Engine Rod Knock - Is It Worth To Be Fixed?

This is a visualization of what an engine rod knock is and what has to be replaced.
❗️If you find this video helpful, I would appreciate a $uper Thanks that can be found below the video.
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⁉️QUESTIONS
If you have any questions or I missed something, comment below and I’ll answer and try to help you out
If you find this video helpful, like it and subscribe to my new channel. I’ll have tons of videos on all kinds of car and truck repairs in the future.
#motorcarnut
⚠️Disclaimer:
The videos on Motorcarnut channel are posted with informational purpose only.
Information posted in this video does not guarantee any particular result. Use this information provided in the video with caution and at your own risk. It is the responsibility of the viewer to take this risk.
Motorcarnut is not responsible or liable for property damage, any loss damage, or injury related to or resulted from information posted in this video.

[@g0rdito]

Excellent video explaining engine knock in the big end. I've looked for a video for a long time and your video really explains everything I wanted to know the best! Thank you!

[@Motorcarnut]

Thank you very much! Appreciate the comment!

[@jonfitz8280]

The accent got me tapping in I'm learning more here than any where else

[@Motorcarnut]

Thank you! Really appreciated!

[@dr1380]

One of the best explanation I have watched regarding knocking engine, thank you for sharing your knowledge

[@Motorcarnut]

You are welcome! Thank you for the great feedback!

[@antonmare2870]

Video explains it in detail and cuts to the chase. Thank you for a very good video!!

[@Motorcarnut]

Glad you enjoyed it! Appreciate the comment

[@ugotaut3944]

An oil pressure gauge is very important because you'll notice low oil pressure time before you break the engine (normal use of the car). I think even that's why the old Benz are so reliable...

[@Motorcarnut]

Absolutely, I say that all the time. There are so many vehicles that have no oil gauge or even coolant gauges and also no oil dip sticks etc.

[@MyrtleBeachbigwheel]

Thanks you brotha , great info

[@Motorcarnut]

No problem 👍 Thank you for the feedback!

[@paullawrence8075]

Great information bro.

[@Motorcarnut]

Thanks for watching, appreciate the comment!

[@annikamerimaa7253]

Subscribed, ty for teaching us

[@Motorcarnut]

Thanks for the sub! You bet!

[@jessec4677]

Thanks for the video! I'm about to get into mine... Lost all the oil while driving and it seized.. Guess I gotta pull it apart and check the top and bottom end, hey? Not to mention find where the leak was and hope it isn't a cracked block... I'm just a weekend warrior... This'll be the biggest job I've done. 😵‍💫 So thanks for all the tips!! At least having KZbin and forums is way better than just the Haynes like back in the day, lol.

[@Motorcarnut]

That’s why we’re here! And good luck!

[@lindsayshelton5345]

Great conent keep it up brotha. From a fellow mechanic 💪

[@Motorcarnut]

Thank you bro, very much appreciated!

[@LuisC202]

This is The BEST video I found on this issue. Most videos show people sanding down the rod journal and reaplcing the bearing, but they don't tell you that it is a band-aid fix and doesn't last😂. This is the correct way to do the job. Buy a new crank , new bearings, and a new rod or rods .

[@nickhannum1195]

Super thanks! Keep it up buddy. Great video.

[@Motorcarnut]

Thank you too

[@kevinrbarker]

Thanks!

[@Motorcarnut]

Thank you very much for your support!

[@8307c4]

My experience with small engines (anything from 4hp single cylinder Briggs to 25hp V-Twin kawasaki) is that once internal issues such as these develop it is usually (probably 90% of the time) cheaper to replace the engine itself, unfortunately there's no way to know without taking the bad one apart but doing that also incurs labor hence cost. You want to save money, replace the engine itself boils it down to a specific figure, tearing the bad one apart involves variable costs that could very well run higher than just replacing it.

[@Motorcarnut]

Its different in automotive, but I find it's almost always cheaper to rebuild than replace. The more expensive the vehicle the more expensive the new engine will cost. Parts on the other hand don't rise as fast as well as the labor. Also depends if you're talking NEW or good used engines. Botton line for us at the shop is New is the most expensive followed by used then rebuilt which in turn is like new therefore the best and cheapest option for most customers.

