to take the spotlight.

[@howardgaither8759]

I too was an old time Detroit Diesel mechanic, Detroit Diesel Service Craftman Guild member, built many engines, wish i had kept a record. I was not talking about the guy that repaired it last time, just the baling wire mechanic that made the mistake of putting a loose fit liner, & all the other mistakes when he assembled it.

[@11thhourcustom]

Yikes! That thing was waisted. I'm sorry you have to go through that. Great Video though 👍.

[@terriwinn6806]

Another informative video . thanks .

[@LacroixCruiser]

Thank you for watching.

[@yo3604]

This video was more educational than a training one, you have in your hands the results of making some little mistakes or as somepeople. Can say it's an stupid thing......but as a result we can see how important is in long terms those little things, guys I'm sorry about you're need to rebuild again you're engine, but this way ur video goes so instructive, great video simple but go directly to the important things, go ahead my friends, really nice channel!!!

[@LacroixCruiser]

Thank you.

[@yo3604]

@@LacroixCruiser welcome , keep doing it great!!! I love you're channel and its for special reasons!!! You're no ordinary guys, you're simple people who enjoy and enjoy more to share you're experience in a very very gentle and understandable way

[@maureenmillard4241]

Check out Dangar Marine ,Stew has found a new spanner man, his first rebuild failed after a short time as well!!

[@DangarMarine]

That's terrible advice! ;)

[@michelscalabrini5490]

​ @Dangar Marine I saw all video of Dangar Marine with Adrian and to bo honest I learn a lot!!!! Good job guys.....

[@danielneilson867]

@@DangarMarine typical Aussie humour, I’ll drop a sixer out next time I have the boat out down there. (from Newcastle)

[@edward9862]

Great video! TY for the information! ☮️ 🕊️

[@LacroixCruiser]

Thank you for watching

[@terrymjinks]

Very educational.

[@Ozzcaddy]

G'day Yvan, enjoyed the detailed explanation of why the engine has failed and why the turbo needed rebuilding 3 times. Like anything that requires repairing by someone else, is finding someone who has full knowledge and experience with that type of engine. Having the oil holes of the rollers facing the incorrect way is a rookie (apprentice) mistake, not an experienced mechanic. Wish Sylvia and yourself safe and many free uninterrupted engine mileage. Cheers from Down Under.

[@porkbuttrocks]

Or it could be from driving on bad injectors. The lifters were backwards, but they didn't have anything to do with the root cause of this engine failure.

[@LacroixCruiser]

The root cause was shoddy workmanship from a mechanic who apparently can’t be bothered to do things like take measurements, read the explicitly detailed Detroit Diesel manual, nor follow up when we reported issues the day after it was rebuilt.

[@porkbuttrocks]

@@LacroixCruiser I am no fanboi, but you are conflating a few different things. Why did the engine need the first rebuild?

[@LacroixCruiser]

The first rebuild we did as preventative maintenance, not because it needed it. I much prefer investing in prevention than paying for a cure. It had way more power before the 2019 rebuild. Since then we had been suffering in the slow lane with excessive blowby, poor cold weather starting, and a mechanic who was doing anything to avoid us. We even drove to his hometown and waited 2 weeks for him. Every other day we got another excuse why he couldn’t make it , and he would be there in 2 days. After 2 weeks we had to leave to work.

[@bobsmith2637]

Wow. Glad you were able to luck out and find a much better rebuilder. GM 2-strokes of all kinds are terrific, reliable engines. At work we still have hundreds of locomotives with the much larger EMD engines, both blower and turbocharged. They run forever, many have gone decades since their last complete rebuild, even though railroads are terrible at doing regular maintenance.

[@LacroixCruiser]

Yes we found a great mentor, the engine is now very happy.

[@RJEvans-hn9ci]

Good video Yvan with one caveat. I heard the bus Yoda's voice briefly but I really hoped he would make at least a cameo appearance. Say hi for me.

[@LacroixCruiser]

He’s allergic to cameras...

[@bartdegroot4826]

Cut the music out when the man is talking.. it's only distracting and annoying..

[@randymagnum143]

My dad had a 6-71 bored for oversized liners one time, and direct drive conversion on the blower. Ran like a clock.

