Diesel Blow-By Field Testing on EIGHT Trucks!

In this episode, we put 8 different vehicles to the test as we measure blow-by back to back! With the help of J Tech's specialized tool, we tested the pressure flow in each engine and dived deep into understanding the results. Then, we come up with a solution to correct the pressure offset using a crankcase filter.
Follow along for a detailed breakdown of our testing process, what blow-by means for your engine, and how the crankcase filter can make a big difference!
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[@OzarksWildman]

I feel like my 7.3 leaker would blow the competition away 💨

[@chasewebber4316]

Got a 12v Cummins that’d give u a run for your money

[@bfields1448]

I had a 99 f550 4dr 6spd. Started blowby and I sold it😂 only had 150,000 mi

[@codywatkins1759]

Awesome! Probably the first person on KZbin to do real world testing on a Cummins 6.7 before and after a CCV filter change. Bravo!

[@VERYMADMIKE]

When Dave blew into the meter, he was way over the limits of DWI (Dieseling While Influencing). Dave you Rock Brother‼️

[@DavesAutoCenterCenterville]

😂👍

[@Sunspot-19]

Best reply award goes to... VERYMADMIKE!!! 😆

[@iceman4531]

Thank you, Dave. I learn something new every time I watch your channel. I am a novice when it comes to cars. My trade is hvac/r. Your channel is one of three I look forward to watching daily. Thank your son for starting this channel.

[@DavesAutoCenterCenterville]

That is awesome!

[@BenKlassen1]

Great tool! If the cap's a dancin' it's no good.

[@bigmountain7561]

Diagnostics are just as important whether you client is a truck or a person. The more data you have the better you know what if anything is wrong. Great Videos Thank You 🙏

[@dirtydieselguy]

You and Gale Banks would be a hell of a combo

[@1FastKarNascar]

Gohdamn 2015 with close to 400K … and still runs good 👏🏾 bravo to that owner

[@Thultarn]

should go talk to the camper pullers before i quit in 21 i knew several with old dodges with over 1 million miles i parked 2 after 600k the 6.7 was running so good they couldnt diagnose why the fuel mileage was dropping. I had enough to do one of the 2 things that needed done but since it was still running so good they said ya have to change both the pump and injectors. changing one would kill the other and probably take out the engine.

[@gregwelch6658]

I have worked in the engine testing world for 20+ years and JTec flow meters have been used for blow by measurements in many applications. Super simple reliable product with excellent support if ever needed. Ziptie that meter under the hood and run the cable in the ca, check it out on a drive.

[@ceasarperez8567]

New Engine suck nowadays

[@anthonypeak2125]

The good old 6.4 powerstroke. Ticking time bomb.

[@gobluekurt]

I saw it and said I know what this thing is about to do! And it was even worse than expected. That good ole 6.4 never lets you down from being much worse than expected

[@robertrichards4236]

My career as an engineer continually taught me proof is always in the data. Collecting data then quantifying it to identify trends, making comparisons, and supporting arguments with statistical evidence is CONFIRMATION . . . . DONCHA LUVIT!

[@jseen9568]

Hey Dave, y'all basically did a FEV1 test in the beginning of the video. FEV1 stands for Forced expired volume in 1 second. It's a great test to assess lung function in COPD and other obstructive vs. restrictive lung diseases.

[@lgregg2478]

Well just in time for small airway disease? Not much in the way of Obstruction. lol

[@bikerevolutiontv]

That's a pretty cool test. I would like to see some scientific analysis to see if these numbers can come down. Maybe different oil or even rings

[@jennifermartin506]

Just tried Daves way to on my 2005 Ford. No issues. Learning so much.

[@trevorwhalley7466]

Well Dave, your new blowby toy tells us that the rings have failed, this is very vital info, as ANY missfire will cause oil contamination by fuel and carbon particles, with only a few thou clearance on journals etc, it becomes obvious why engines sieze or run their bearings. You and Lake Speed are highlighting the real seriousness of oils, but also the point that lots of factors also play into this situation.

[@thomasperina2990]

Hello Dave: This pressure transducer with the digital readout does a great job 👏 👍. TMP from N.J.

[@stevekupfer-j1z]

do a test on one of your new builds and compare

[@RonRussell-sj1zf]

Blow-by was always a parameter that we measured at Cummins Illinois/Cummins Northern Illinois as part of the dyno test. As I recall, It's been about 25 years or so, 3" H2O (might have been mercury) was the no go spec.