[@vladimirtrump1068]

superthanks

[@nguyenconghoanyamaha3429]

Thank Pro ! I can call you a teacher You lesson Explain very clearly ! As I think the knock sound , might be due to the oil not supply , reason is neck somewhere ?😊

[@Motorcarnut]

Thank you for the comment! Appreciated! Yes lack of oil flow or low oil or low oil pressure are the reasons for engine knock

[@earl8590]

Just happened to my mx5 nc, bought the car for piss cheap as my first car and im taking it upon myself to fix it with 0 mechanical experience 😂 if im gona scrap it anyway i might aswell learn a few things

[@Everett901]

Great video. Man; are you anywhere close to Memphis TN? Im going through this right now.

[@Motorcarnut]

Thank you! Sorry, No NY as of now

[@Everett901]

@@Motorcarnut copy. I have a 2012 Shelby GT500 & not trying to get rid of it because of this problem. Started knocking 3 weeks ago.

[@Motorcarnut]

I wouldn’t either, worth fixing if it’s a clear car. Btw love Tennessee!!!

[@adamfranco4149]

Any way I can email a video of my old 46 caddy to see if it is in fact a rod knock? Trying to decipher the problem on my old car, great video and thanks for the info

[@Motorcarnut]

Just post on your channel and let me know

[@atomicdmt8763]

perhaps share insights on replacing bearings yourself.....engine in vehicle (if not too worn,damaged). Some very helpful videos on this using sandpaper and shoelace to polish

[@Motorcarnut]

Problem with that is it will never last and I don't recommend that type of repair. Because things have to be precisely measured and you have to ask yourself why did it happen in the first place?

[@alexiskomondorea8854]

What does it mean when someone says the “rod is spun”? I’m looking at buying a truck where this is the issue and trying to determine if it’s worth the price at the discount it’s being offered. Thanks for this visual! This was a great video!

[@Motorcarnut]

Thank you! It means the engine has to be rebuilt or replaced. Spun bearing is because engine suffered low or no engine oil so it’s a big job if you’re not mechanically inclined.

[@DavidHughMusing]

Great video Man! QUESTION for you- 1964 Olds 88 with a 394- it leaked bad when I bought it so I pulled the engine and replaced the gaskets- all the gaskets, except the heads. I was told the heads were done but the exhaust was so bad I didn't really drive the car, just towed it home and pulled the engine. Rebuilt the carb, the starter, new power steering pump.. everything. Back in the car now, it sounds great at start up but after maybe 10 minutes, it starts to knock. I suspected this might happen- so, can I do this myself, in my garage or do I need a machine shop? Can it be done without a machine shop? I know a guy- but he's expensive and really busy. What do you think? I'd value your feedback on this...

[@Motorcarnut]

Thank you! Appreciated. So since you know how to pull the engine I’d say yes! If it’s knocking changes are the crankshaft and at least one connecting rod will have to be replaced. Along with the rod and main bearings. Now depending on how much damage there is you may get lucky and the crankshaft is fine and can just be polished up ( I have a video on that) but no machine shop needed. You’re sure it’s a rod knock and not something in the valve train?

[@Hunspikey75]

Excellent video, but I kept wondering why do you keep on placing the rod on the wrong position on the crank, where it does not belong (to the center not moving part)?

[@Motorcarnut]

Thank you!, Yes, this video is explaining the rod knock noise and not a rebuild video.I was just showing how the noise is created and used the main journal on the crankshaft as an example.

[@Ninja4200ful]

What does the cost of this or piston slap issue in the subaru outback 2008 engines

[@Motorcarnut]

?

[@thedammchannel]

This guys definitely a Celtics fan lmao But good video n information thank you homie

[@Motorcarnut]

No problem!

[@newvilla8115]

Very well explained.

[@Motorcarnut]

Glad it was helpful! Thank you!

[@newvilla8115]

@@Motorcarnut can you replace the journal rod bearings without splitting the case? I am doing just a top end, cylinders and pistons: THANKS

[@Motorcarnut]

Depends on what type of engine. Some have two part oil pan and then a main bearing bridge that may block some of the journals. If you take the pan down and see all bearing journals then yes you can

[@user-lw7ld4id7q]

Look like it's frequently at same berings rod issues... any Ideal why this particular bering ?

[@Motorcarnut]

It does vary from 1 to 4. Oil bearing clearances are at 1000 of an inch so any disruption will cause a bearing to seize up. Mostly do to neglected oil changes or leaks not caught in time.

[@mihaibadone2677]

I have a problem on my Mercedes e220 cdi and the guy from grinding machine told me that the crankshaft is gone and it can’t be repaired Do you recommend to be replaced with genuine one or it’s ok with aftermarket one? Thanks

[@Motorcarnut]

That's a great question. It depends on a couple of things, like is the car worth the extra money? is the cost between the OEM and aftermarket that much difference in price? Etc. If you really want to keep the car i'd go for orig. part however you can try to find online a remanufactured OEM crank or a used OEM good one on ebay and still save some money.