[@timothywood4402]

We just lost our 8-92 natural after 62,000 hours 😊41 yrs old

[@LacroixCruiser]

That’s not fun

[@rberry1964]

obviously the guy who done this didnt know squat about dd 2 strokes. i've rebuilt several over my 40 yrs as a mechanic and you must use the manual on these motors. they are a simple and complex at the same time. the fuel system alone is enough to keep most guys from ever touching one of these.

[@rogeryoung2049]

You definitely had fuel dilution on the rod bearings. The roller followers oil hole faces away from the cam on installation. The scored liners also show fuel dilution and overheating

[@scotteverett1786]

Hope you recovered the costs back from the original rebuild

[@LacroixCruiser]

No

[@uliwehner]

that is very disappointing to see. Hopefully your problems are resolved for good now.

[@LacroixCruiser]

Yes they are

[@ThePaulv12]

Dangar Marine in Australia had big issues on his 4-71 built by an apparently reputable shop. It needed a full rebuild after 20 or so hours. He found a Detroit Diesel 2 stroke wizard called Adrian that is a great character, has all the tools and is thoroughly across Detroit 2 strokes. Even his Blue Heeler dog is called Detroit. Adrian too is a backyard operation but a good backyard operation. The gudgeon pin plugs were hammered in with a punch rather than the correct tool and all of them leaked. They ended up having to replace all the pistons and liners because the liners were not shimmed correctly and sat too low and rattled around. At the time Adrian checked the blower clearance and that was no good either, all the injectors were incorrectly set as was the rack and governor.

[@LacroixCruiser]

Very unfortunate, like our engine, had the person rebuilding it taken the time to read the manual, all would have been fine.

[@cobrasvt347]

Good ole cross head pistons 🤙

[@ruxoneto6560]

Who ever rebuild the engine should have known that all most all 71 series with high hours sould strip block to bare & machine line bore in block to over size lines, i have pulled engine apart that have high hours with cam rollers installed backwards & no cam damage . as for wrist pins wear , i think it is junk aftermarket parts not over torque of bolts..

[@soillife1]

You know your stuff Rux 😉😁

[@frontagulus]

They're very easy to rebuild but like the man said, follow the instructions in the book - they're detailed and sufficient to do it right.

[@YouTubeviolatesmy1stamendment]

They are very sensitive to mistakes you have to follow the book exactly

[@LacroixCruiser]

They are sensitive to gross errors and negligence, not a little mistake.

[@barryphillips7327]

Generally speaking on a rebuilt engine the FIRST ten seconds of it running is the critical in it,s life!

[@LacroixCruiser]

Exactly, and when 3 fuel lines are spilling diesel into the oil, it’s never a good day.

[@jddees24]

Mine was just rebuilt and he said it ran fine at idle but when he gave it some fuel it made squeaking or squealing sound, he tried replacing rod bearing then it still made noise so he is tearing it back down tomorrow - I’m wondering what his tech may have done wrong and will this cause me future problems

[@LacroixCruiser]

Definitely not a good situation, I wish you the best.

[@DrewFixIt]

Any comments from the shop that did the last repair?

[@winckler100]

Hi, amazing video and thanks for the learning. Which book or literature do you have used? the one you show in the video. Tkank you again

[@LacroixCruiser]

The Detroit diesel manual.

[@georgedemas7718]

that #3 liner was too loose. I would have used a #4 or honed the bore and used a .005 over liner. i didn't catch in the video where your fuel leak was. everyone wants to be a diesel mechanic.....lol. i built my first detroit 45 years ago . i learned from and old timer that had worked on them his whole life. my shop specializes in 2 stroke detroits and i love every minute of it.

[@LacroixCruiser]

We installed a # 4 there when we rebuilt it. Unfortunately the previous mechanic just went by what was stamped on the block, he didn’t measure the bores. 2 of the injector cross over tubes hadn’t been tightened on initial start up, and test drive, leading to the engine making oil.

[@georgedemas7718]

@@LacroixCruiser that explains the oil dilution. i can't even begin to tell you how much work these wannabees have created for me through the years. i keep a #2 and a #4 liner on the truck to find the right size upon teardown. if the # 2 is loose and the #4 is tight then it takes a #3.

[@LacroixCruiser]

Great plan.