[@bearing_aficionado]

That Gorilla Ladder is a Godsend. A must-have for working on trucks or anything else

[@chuckatley1464]

not fair!! the cummins and the 6.4 powerstroke came with blowby from the factory! lol

[@anthonypeak2125]

I got 08 with 105 k and blowby is almost non existent. Maintenance, maintenance and also keeping the regens down.

[@rc2634]

This is amazing testing, bravo

[@DavesAutoCenterCenterville]

Thank you! Cheers!

[@Mustard-Squirrel]

Thanks for all your knowledge

[@Aceman597]

My 6.4l is still good at 180k . I checked it years ago when i bought it. Was a military truck.

[@anthonypeak2125]

Yah, military truck that is not regenerating. Problems are almost non existent on 6.4's. without emissions.

[@noro4185]

I would love to see the readings on a truck with a CCV that has been ran to the exhust pipe with venturi.

[@shawnwood9875]

Exactly.

[@Scubasteve22]

Hey Dave. Appreciate the info...Also one thing to consider on the used car inspection, at least in our area, dealers dont wanna fix or take money off for things that are wrong with vehicle....

[@DavesAutoCenterCenterville]

Yes, that can be true. At least you as the buyer would know what you are in for as far as probable repairs 👍

[@GMCOldsRichmond]

Love your channel.

[@helimech0]

I like to see you be methododical. That will give you the best information.

[@2491kridge]

“Maysure” 😂😂 always cracks me up lol

[@liftednation2094]

The 6.4 😂

[@Dieselman6.7]

I laughed so hard. Of course the 6.4 is bad 🤣

[@Menthos341]

6.4 just doing 6.4 things. Cracked pistons 😂

[@bigmurph1447]

Those 6.4 were made like that from the factory lol 😆

[@gobluekurt]

I saw it and said here we go!

[@therealmikebizzle3175]

Good stuff!

[@peted5217]

These are days of Roses for this shop. Monster repair invoices create yuge cash flo to keep well oiled shop humming.

[@leftyspinn]

You could use a pressure pulse sensor on the dipstick tube into a scope

[@ShaneGestson]

Awesome tool! Curious how it can be utilized to test gapless ring builds and the longevity of the rings sealing abilities. More data the better!

[@sheerwillsurvival2064]

Great video

[@DaveBigDawg]

High end monometer

[@Six_Actual]

Dig this!

[@jweaver7170]

More info to come !

[@lgregg2478]

This is interesting, I would like to know if there are standards with each model, and how they relate to rise of RPM.

[@krockz973]

Id love to see this on a "speedofair" piston motor.. make it happen dave thanks in advance!!

[@projectdirtbikes]

great video!

[@travhimself_]

Maybe I missed it, but where's my control? I'd be curious to see the numbers on a late-model low-mile truck.

[@justinremple7986]

Sweet

[@21psd]

Tyson, you know your boss thinks a lot of you when he's willing to trade spit with you!

[@stevekeenan9673]

Started as a breathalyzer 😂

[@TheHeadG4mer]

😂😂😂

[@taylorh3930]

My truck has watched me do the blow test time for it to do it 😂

[@rickjones6798]

That's an awesome little gadget I've been looking to buy a Duramax but so many of them in my price range they have 260,000 to 300 and some thousand miles on them love them guys say no blow by but I'd hate to end up buying one and have problems because they're so expensive 2 rebuild blossom video buddy keep them coming

[@NoName-c4y7h]

We have one at work with the Allison transmission, and I can't recall it ever needing anything at all with those miles. The only thing is 5k mile oil changes, and a battery replacement all its life.

[@rosslindsay7347]

Meter needs a max/ min flow reading hold function.

[@ar2043]

Nice!!!!

[@digger105337]

Breathalyzer for your engine.😂 My Grandfather used to homebuild mercury filled manometers back in the 60's to diagnose blow buy. He was a mad scientist for his time.

[@ModelTTime]

Great test. I'm wondering what causes the wear in these newer trucks. Is it possibly EGR? I have a 96 12 valve with 211000 miles and no blow by.

[@bigmurph1447]

I have a 96 12v to has 502000 miles little to no blowby

[@Bootchair]

Lack of oil changes. But yeah. If the engine has to chew on its own farts. Can’t be good for its longevity 😂

[@ericalford6799]

6.7 power stroke best engine on the market!!

