Extending life of aging timing chain

[KevinV]

The timing chain in my BMW 318i 1993 (300,000 miles) is beginning to show some age and makes a minor, mild rattling noise. Does any one have any suggestions on making the timeing chain last a bit longer (without doing the $800 timing chain change) ?

Someone suggested using a different oil (I used Maxlife 10W-40 in the summer).

Could the rattle be low oil pressure ?

Thanks for the help.

 

[Quest]

given the mileage/age of the engine, the timing chain already stretch and there's no way you can extend it's usefulness.

Besides: your chain tensioner would have been sufficiently worn anyways.

Get a new set of chain and chain tensioner, replace and enjoy.

No use fuzzing over worn chain...

Q.

 

[morris]

if you HAVE to keep it a while longer, keep the RPM down. when the chain wears through the cover youll have no way out.

 

[tinmanSC]

In general, no, there is no way to extend the life of a timing chain. Oil won't help, but it won't hurt either. At 300K the chain is likely stretched (there is no way to tighten it, other than the tensioner). Assuming that the noise you are hearing is in fact the timing chain, then the tensioner has probably reached its limit. Its been holding that chain for 300K miles, and it will be fully extended now (I assume it's self-adjusting?). No oil will help that, the chain and tensioner need to be replaced. If it has been loose for a long time, you'll also need to check the gears on the crank and cams. Sometimes they experience wear as the chain loosens. I do have some good news to give you... several 318i models have the ability to use later generation tensioners, which are better. You will have to do some hunting to find out if yours qualifies for the "upgrade."

 

[user52165]

How handy are you? A service manual, parts, and your own skill will enable this job at a great $$ savings.

 

[Chris142]

A loose timing chain needs to be replaced asap before it jumps and does major damage to The engine. can't prolong it's life if it's worn out.

 

[Cristobal]

I agree with Quest. Find a good mechanic rather than a stealership.

 

[MBS500]

try adding a can of LM MoS2, should be less friction...

 

[johnachak]

Let me get this straight, you have over 300,000 miles on a 19 year old car and you won't put in $800 to keep it running? Why not shop around for a mechanic who might do it a little cheaper?

 

[Donald]

The chain will break or damage timing chain cover if you wait. Waiting will only make it cost more. What happens if it goes? A tow, there goes $100. Is the engine an interference engine?
300K miles, you have gotten your monies worth for that chain.

 

[hattaresguy]

20w50 and keep the rpms down, no high rpm runs.

 

[default]

They tend to snap and take the rest of the engine with it once they start to rattle. You might as well be asking how to get more life out of a set of tires worn to the cords.

 

[meep]

Be Careful. If you swap a stretched chain, you need to swap the sprockets as well. The 318 does not use keyed cam sprockets, and the cam timing is set in the engine during assembly. It requires a $200 tool. If you are clever, and you get measurements of everything before disassembly, you can fake it during the install. But if you aren't willing to have to do it a 2nd time, this is not for the home mechanic.

BMW also uses a jig that guides the timing cover and valve cover into place as they all mate to the head. It is used to prevent the rubber gaskets from twisting/rolling during assembly. The one time I did this, I didn't have a jig, and it leaked after. It had to go to the dealer to get it seated right.

there are nylon chain guides on this engine. suspect yours are worn.

 

[mechtech2]

The guides and tensioner are very likely to be faulty as much as a worn chain.
Yes, the thicker oil can help with long term wear .
Timing chains chew up oil more tan belt equipped cars.
I would consider using Lubro Moly additive, also.

 

[artificialist]

Regular maintenance is the only thing that maximizes timing chain life. You could use Lucas oil additive to quiet it down, but it will not save the timing chain.

Also +1 on replacing the chain guides, sprockets, and all the other stuff related to the t-chain.

 

[antonmnster]

These engines are known for having weak tensioners.

It's possible that you can get away with throwing a tensioner in there and it will be just fine.

I had a 318is that had a noisy-as-heck timing chain but never had the chance to deal with it before a drunk driver killed the car. It was a wonderful car, and I miss it!

A tensioner is cheap and easy to instal. I'd start there.

 

[JHZR2]

The M42/M44 engines have known weak timing chain tensioners. It is a really easy replacement, its just a 19" bolt that is the cap and then the tensioner is right inside. Very simple.

Id also drop the oil pan and re-torque all the lower oil pan bolts, likely a few have backed out. They can really do a number when they wear through the oil pickup.

While you could have a sprocket issue, Id doubt it...

 

[dparm]

Originally Posted By: Quest
given the mileage/age of the engine, the timing chain already stretch and there's no way you can extend it's usefulness.

Besides: your chain tensioner would have been sufficiently worn anyways.

Get a new set of chain and chain tensioner, replace and enjoy.

No use fuzzing over worn chain...

Q.



Agreed. 300,000 miles without any maintenance is pretty awesome. Most timing belts need changing every 60-75k.

 

[gotib007]

Originally Posted By: JHZR2
It is a really easy replacement, its just a 19" bolt that is the cap and then the tensioner is right inside.


Wow, that's a big bolt!