[@julianospina7816]

Buena compañero sería posible que digas cuántas vueltas devo de dar a las roscas del tornillo de alta potencia sin carga para que quede a punto tengo un motor 6v92t te agradezco y Día te bendiga.

[@bobsillas3553]

tank a lot

[@jddees24]

Mine was just rebuilt, when they got it back together said it made a squealing or squeaky sound when gave it fuel but sound fine at idle. They found 1 bearings upper/lower scored replaced that still made noise tearing it back open tomorrow~ ideas??

[@soillife1]

This issue certainly takes the fun out of Camping 🏕 🙄 Traveling in your Coach, Bus 🚌 🤣

[@LacroixCruiser]

For us it isn’t just a weekend camper, but our home.

[@jw4620]

Oh my! That's a mess! I'll have to look and see who built it.

[@user-ff5ge7hx2c]

Im telling you that when you dropped that liner in its way to loose, you should have resistance when you push them in

[@LacroixCruiser]

Agreed

[@stevecarlisle3323]

The main problem is you have had mechanics that do not know DD 2 stroke engines. A properly fit liner never drops into the block like your video shows. I have rebuilt 71,s and a few 110, s for over 30 years.

[@user-ff5ge7hx2c]

That's right, a thumb fit is perfect but I have had to push a lot harder

[@kleetus92]

So who was the 'mechanic' that rebuilt the engine?

[@gcflower99]

kleetus92: See comments above...Bus Grease Monkey built it.

[@detroitgarage9430]

Sorry if you've already mentioned, but were you running SAE40 or 15W40 in this engine? Thanks.:)

[@LacroixCruiser]

Mobile Delvac 40w

[@cwvanhagen]

Was that a Scott Cosby rebuild? If so that type of damage is not surprising Good luck with the rebuild you at the right place now.

[@LacroixCruiser]

We definitely are in the right place, your suspicions are confirmed.

[@Dunno513]

Oh man.... you should really list the rebuilder so others who used them can get it sorted now vs the side of the road.

[@brownh2orat211]

Read up on the early history of the 6-71, was designed as a one use engine to get landing craft to the beach never really designed for longevity but they ended up being very reliable and long lasting, just catch all the dripping oil and pore it back in the crankcase, will run for ever!

[@allanholiday441]

Great Video! Learned a lot. Hope you have some recourse. This makes all mechanics look bad.

[@LacroixCruiser]

The person who did it not only didn’t offer to fix the issues despite many occasions to do so( we even drove to the city he lived at to meet with him, waited 3 weeks and he never showed up), but offered no help.

[@allanholiday441]

@@LacroixCruiser it's time to get legal advise.

[@MrAli171]

I would have a total sense of humour failure with people who rebuilt it

[@scottyjones27]

Is they not a copper ring that goes a top liner and between head ???

[@LacroixCruiser]

There are shims that go between the liner and block if required.

[@detroitgarage9430]

Great video.:) Be like new again after your done with it.:)

[@JeffinTD]

Expensive little oopsie doodle. Sorry to hear that. Looking at it I wonder if there was also imperfect head gasket sealing, maybe liner height problem as well.

[@LacroixCruiser]

All I can tell you is the one who rebuilt it in January of 2019, didn’t measure anything apparently.

[@JeffinTD]

Hopefully they stood behind their work. Not many 2 strokes still around around in my neck of the woods, and (like points and carburetors) I’d guess not too many mechanics working today have experience with them. Anyway, greatly enjoying your channel. Keep up the great work.

[@LacroixCruiser]

Thank you, and unfortunately no he hid from his responsibilities.

[@donmunro144]

Never had much love for the old Detroits. If all that noise could be turned into power, then you'd have something.

[@LacroixCruiser]

But it’s such a beautiful sound

[@JohnSmith-hr3gv]

Hi Yvan, I am not entirely sure about this, but should there not be caps on the pistons where the gudgeon (wrist) pins are? These are there to prevent blow-by (I think that is the term).

[@LacroixCruiser]

Yes, we have press in caps Now.

[@georgerenton965]

Gudgeon pins !!!! Have you been talking to my dear old dad ?? Haven’t heard that term in decades. You wouldn’t happen to have a shifting spanner ? LOL.