[@tonyluna3302]

Just happened on my infinity vr30ddtt redsport it’s at the dealer right now and I have warranty so hopefully since all my levels (coolant and oil) were topped off and maintenance records are good that I won’t be put at fault for the knock….. I have coolant coming out of my exhaust, milky oil cap… bad head gasket is the suspect of the knocking I’m assuming? Any other thoughts

[@Motorcarnut]

Sounds right to me. Diluted oil blew the rod bearings

[@elshammamcneal3772]

So did they accept responsibility for the knock sound

[@kevinrbarker]

Great! I just did my bearings, metal in the oil, found a spun bearing, but still have the knock. What gives carnutguy?

[@Motorcarnut]

You can’t just replace the bearings, the crankshaft journals and connecting rods have to be measured and or replaced if out of spec or scored.

[@jacobgariepy4258]

I have a lower bearing failure on my 2015 Subaru wrx. My Mechanic quoted me 8,200, does that sounds reasonable because that sounded high to me?

[@Motorcarnut]

You can buy a brand new engine for that price. Shop around. $4000 max depending whats damaged.

[@mabuelaadam5837]

I did experience the cranking sound in my engine Fiat Palio 1.2 and suddenly the car stops itself and after some few minutes I tried to start again and the sound was heavy so I opened the sump found metals like mud in the tray so can I fixed it without taking out head cylinder?

[@Motorcarnut]

Not the proper way ,no

[@williamfuller496]

I have a 2007 Chevy Trailblazer, IL6 with knocking, sounds like a rod but maybe its the bearing, it was low on oil and started knocking

[@Motorcarnut]

Running low on oil is usually is never a good outcome

[@zakza154]

Can you give me estimation the price for fixed engine wv Routan 2010 I have Siemens problem

[@Motorcarnut]

If can range dramatically on exactly what’s wrong with the engine, if you will put a used one in or rebuild the one you have. Either way can cost a couple thousand dollars easy.

[@SilvorAltAccount]

I swear to god that bostonian accent gives me such vibes. It's like playing max payne or something and just listening to one of the gangsters explaining to his buddy, in detail, how a car engine works and why his ride is irreversably screwed lmao All joking aside though, this vid and your channel in general is great and informative but I just had to mention the accent

[@Motorcarnut]

Thank You! Actually i'm not from Boston, lol

[@tanweerahmed6861]

hi can we have knock due to piston slap and are bearing failure and piston slap related to each other ? thanks

[@Motorcarnut]

No bearing rod knock is not the same or related to piston slap. However both can be caused by oil starvation.

[@tanweerahmed6861]

@@Motorcarnut ​I have my car at dealership for warranty claim but they are refusing to replace engine claiming the noise is because of piston wear and not due to bearing wear knock , they use some type of tool to test it without opening engine and when I ask them that sound just started to come as soon as I get check engine light and there was no oil leak/burning before that they cant explain that and sys that we can see that cylinder walls are scraped , its a kia soul with engines under extended warranty due to rod bearing wear

[@tanweerahmed6861]

@@Motorcarnut its getting code P1326 but they are refusing to accept its due to bearing wear without opening engine and physically inspect it

[@Motorcarnut]

If they did not find your oil level low, they must fix it as it is directly caused by oil starvation especially with the code P1326. That tool they used was a bore scope. Go to another dealership if possible or threaten to sue.

[@tanweerahmed6861]

@@Motorcarnut oil level was perfectly correct and car was not burning/leaking any oil , I confirm it before last 2 oil changes that oil level was ok before oil change (so no burning or leaking), there is already a class action law suite against them in Canada due to this issue but they are shamelessly not resolving it and lingering on, secondly refusal of engine change is coming from kia corporate as the service manger on kia dealership even show me their email showing that he requested a goodwill replacement of engine which they also deny , do you think taking it to another dealership can change bearing clearance test results or this this a good idea to talk to original dealership where this car was service throughout , the issue is that dealership is around 500KM from where i am currently living

[@christyhorner9811]

If this has happened is it considered a blown engine? Can the vehicle be driven after this happens?

[@Motorcarnut]

No it can’t be driven and yes it is considered blown but can be rebuilt or replaced.

