Oil leak cause premature timing belt failure?

[Zack]

I have a '90 Legacy AWD Auto Wagon with about 168,000 miles on it. A year (and 2000 miles) ago, I had an independent mechanic who was very highly recommended by several Subaru-owning friends replace the (original) struts and oilpan. When I picked up the car, the mechanic mentioned that some oil was leaking from the seals at the front of the engine. His concern was that the leaking oil would get onto the timing belt and cause premature timing belt failure, and he recommended that the seals be replaced (and of course a new timing belt and water pump be installed while the engine was stripped down). Since I use the car very lightly (it has a non-interference engine) he didn't think I had to do this immediately, but said I should consider it before taking a long trip.

 

I'm now about to take the car on a vacation that will probably involve around 1,700 miles of driving. Can anyone give me any further advice about the likelihood of leaking oil leading to timing belt failure? The belt was last replaced ten years ago at 117,000 miles (the work was done by a previous owner at a dealer whose service department doesn't have the greatest reputation).

 

Having put significant money into the car last year for struts, oilpan, and 130,000 service, I was really hoping to wait another year before doing another major service. On the other hand, I don't want to run the risk of ruining a vacation by having an engine failure in the middle of it! The car is otherwise in great mechanical condition and has been extremely reliable. Any advice appreciated!

Thanks,

Zack

[hohieu]

Well, it sounds like very good advice. It is possible that oil could contaminate the belt and cause it skip. Oil will also deteriorate your already old belt. It will probably be ok for your trip, but you'd probably enjoy your vacation much more without the odd chance that it does indeed fail.

 

You have to raise the engine to replace the oil pan on my Phase II 2.5 engine, and I imagine it's the same for your 2.2. I suppose he could pull the engine entirely to make the timing belt job a bit easier. How much would you save in labor charges if you were to have it done now?

 

The t-belt interval on your car is 60K miles, though a decent quality belt can go at least 10years/100K, and the water pump should comfortably do about the same (other will chime in on this point.) If it snaps, the worst that will happen is you'll need to have the car towed -- as mentioned by your mechanic, you have a non-interference engine

 

If you have the funds, it would be a good idea to go ahead and do it for your trip, especially if you're planning on keeping this car for as long as possible. Subaru now uses the new viton crank and cam seals, which should hold up for as long as you own this car.

 

If you go ahead with the work, also ask him to check tensioner and idlers -- particularly the cogged idler, which bears the highest load and, therefore, seems to be the first to go -- and to reseal the oil pump.

 

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[four-fleet-feet]

I'd change the belt before you leave, you're overdue. However, you'd also have to fix the oil leaks at the same time, or it's for naught.

 

Can't spring for it now? Make sure you get a timing belt and carry it with you, as well as the instructions for replacing it. From the mileage you stated, I'm guessing you might go into non-Subaru areas. If you end up with Joe Blow to throw on a belt to get you home, he probably won't have a clue how to do it.

 

Also throwing on the belt to get you home, if the leaks aren't fixed, can just ruin it as well.

 

(Dragon used to have a 'you're on fire' oil leak, before we did her t-belt service - I know this one well!)

[idosubaru]

You need to replace the belt, it's 10 years old

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And since I had this happen last year...i'll elaborate:

Oil on the belt causes timing belt failures.

Oil leaks do not.

 

see the difference? just because oil is leaking or seaping doesn't mean it's getting onto the timing belt. oil seaping out the seals is very common on older subaru's. usually they leak very slowly and don't actually get on the timing belt.

 

but...i installed a new timing belt on a friends car last year. the crank seal was leaking enough to actually get on the timing belt (it was leaking A LOT!). the brand new belt lasted less than 10,000 miles and only a couple months. you can even find my thread about it on this forum. it's titled something like "can oil cause timing belt failure" or something like that. and the overwhelming consensus, as well as my experience, is most definitely.

 

Your belt is over due for a change anyway. Forget mileage, your belt is 10 years old, it needs replaced if you want a reliable vehicle. Of course you might make 2,000 more miles just fine, but i wouldn't be surprised if you didn't either.

 

Also - your engine having 170,000 miles on it generally necessitates a full timing belt job - including all the pulleys and tensioner as well. if you don't do those now you're hoping the originals make it to 230,000 miles for the next timing belt change. that's too many miles to reliably expect out of a set of 20 year old pulleys, i can guarantee at least one (and probably more) are low on grease and noisey. actually...most even with only 100,000 and late 90's that i do need at least one pulley replaced - usually the toothed idler pulley seems to loose grease the fastest. or you can regrease or replace the bearings, but that's rather intensive for most people/mechanics to do. much easier to just replace.

 

I go to ebay for these, you can buy an entire timing kit including the belt and all the idlers and tensioner for a reasonable price. Getting them all from subaru is cost prohibitive as they are very expensive.

 

If you don't do it before your trip i'd plan on doing it before next summer. You've got a great engine that easily has a few more years in it, no point in having known maintenance issues strand you now.

[Zack]

Thank you everyone for the responses! The answer seems clear, and I've gone ahead and scheduled the work. Incidentally, the mechanic had already speced replacement pulleys and tensioner as part of his estimate. Thanks again for the help!

[OB99W]

Ask your mechanic to check that the oil pump back plate screws are tight -- if loose, that can cause leaks at the crank seal.

 

By the way, check that the PCV system is working correctly, since if plugged it can cause or worsen leaks at all the seals.