[@JohnSmith-hr3gv]

George, I do have a shifting spanner. I am guessing you are either from the UK or Australia.

[@VHP7044]

John Smith the wrist pins are sealed with thin metal retainers that should be vacuum tested before assembly. There is a seal between the trunk and crown of the piston for sealing. Good design but the engine must be inspected and assembled correctly. Also bus engines in the US typically are rebuilt beyond normal engine design limits. If you find a retired coach engine in a salvage yard leave it there as it has served its time. I have seen .040 undersized bearings in some of them.

[@LacroixCruiser]

VHP7044 correct, ours held over 20 inches of mercury for as long as we left the tool attached.

[@jeroenschuuring6060]

How to learn, the expensive way 😉

[@LacroixCruiser]

Agreed

[@TheCRTman]

Damn this is terrible! The whole situation with the liners being the wrong size is a real facepalm moment. And not testing the fuel system pressure too.....

[@LacroixCruiser]

Unfortunately yes, 2 simple things that could have saved us so much grief and Money.

[@2secondslater]

I would want a tighter fit on those liners, you should also give the liner bores a quick hone when fitting new liners

[@LacroixCruiser]

The bores were honed, and the liners are within Detroit Diesel specs when measured. So far since the rebuild it’s running perfectly.

[@2secondslater]

All good mate, if it is running good then that is all that matters, I only made the comment because I have built many Detroit Diesel 2 stroke engines when I worked for Detroit Diesel for 10 or so years. I could see your hone didn't touch the low spots in the parent bore because there was still carbon marks visible, the way the liner slid into the bore without assistance would have been a no go for me. Just some little things I picked up on, not criticising pointlessly. Great vid anyway, cheers from Western Australia mate.

[@timandres6410]

Yeah those +3 liners look pretty loose to me. Ideal fit was when they could be pushed down by hand. If they fell all the way in by hand that was too loose.

[@kevinoscarson2941]

Yup, we always put them in with a dead blow and a soft block.

[@michael931]

Why no interference fit?

[@ArifKhan-xw8uj]

head torque specs

[@Tchristman100]

When I bought my transit bus, the 8V-71 had been rebuilt by Portland, Or Metro. But, same thing, loosely fitted cylinder liners. Pulled the engine and had the block bored by .010 and over sized cylinder liners with standard interior bore installed to reuse the pistons. Then everything has been working great now for over 40,000 miles-even with turbocharging the engine with NA pistons!

[@andrewking9761]

Don't mean to be smart arse but the turbo pistons should be used they have a slightly lower comp ratio at 18:7 to 1. But being a Detroit you might get a few hundred thousand miles out of it as they are the toughest engines ever made.

[@LacroixCruiser]

The pistons installed are the correct pistons for a turbo charged engine.

[@Tchristman100]

@@andrewking9761 Actually NA pistons are 18.7:1 and turbo pistons are 17:1. My 18.7:1 pistons are two piece with the tight transit rings. We only went to 7G75 injectors, added the bypass blower, used the 12.7 Series 60 turbo that has a waste gate set at 15psi, and most importantly have an air to air intercooler in front of the radiator-first 8V-71 my mechanic did. He liked it so much, he did 5 more buses with air to air intercooling on the 8V-71's. It REALLY wakes up the engine. Puts out 375hp and 1125lb/ft torque. If you did have a TA block, you could use 7G80 injectors and get 400hp and 1,200lb/ft torque.

[@wilson502]

Fascinating video as always Yvan, thats pretty drastic wear in a short period with an engine like that. I wanted to ask, if you have ever thought of converting your bus to an electric drive-train in the long term future as battery technology and charging infrastructure improve and become less expensive. Cheers

[@LacroixCruiser]

Yes we inquired about it at SEMA last fall, it’s not quite feasible, yet.

[@wilson502]

@@LacroixCruiser makes sense. I would imagine that is still about 5-10 yrs off from being a feasible conversion as by that point batteries will be well under $100 kwh, and charging infrastructure will be far better by then as well.

[@davidcopeland2735]

Another rebuilt and parts oh my.

[@LacroixCruiser]

Luckily for us a very experienced bus owner and Detroit Diesel mechanic took us in and mentored us. We only had to pay for parts.