[@muhammadtai4972]

Hi, would you recommend using 10w40 or stay with 5w30 engine oil after rebuilding an engine which suffered a bearing knock? Which one would be best to use to make sure we don't suffer a bearing knock in future. 10w40 is a bit thicker than 5w30. Thanks

[@Motorcarnut]

You can use the 10w40 with no issues

[@muhammadtai4972]

​@@MotorcarnutThanks for the quick response. Will use 10w40

[@shottaafrif4213]

My car in like stops after 3rd gear. Is that bad?

[@Motorcarnut]

Yes, have to take to local mechanic

[@muhammadtai4972]

Hi, Mechanic opened up the entire engine and found the ONE Rod cap was fitted upside down which damaged that one conrod groove and the one big end bearing that went on that conrod. He said in order to fix up that knocking noise, we must get: ●1 conrod ●Polish crankshaft (crankshaft was not damaged) ●Change all big end bearings since it comes in a set when bought. (My argument was why change all big end bearings when just the one bearing was damaged because of the upside down rod CAP? What's the need to polish crankshaft if it wasn't damaged? Or it's fine if the engineer polishes it? I'm just worried why polish, what if it weakens the crankshaft. Thanks Is he right to change all the bearings?

[@muhammadtai4972]

His going to put the same standard size bearings because his not cutting the crank (only polishing crank) no need for undersized bearings. Is he correct?

[@Motorcarnut]

If metal filings were not circulated in the engine and scored the other bearings then just replace that rod and rod bearings for that cylinder and just polish that one journal. If you’re on a budget. No polishing the crank will not weaken it. The way he wants to do it is the proper way but will cost more money and I would do it that way as well. But as stated, if your tight for money the other way will work.

[@muhammadtai4972]

Thanks. I am on a tight budget but the guy explained to me that he doesn't want to open up the engine again, he promised that if he fixes it his way now then i will not have issues again. BEARINGS come in a set so even if i change bearings for one rod i will still have to pay for the entire set of bearings when bought, hope you understand what im saying. Really disappointed that they don't sell lose rod bearings for one cylinder. Have to buy for all cylinders. I can find a lose rod? Don't want to buy 4 rods otherwise ill be in big debt. Struggling to find parts though for L15z engine. Only the honda dealer has got stock in south Africa. Dealers are very pricey.

[@user-lw7ld4id7q]

Bying parts directly from BMW is expensive, where other place can we buy BMW engine parts ? Specifically this BMW N20 engine ?

[@Motorcarnut]

You can fine them online.

[@connectlogic]

yep this just happened to my car ..scrapping it for 300 bucks

[@Motorcarnut]

Sorry to hear that.

[@nicodaniels130]

Same thing I just bought it and put a bunch of money in it such a shame

[@RookitMaster]

​@@nicodaniels130 if you jack your car up and drian the oil out and remove the oil pan under the engine some cars you can access the pistons rods and the crank shaft right there and you can change them out from underneath with out removing the whole engine that is if its just the rod bearings, if there is piston problem or or a piston rod problem then yeah you might have to take the engine out, but then again some cars you can get away with removing just the engine head and accessing tbe pistons and rods while its the rest of the engine is still mounted in your vehicle

[@stanky_yt2251]

Oh yeah, same deal here, but I got mine for $500

[@mohammedrubian]

Loser

[@waynehick]

Just happened to mine. Would you recommend rebuilding or buying a used one. Rebuiding is cheaper but concerns that metal fragments would have damaged the rest of the engine.

[@Motorcarnut]

If the engine ran fine before I would rebuild what you have and clean up any metal or replace oil pump too.

[@waynehick]

@Motorcarnut I bought it a week ago and the engine started knocking. Metal found in the oil filter. Basically got scammed. Don't really know the history of the engine. Still think rebuild or used engine? Thanks mate

[@Motorcarnut]

@waynehick I would but maybe you’re better off if you find one that you can hear running then buy that one a put it in yours.

[@GVGR11B]

Start by removing the girdle and pulling caps off. Replacing bearings is the simplest way to fix it. However, that metal on metal contact, depending on how bad the bearing is, can scar and scratch the crank. If the crank is scarred too much then you'll need a new crank otherwise it'll just end up getting rod knock again sooner rather than later

[@leroydavids2972]

I had engine knock did everything you said in the video even replace starter and diesel fuel filter we struggled starting the bakkie and the engine knock again and damaged the bearing what was the reason

[@user-zn3hn5be1v]

Also would be cheaper to relace the entire egine and faster than replacing the Crank, etc.

[@Motorcarnut]

It's not cheaper if you did it yourself. But, yes faster.

