(Impending) Knock

[Fordlover96]

Hey guys, I have a question. (And yes I know I do ask a lot of questions on this forum and don't really give much information back, but that's what happens when your a Newbie! Haha.) I've have been looking around this forum in search of information on this engine's infamous knock. (I still don't understand if it is the main bearings or rod bearings....or if those are the same thing! Haha). And because my car is getting closer to the 100k mark I have been looking into it, however when my car does get to that point i do plan on have the 60k valve lash done and possibly the bearings. What Mileage does it begin at? Is it all of a sudden or happen slowly over a period of time? Does the crank have to machined after it and oversized bearings put in? Any information would be A GREAT HELP. I'm just trying to gather as much research as I can.

P.S, the car was never driven hard. Even by me, as a teenager!Haha. Oh and Happy New Years Everyone!!!

 

[rubydist]

normally, if you are paying attention and know what it sounds like, you can hear it as the rod bearings get sloppy.

however, given your 'newbie-ness' and the questions you have asked, I would not count on that.

if your car is a mtx, you should plan to replace the rod bearings. if it is an atx, you should have plenty of time before that needs to be done. if you do this before a bearing failure (i.e. spun bearing) occurs, you just replace them with standard size bearings and you do not need to turn the crank.

btw, the main bearings are the ones that the crank turns on in the block. the rod bearings are the ones where the rods attach to the crank.

 

[Fordlover96]

Wow. Thank you so much for the information. And my car is an ATX, so ill probably just have them changed the next time it goes in for a major job. And yes, my "newbie-ness" does hold me back. Haha. I really do appreciate the info. Happy New years to ya!

 

[jimtash]

I recently pulled apart a 180K mile 3.2L ATX engine. The bearings were in good condition for the mileage and still had plenty of wear left. Oil pan had the original Yamaha sealant on it so it's doubtful that they ever were replaced.

 

[msteiny]

Doing the bearings is more of a preventative maintenance item. Since Yamaha used crappy bearings when the engine was origanally put together. If you would like to look at more info I have put a couple of links down. Its not hard to change the bearings just time consuming, and you will want to take your time. Having them done elsewere can be kind of expensive.

http://www.kurtmetros.com/bearings.html
http://www.shophoenixproject.com/rodbearings/rodbearings.htm

 

[Fordlover96]

Thanks guys. Im sure im just overly worried about it, since my car is only at 70k. And ill be sure to check out those links!! Thanks!

 

[Dinosauro]

Rod Bearings

Hi Guys -

Given that replacement rod bearings are getting pretty close to unobtanium, and given that the top half of bearings wears first and more, would it be wise to start collecting used bottom-halves to keep our cars going ?

Dinosauro

 

[sperold]

Sure, start saving them if you have a source.
Every now and then, a batch shows up for sale on places like RockAuto. I think they are newly manufactured rather than dusty old stock, so just keep an eye out.
I have never had rod bearing issues, even on standard transmission cars, with up to a quarter of a million miles. But I am not turning 7000 rpm on a daily basis.
If you demand top performance, you will need the new bearings. If you are using your car in a regular manner, with a spurt of performance every now and then, the car may outlast you, as it is.

 

[jimtash]

What do you mean they are getting hard to find? They're on RockAuto right now. It's the mains that are obsolete.

 

[rubydist]

standard size rod bearings were out of stock for a month or two in the middle of last year.

apparently more were made, but the price has jumped about 50% (since they were now made in a lot smaller batch than the first time is the common thought.)

 

[jimtash]

They were $10.00 on RockAuto last month. Now they're back down to $8.00 and some change.