[@TheRoguelement]

Hey Pop isn't blow by from piston ring excessive wear ? I'm.ptetty sure I learned that in grade school .but who did you let rework this motor before some child who said he knew how ?

[@LacroixCruiser]

Typically yes, in this case I couldn’t find a better way of explaining it. The cylinder liners that were installed by the previous monkey were 2-3 sizes too small. They had so much space that oil was flowing around them.

[@AllianceB95]

Very informative, many thanks for sharing this with youtube. Now if the Detroit engine was to have some 'issues' again, perhaps it would be an idea to call Bus Grease Monkey, he is the specialist in all real Detroit engines. Kind Regards from The Netherlands (Europe) Bjorn

[@LacroixCruiser]

He is the one who rebuilt it last year, he’s a KZbin specialist more than a Detroit diesel specialist.

[@JimBronson]

@@LacroixCruiser ouch

[@jddiesel7409]

Oh the irony 😂

[@krugtech]

those missing tips on the turbo turbine were burned away, not knocked away me thinks

[@jefflittle4013]

Probably a combination of both. The carbon deposits adhere onto the fin and create a hot spot, like a chunk of charcoal. That hotspot then melts the fin.

[@tageuhl6422]

@@jefflittle4013 very common for charter coaches, that long periods of high idle would build up carbon and then running at highway speeds, we would be spitting out sparks visible at night.

[@Edypaul636]

That Engine looks like it got hot to me !

[@LacroixCruiser]

It never got hot, but doing the initial start up with fuel leaks didn’t help.

[@crazytrucker2376]

What about oil pump and pickup tube? I have the same motor. 8v71 in my 66 peterbilt. Motor only has 200k miles on it. Sat for over 30 years. Opening it up tomorrow to see if I should build it or just repower it with a different motor

[@LacroixCruiser]

The pump and tube were in good shape. Repowering might be easier, but no engine sounds as good as an 8V71 at full song. I’ve been around race cars all my life with high power V8 engines, they sound great, but a 2 stroke Detroit has them beat.

[@crazytrucker2376]

@@LacroixCruiser motor is dripping oil out of the blowby and smoking bad. No miss no knocking

[@LacroixCruiser]

Too much idling can cause that.

[@TheGoodbiker]

that looks like a part of a valve went through the turbo

[@LacroixCruiser]

Tons of carbon due to loose liners. The valves were in great shape thankfully.

[@richardcranium5839]

to me that liner dropping in so easy didnt look right. a good fit they will push in all the way.

[@mikemotteberg3527]

If a person does not know what they're doing, Don't do it !

[@LacroixCruiser]

Some unfortunately do.

[@MitzvosGolem1]

Always Dyno a rebuild 8 hrs all loads get paper work. All Marine engine s I have Dyno before installing. Oil samples pressure temperature hp torque crank case pressure all tested recorded.

[@haaseuros9789]

I knew it! It's the Pokémon selection song from Pokémon stadium 2 on the Nintendo 64! No idea how I know that from 10 plus years ago.

[@LacroixCruiser]

It’s part of the included music in I Movie

[@alleycatvietnam]

I assume that someone else did the re-build? Have you ever sent your oil out to be analyzed?

[@LacroixCruiser]

We send a sample at every oil change. After the rebuild in 2019, they never came back with great results. The engine was rebuilt in January, and by February we knew it had to be done again. This time Sylvie and I rebuilt it with the guidance of a veteran Detroit diesel mechanic, and the manual. So far we have driven it almost 4000 miles, and all we have to report are smiles.

[@alleycatvietnam]

@@LacroixCruiser I've used www.blackstone-labs.com/?session-id=tv3emc5533xw0xnhifv14ln0&timeout=20&bslauth&urlbase=https%3A%2F%2Fwww.blackstone-labs.net%2FBstone%2F%28S%28tv3emc5533xw0xnhifv14ln0%29%29%2F Several times for my 2002 VW GTI 1.8 T with 282,000k I found thier reports to be very through...Keep up the Good Work...

[@LacroixCruiser]

After threatening him to expose his poor ethics and work he reimbursed 25% of the original invoice. While not enough to cover the cost of fixing his mistakes, it was a gesture in the right direction. I know he isn’t well off because he has to beg for money on patreon, and go fund me to pay for his lifestyle.