[@Thultarn]

OMG peoples need to learn to take care of their trucks !!!!!!!!!!!!!!!!!!!! i pulled campers for years 04 5.9 cummins have almost 0 blow by cap sat like it was not running had 616k miles, 07 6.7 cummins was deleted when i got it, at 607k miles you would see just a puff of smoke come out the oil cap once every couple minutes... I got a 19 Ram that had a bad EGR from get go dealerships blew me off as i was complaining about low turbo pressure( they said normal brreak in had 14k when the problem started) at 74k miles it finally set the engine light on they charged me to clean the EGR, 2 days later i was broke down with the EGR stck wide open 10 days waiting for part in hotel and 3000 more dollars, after that it had blow by and used 2 quarts of oil every 5000 miles. after 10 more months of arguing truck had 170k on it i said come and get it... To me warrenty should have covered it because problem started at 14k and there is 4 dealerships that have records showing i had a complaint from the 14k to 20k but not one of them had any notes of why i was complaining...

[@Dave-yq9fh]

I'd be interested to see what it is on one of your brand new engines.

[@timothyengland3]

Always love watching your diagnostic stuff but this one showed the differences between known reasonable engines and that poor thing that couldnt warm up,,, wanna see what one of your speed of power engines does, after a break in period

[@carlformsma8075]

Dave you blew headgasket

[@joebaucom4537]

GREAT !

[@bradcallaghan8099]

You should call this the “15,000 mile oil change interval” test. I think we all can tell which truck owners didn’t fall for that “3-5k oil change “scam”.

[@deputytuttle3871]

You need a good security officer?? I'm in!!

[@KennethMyers-i2t]

It’s amazing you got that many trucks with that much blow by and most of all the manufactures don’t care whatsoever to improve the system and make it better where there’s no blow by no drag cars they do it and they take care of it on blow by an over 5000 hp but these trucks heremanufactures incompetency of the motor properly last 300,000 or 500,000 miles

[@Matt123a]

The EPA Act should be amended so that any politician that introduces more crippling standards on diesels shall be subjected to this blowhard test.

[@MtnTechie]

You didnt cut open any oil filters?

[@raydornbush]

I feel like this video is THE video I've been waiting for for a long *%$ time now, I don't know or remember if there is a similar video to this or not. What I do know is that I wondered about the true seriousness, for lack of a better word, about the blow by on my diesel truck in a more scientific approach with numbers to back up weather or not I should look into getting a rebuild done or wait.

[@brucekultgen132]

Does the PVC affect the outcome of the blow by?

[@MrBusy427]

My LB7 has a good bit when it’s hot but could care less runs perfect uses no oil

[@sethmichaelson6972]

Simple test. Cap bounces=bad cap doesn’t bounce=good

[@Arexodius]

Interesting test! Would you say that excessive blow by is a sure symptom of excessive ring wear? And if so, would that be primarily caused by a history of missed service intervals and/or the wrong oil chemistry?

[@sounboy4498]

You can hear a slight miss fire on the 6.4 lol

[@rsquared9703]

You and your blow by freaked me out. I have a 2012 TDI and check the cap, boy was it dancing and everything. Come to find out the vacuum pump is vented into the valve cover.

[@gulfy09]

Volkswagen route it to the intake.

[@rsquared9703]

@@gulfy09 maybe on some. I’m only familiar with my specific vehicle which is a diesel.

[@f.k.b.16]

2022 with 92,000 and sounds like that!? Who's putting antifreeze in their oil?

[@B.V.Luminous]

The block wall...😅

[@destinhook3826]

That was the 6.4 in the background

[@CarObsessed96]

The 22 with 92k was almost flawless and silent.

[@f.k.b.16]

@@CarObsessed96 Ahhh.... you're right! Crisis averted.

[@keonikelly3794]

so funny, my 2019 powerstroke with 86K miles just started to have blow-by. guess i'll be ordering an engine soon🤦🏽

[@justinremple7986]

I’d love for you to check my Volkswagen that has almost 400,000 miles!!! 😂😂

[@Crotch_Goblin1]

What VW?

[@MrBusy427]

My LB7 has a good bit when it’s hot but could are less runs perfect uses no oil

[@Quebecer_Powerstroke]

The 6.4 got a cracked piston !

[@justinmason713]

Wonder if any of them have a pcv reroute.

[@robertlandry8693]

The 6.4 has blow by when new. Keystone piston rings

[@FeX1411]

Should you not check the PVC system’s function first? To ensure its ventilation is to spec?

[@AdrianMcDaid]

Should this not been enabled on the video "My video contains paid promotion like a product placement, sponsorship, or endorsement" Interesting Video none the less.

