m30 timing chain tensioner/guide rails

[eugeman]

-How reliable are these, do they usually last the life of the engine?

-Do they give any indication when they are on their way out?

TIA!

[E30SPDFRK]

Technically they should last the life of the engine, but mine were really worn after 230k.

There would be a rattling noise coming from the front of the engine if they are going bad.


Replace them while the engine is out of the car. It will be the easiest time to do it and it is good preventative maintenance.

[learningcurve86]

not that i think i need to do this as my engine has 120k kilometers... but how much were they?

[E30SPDFRK]

I have no idea, it was a while ago. Under $100 I believe.

edit: under $80 from BAV

[Jean]

Cheap, compared to the M rails lol

[yert315]

I got mine for pretty cheap. I bought a timing cover gasket set, rear main seal, oil chain tensioner, timing chain tensioner, timing chain guide rail, and front crank seal (goes on the outside of the timing cover) for $105.

I suggest you buy all of that^^

[eugeman]

Is there an updated tensioner (like the M42)?

[euroshark]

Cheap, compared to the M rails lol

Indeed. One of the few reasons I didn't jump on the very reasonably priced, but semi high mileage, M635 that I found a while back.

[BoostMW]

My 2 cents is "I would replace them and every other gasket, I found after I installed my b35 there was a noise in front and pulled front covers off and found them broken, for couple hundred bucks you will save your sellf a huge head ache later with leaking gaskets and such, plus you can pull the oil pan of and get the sludge out of it."etc

[eugeman]

I got mine for pretty cheap. I bought a timing cover gasket set, rear main seal, oil chain tensioner, timing chain tensioner, timing chain guide rail, and front crank seal (goes on the outside of the timing cover) for $105.

I suggest you buy all of that^^

not replacing the timing chain while you are in there?

[yert315]

timing chain was fine and should last the life of the engine anyway. I suppose it wouldn't hurt to replace it, but isn't necessary

[E30SPDFRK]

If the tensioners are worn, the chain has probably stretched a bit. If you're changing one, change the other.

[RickSloan]

the only way the tensioner go is if you seize the cam... the guide rail doesnt last long when you do that....

replace it tho if you have things torn down and out of the car. When i picked some up they were $70 total for both the tensioner and the rail

good luck with the crank bolt

[E30SPDFRK]

Yeah, I meant the guide rails, not the tensioner.

[RickSloan]

i actually meant just the guide rail as well... the tensioner actually seemed to survive the incident...