[@LacroixCruiser]

Route 66 Texas that’s great. I was lucky to have been coached by someone similar to your grandad . Straight shooter, who’s been rebuilding Detroit’s for over 50 years. He couldn’t do the wrenching himself, but leant us his mind, manuals, shop, and tools.

[@LacroixCruiser]

You’re very lucky, appreciate every second you have with him.

[@tomcurry556]

Wow

[@cobrasvt347]

Lifter oil holes always face away from the head.

[@LacroixCruiser]

Apparently not everyone saying they are Detroit Diesel “experts” can read the manual.

[@graemegaerth14]

As they say hindsight is a great (albeit expensive) teacher. It is so disappointing when you put your faith into someone you trust is going to perform to your expectations. . I have followed a few of this guys shows and thought him to be a capable mechanic, maybe best he stay away from rebuilds. Silly mistakes by someone obviously out of his depth. All of this does not help you or your bank balance but you will have confidence moving forward. unfortunate but good viewing

[@LacroixCruiser]

Thank you

[@ScottBennettMusic]

Wasn’t this a Scott Crosby Grease Monkey rebuild?

[@LacroixCruiser]

Yes

[@castirondude]

I thought the dry fit liners were supposed to be so tight that you have to press them in and out..? I haven't seen people just sliding them in by hand.

[@LacroixCruiser]

Too tight isn’t better than too loose. These fall perfectly in the middle of the clearance range in the manual.

[@castirondude]

@@LacroixCruiser ok. I thought dry sleeve engines were always really tight like this kzbin.info/www/bejne/bqXKYpWlqt5kq7M but after some more searching I see other engines that have them not so tight.

[@LacroixCruiser]

The ones in that video are definitely tight.

[@eugeneoreilly9356]

The only dry liner engine I'm familiar with is Perkins and you have to put them in dry ice for 20 mins to shrink them so they slide into the bores.

[@kevinhornbuckle]

I don't know who rebuilt your engine improperly. It seems you have the basis for a full refund at the very least. Additionally all the costs you suffered attempting to remedy what you were led to believe was a good rebuild (turbo replacements, lost oil, wasted fuel, etc.). I hope you are able to obtain recourse without having to go to court.

[@donraptor6156]

Do you really believe you can get a dime from the builder? All the post dissembly and cause to effect is nothing but a guess! There is no proof!

[@edotrucking1]

hope you check Oil Pressure and the Injector on this Engine , Look like over fuel and no good oil Coase of to much fuel or some thing ales, This Engine have lock of Lubrications I believe

[@LacroixCruiser]

Unfortunately the technician who rebuilt it didn’t check either, that’s why it had to be rebuilt.

[@jefferyepstein9210]

It’s like an autopsy for the engine

[@LacroixCruiser]

Yes, interesting to note what caused an engine to fail in the first 10 minutes of use.

[@douro20]

I didn't know they had crosshead pistons in 71 series engines.

[@rosscollins2910]

I’ve seen them in 8V71T engines 350 HP.

[@LacroixCruiser]

This is an 8V71TA

[@andrewking4885]

They've had them since 1975

[@briananderson3801]

And the blower ,,,just make sure you re time the blower when you put it back together

[@LacroixCruiser]

It’s all back together and has 4000 miles on it so far, running like it should.

[@ruxoneto6560]

What B/S are you trying to pull (timing the blower ??? ). how do you time the blower,

[@LacroixCruiser]

A blower is timed by shims behind the drive gears. To get proper blower clearance it’s important to check and adjust as required. It’s all very well explained in the factory service manual.

[@briananderson3801]

With the timing marks on the blades inside the blower

[@ruxoneto6560]

You are talking about setting the clesrance on blower, that is done when assembling the blower & setting the orentation of the left rotor to the right rotor.

[@TheMatrixgod]

where are you lcated?

[@LacroixCruiser]

We are in Quebec

[@ronayotte3571]

Is this one of the reasons for getting a new bus?

[@LacroixCruiser]

No, the MCI 102DL3 chose Sylvie

[@Joeilliano]

What state do work?