[@andrewlindsay5075]

We done this 1998 to jaguar v8s to see did they need engines the tool came from jaguar

[@gulfrasta5844]

Looks like they are DUI with those blows.

[@morrow275]

Put that on one of your new motors

[@AlonzoJ-pf4dt]

Dave rule

[@tom-fc1zi]

Doesn't a clogged filter push any extra through the cap you have on? So replacing the crank breather filter let's more air through the filter and less through the test equipment. Meaning it's not reducing the blow by??

[@VMac822]

Exactly my thought. I think Dave is missing the boat on this a little bit? And a new crank case filter will do absolutely nothing for improved efficiency and power.

[@adotintheshark4848]

That first Duramax didn't need a test, it even sounded weak.

[@gregpaszt4671]

Dave if they hrs meters go by that a much more accurate measurement on engine run time hrs.

[@coveeclown9397]

whats the normal pressure supposed to be? for each vehicle and how much were they off?

[@captaintoyota3171]

See why weren't shops like this around when i was an ASE tech? Seriously the greedy low paying zero benefits work 12+hr day jobs where all you could get. Unless you took a independent "speed shop" job for peanuts hoping to soawn a career, but in midwest most of those are fly by night or drugs involved somehow. If Daves shop was where i worked i'd stayed a tech. Now im a commercial carpenter building biggest high rises,structures, and bridges. Making 3 times as much $$, fully paid benefits, a pension after 30yrs, and im healthier outside active. I mean ASE master techs should be making 50+dollars an hour 4 skill required. You must know mechanics and computer repair, code, hardeare software, ontop of complex engineering fixes. Yet you get paid less than most ppl who work at a bank, and are expected to have 1.5years of wages worth of personal tools. You can only move with a flatbed for 1000s of YOUR $$. No shop pays to move ur tools. I hope daves wages reflect ACTUAL cost of living. Most right wongers pay 15$ an hr think they r doing you a favor while making all the profit

[@MsFireboy2]

So Dave out of all the trucks which ones need require engine replacement?

[@gulfy09]

On older Volkswagen diesel they vent off oil vapours to the intake system between turbo and air filter// i don't know what these newer vehicles do.

[@jeremy2730Live]

I would have loved to see an old 7.3 powerstroke because i know that they love to throw smoke out of either, or both, the oil fill cap or the dipstick but have no pressure. I know from experience as I have one myself.

[@minnesotatomcat]

I’ve owned 5 different 7.3 powerstrokes with varying mileage and they would all fail the “making the oil cap bounce” test, but never had a problem with any of them. My 99 that I drive now has 265,000 miles on it and still going strong.

[@gulfy09]

Be good test to do a engine flush then new oil change.

[@CZ-kz7ug]

Every diesel owner trying to sell their truck will be running when they see you walking over with that blow by tool.

[@nickg7827]

Maaayzure ....I'm sayin it like that from now on

[@fully_retractable]

Are any of these trucks stock?

[@willyck948]

Just a thought, I'd imagine the pcv needs to be blocked off before testing🤔

[@infernoking7504]

I know theres blowby but also compression blowby for diesels

[@peckerpeter2078]

Shows these aren’t gonna make it to 200-300k or 500k miles. Those blow bye’s 💨 are gonna need tear downs/rebuilds new rings at min. Are these completely stock boost levels, or do some have upgrades like tuner devices with added boost levels? Are they towing commercial payloads/ cross country trips or they just personal occasional use vehicles. Surprised at how low the mileage was to have this type of problem?

[@thefatkid2963]

What would cause a crankcase case vacuum? I have already changed the pcv valve with no luck l.

[@DB52539]

damn Dave def makes a lot of guys happy blows as much as he does

[@DevilbyMoonlight]

there is always a small bit of blow by... but when the filler cap or the dip sticks is dancing in its holder its time for a rebuild....

[@Hobbyaddict-dh3di]

So is blow by always a motor that’s toast and needs replacing ?

[@Bootchair]

Yeah for the most part. turbocharged engines have blow by it’s just at what point is it worn rings, BHG, cracked piston, etc. also there is no sense in building just the bottom end. If you do the bottom end only, the top end is surely going to cause issues down the line. Imagine rebuilding the bottom end for the top end to only drop a valve and ruin that fresh built bottom end.

[@chrisgunsandguitars1403]

So when do you change a crank case filter as preventive maintenance?

[@andremclamb1310]

I believe with Cummins, it is at 75k miles