[@user-zn3hn5be1v]

Assuming a used engine much cheaper @@Motorcarnut

[@Shawn_mccallister]

So there’s no way to fix this? My car started doing this a couple days ago and idk what to do, I’m still in school and work part time so I don’t make much. But I don’t have a way to get to work or school now

[@Shawn_mccallister]

It first started the other day after I went over some speed bumps. I’m so stressed about this

[@Motorcarnut]

Are you sure it’s an engine knock? Going over some bumps won’t do that?

[@curtthechameleon]

Yep. Mine just started knocking yesterday. Sucks. New vehicle time. Engine has 175000 on it.

[@Motorcarnut]

Sorry to hear that.

[@RookitMaster]

My crankshaf can turn by hand easily at a steady pace, but it will get harder to turn when it rotates to a certain point but when that hard point is passed it get easy again until it comes back around to that spot, Oh and all the pistons and rods are all put together and attached, but why is it doing this?

[@Motorcarnut]

It’s normal, you’re feeling the compression when turning it over

[@RookitMaster]

@@Motorcarnut oh okay thanks, just wanted to be sure it wasn't anything bad

[@Motorcarnut]

@RookitMaster no problem!

[@Formula1-Dave]

"Thin film of oil" "viscosity" that's how i know you're a great mechanic/engineer ❤

[@Motorcarnut]

Thank you! Really appreciate the your feedback!

[@Ichibantsuki]

Fuck I think this just happened to my car hahaha nice new year gift for me

[@Motorcarnut]

Sorry to hear that

[@DeathSpirit9]

Same thing happened to my 370z yesterday smh

[@knight-ot3ji]

Same happened to me Sunday

[@user-zn3hn5be1v]

Even doing this DYI if the vehicle is not worth at least $20k+ the cost of the parts can easily exceed the value of the vehicle and nOT pay todo i. Trade it in for a a better running pre-owned vehicle.

[@Motorcarnut]

Well many factors come into play here. If I am doing my own vehicle, I'd definitely rebuild it then I have a new engine that's more reliable then someones pre owned vehicle and way cheaper and more reliable.

[@sirdickson]

❤

[@Motorcarnut]

Thank you

[@ov7960]

👍

[@Motorcarnut]

Thank you!

[@muhammadtai4972]

Are rod bearings easy to replace? Mechanic cannot make a mistake when replacing rod bearings?

[@Motorcarnut]

Most of the times the engine has to come out of the vehicle to replace them and usually it destroys the crank journals too so it's a big job and absolutely a mechanic can make mistakes and not measure oil bearing clearances etc.properly.

[@muhammadtai4972]

@@Motorcarnut what do you mean by oil bearing clearance mistake

[@Motorcarnut]

@muhammadtai4972 oil bearing clearances have to be checked for proper clearance, if too big or too small will cause crankshaft damage

[@muhammadtai4972]

@@Motorcarnut Even if the mechanic is putting new standard size rod bearings? Im pretty sure the mechanic knows about this things....im just stressing too much for nothing

[@Motorcarnut]

@muhammadtai4972 you probably are

[@Akak-bi2zx]

My car was waterlogged. This happened?

[@Motorcarnut]

Hydro locked probably

[@Akak-bi2zx]

White smoke and engine shaking ..noise from engine

[@Motorcarnut]

Engine knock then

[@Akak-bi2zx]

Yes ..knock sound from engine

[@bryantsculpting42]

replenish your working surface particle board is a terrible choice.

[@Motorcarnut]

You’re so right, it’s one of many. I usually just take photos and videos on this one.

[@gsgcarreviews]

That has to be an n54 lol

[@Motorcarnut]

Close, N20

[@Sam_Molina]

Usually....people send their car to the junkyard.... sad face

[@Motorcarnut]

I’m trying to help people avoid that.

[@cdeprima1209]

You guys use too light of engine oil duh! :(

[@Motorcarnut]

That's not the issue

[@cdeprima1209]

That is the issue, that causes the problems duh!

[@Motorcarnut]

THIS IS kzbin.info/www/bejne/iHKvhWiJeNqHec0

[@southernman523]

Why not refer to the rod bearings as rod rings. Piston ring,rod ring . calling them bearings is confusing 😦

[@Motorcarnut]

Because they are called rod bearings just like main bearings. Pistons have rings not bearings.

[@jessec4677]

Bearings help things slide against each other with less friction.. Piston rings are to seal it and keep all the expanding gas inside the cylinder.. So rod bearings are bearings, but piston rings are not..