[@LacroixCruiser]

We are in Quebec

[@The1856gourd]

Cam looks ok, when the roller wear into the cam they do not effect the outer edges. The marks you see on the cam are micro pitting, this is not a warrantable problem, actually it’s not a problem. Hard to see on video but have cam checked before you wast your money. The loose liner is not causing blow by. I don’t see the rod bearing wear you are talking about? The wrist pin bushing looks normal.id look for debris entry somewhere, carbon did not destroy that turbo.

[@cobrasvt347]

I haven't seen lifters set that crooked in years. 😩 Sad thing there

[@LacroixCruiser]

Agreed

[@ruxoneto6560]

When cylinder head is installed the cam follows will self center !!!!

[@gabe1254]

How much did that “rebuild” in Indy cost ya?

[@LacroixCruiser]

Too much.

[@gabe1254]

@@LacroixCruiser life bites ya sometimes. Bigger and better things and all that . . Really digging the MCI, stay healthy my friend

[@LacroixCruiser]

@@gabe1254 thank you, you sometimes must pay twice to learn.

[@Hitman-ds1ei]

Not convinced you identified the source of oil correctly as would see cracking at top flange if too loose and loose liners is not an oil source but blower seals more likely

[@LacroixCruiser]

Blower was rebuilt and is bone dry, no oil coming from it nor the turbo above it. The person that guided me in rebuilding the engine has over 50 years experience rebuilding 2 stroke Detroit Diesel engines. These findings are his, but he’s very camera shy.

[@Antipodean33]

Was this your own doing or was a "professional" at fault?

[@LacroixCruiser]

A professional did this to the engine. Subsequently we rebuilt it ourselves and it’s been going strong and leak free for over 3 years now.

[@mikejuzenas93]

Sorry to hear this happened - its funny that Stu over at Dangar Marine also had his Detroit rebuilt and then had failures afterwards (in less time that yours), resulting in a full second rebuild. I guess the conclusion is the mechanic who does the work really has to know their stuff or big bills result, never mind down time. Starting to get scared of these series of engines, they look way more complex that "standard" diesels ...

[@LacroixCruiser]

Nothing to be afraid of. These engines were built for many decades and we industry standards in the trucking, bus, industrial and marine industries. To rebuild them properly simply the mechanic be humble enough to follow the manual. The mechanic who mentored me on this build, despite having over 50 years experience rebuilding these engines, refers to the manual for every step.

[@hudsonhawk0016]

There must have been some indication that the engine wasn't rebuilt properly from the beginning. The engine was run too long in this condition all be it for 625 hrs.

[@LacroixCruiser]

There were signs within 5 miles. From there getting the previous rebuilder to take a look at what he did was an exercise in frustration. After a year of poor communication and excuses we gave up getting any help and decided to do it ourselves with the help of someone who has been rebuilding and repairing 2 stroke Detroit’s for over 50 years.

[@hudsonhawk0016]

@@LacroixCruiser So the end result was a completely botched rebuild by an unqualified mechanic. These engines are not difficult to rebuild by even an average mechanic that knows how to use measuring tools and can read. What a damn shame.

[@LacroixCruiser]

hudsonhawk 001 unfortunately the mechanic is KZbin certified, I believe that precludes him from reading the manual...

[@hudsonhawk0016]

@@LacroixCruiser KZbin certified, that says it all.

[@wazza33racer]

exhaust gases leave an engine at supersonic speeds........any 'chunks' will absolutely mess up the exhaust turbine.

[@LacroixCruiser]

For sure

[@ronbros]

sounds like it was an original factory remanufacture , and they commonly bore All bores over and fit oversize OD liners, after lots of years some just but a set of NEW standard size liners, slap it together never measuring OD sizes!

[@LacroixCruiser]

The block is a 1984 , it was rebuilt in the 90’s then in 2019 where this happened.,

[@tylertylerdurden194]

I work at a Detroit reman center, these 2 cycle engines can be finicky

[@LacroixCruiser]

Yes, but fun as well.

[@kennsaunders1690]

Love the video but in the future please leave out the background music. It takes away from your delivery.

[@LacroixCruiser]

Unfortunately once uploaded to KZbin it can’t be re-edited. This was one of my first videos.

[@cesarruiz2024]

Some times you learn the hard way,unfortunately

[@LacroixCruiser]

Unfortunately yes, hopefully the person that did the damage has learned from this video.