Time to change Timing belt?

I don't get it. Why would you replace it at only half of its rated life ?

Besides, if your 97 Legacy OB is anything like mine, the front cam and/or crank seals will start leaking like crazy pretty soon, and you can have them and the timing belt done in one fell swoop when that happens.

John

John,

I guess that I have the impression that timing belts are generally considered to last for 60K. I've read somewhere that the only car that has a 100K timing belt is a new Honda model, and that's a timing "chain" rather than a timing "belt".

There was a typo in my original post, and current mileage is 98K, so assuming the 60K life, and the change at 48K, the current belt has 50K miles on it, so I'm wondering if it's time to change it before it breaks...

As far as I know, they were originally rated to last at least 60k miles on the 2.

2l and 80k miles on the 2.5l engine (which probably is what you have).

Those specs are based on the fact that, except for manufacturing defects, failures due to wear begin to occur above this rated mileage. In theory, swapping the belts too often simply increases your chances of installing a faulty belt which is likely to snap BEFORE reaching the end of its rated life.

OTOH I am pretty sure that there are 200k mile subarus out there running on the original timing belts.

The belt itself is not THAT cheap ($60 - $80 in the US) but the bulk of the expense of a change is labor. That's why many recommend replacing the cam shaft seals, water pump and sometimes the belt tensioner while the timing belt covers are off for a belt change.

Timing chains don't usually get replaced in regular intervals - the recommendation by Honda may refer to service intervals.

florian

You've been misinformed. As far as I know, chains have NO rated life. They typically never cause a problem but there are exceptions. Many belts have a longer life than what you have been accustomed to, apparently, and not just with Honda. (By the way, the Honda model you refer to is not a chain, I'm fairly certain.) I can't say what the specs call for on your engine, but the manual should be easy enough to come by. Your original dealership saw an opportunity to sell a belt much before it was due, I bet, and you went along with it. It is common that they use the REVERSE sales technique, suggesting a change in waterpump when you do the suggested timing belt change. It's a wise decision to go with that suggestion, I think. You just got yours done a little early the first time, but that is no reason to keep on undershooting the limit by that much. I expect to have the belts and waterpumps changed on our 99 Foresters in the 90K miles range, a little ahead of schedule.

You ought to check your owners manual for the recommended interval. My '99 Outback Legacy manual says 105k miles. I changed it at 83k because everything was apart. The belt looked brand new. I can't recall *anyone* on the group claiming a timing belt only failure from age.

D H,

I may not have been clear in my earlier post. When they changed the belt earlier, they did it under warranty (no charge to me)...

If it breaks it can destroy your engine. Replace it. Its reaching the end of its servicable life.

Rob

Yep. I know that. That's why the original post :)....

BTW, now I'm really confused. So far:

1) Someone said belts are rated 105K miles 2) Someone else (linked page) said 60K miles 3) Someone else said don't change it just because of rating

Plus :(,. now that I'm researching this, I checked that last repair, and noted that part of what they did was the separator plate and valve cover gaskets, and I think that I probably should've had them replace the timing belt since they had to pull the engine anyway :(!!!

Darn!!!

That was me. It's in my '99 legacy outback manual. What's yours say?

More importantly the listing indicates if the engine is an interference> design. Note that all of the Subaru's are of the crash proof design. Of> course nothing was better for life than the old Subaru's that had gears> instead of belts or chains.>

Thanks for the link to that nice document. However, something seems amiss to me here with none of the Subaru engines being marked with an asterisk to denote interference engine. I thought that some of these are, but maybe there was some other caution that folks referred to which was not technically "interference" but still could be bad news for engine parts. Can anyone else shed some light on this? Or am I just befuddled here?

"Rob Duncan" wrote in news: snipped-for-privacy@gbronline.com:

This is hogwash. The 2.5 motor is a non-interference engine. The worst that will happen is that you'll be stranded somewhere and need a tow. Replace your timing belt at its recommended interval, which should be stated in your maintenance manual.

-S.S-

I still think you're worrying yourself unnecessarily. I would not be changing a belt at 50K miles unless there were some reason to think it was malfunctioning or had otherwise been unduly stressed or showing signs of visible wear. Probably none of these applies?

Jim,

Hmm. Interesting.

Ours is a '97 Outback Legacy, with 2.5L engine.

I'm assuming "camshaft drive belt" is the same as "timing belt"...

For the 2.5L engine, according to both the maintenance booklet, and the Subaru website, they recommend inspection at 30K, 60K, and 90K, with replacement at 105K.

For the 1.8L, 2.2L, and 3.3L engine, they recommend inspection at 30K, with replacement at 60K.

So, I have a couple of more questions:

1) Along the lines of what someone else has posted in this thread, is the 2.5L a "non-interference" or "interference" engine?

2) Going back to my original post, and going through our service receipts, they replaced the timing belt at about 44.5K under warranty. Now that I'm going through all of this, I recall the situation. We had the water pump start leaking at that time and took it in to the dealer. They came back and said they'd be repairing the water pump under warranty, and they suggested (really) replacing the timing belt (again, under warranty), which I agreed to. So, given the recommended inspection/replacement intervals (and again, going back to my original post), do we start the 30K/60K/90K inspection with

105K replacement cycle from the 44.5K mile point? In other words, should we have gotten it inspected at ~75K, 105K, 135K, with recommended replacement at 150K?

3) BTW, as mentioned earlier, I thought our last repair (in January) was for gaskets. This was out-of-warranty. But I just checked our records, and I found that it was for a valve cover gasket and a "separator plate". What's strange is that in going through our service records just now, I found that they had replaced the separator plate in early 2001 also (sorry, I forgot). Is this separator plate something that is going to keep giving us a problem (every 2-3 years)??

Skared,

I'm guessing (hoping, really :)) that you're right. As I just posted, the

2.5L is indicated for timing belt replacement at 105K mile intervals (vs. 60K for the 1.8L, 2.2L, and 3.3L), so that kind of leads me to thinking that the 2.5L is "non-interference"?

Although there is still some confusion, this issue has been covered extensively on the bds. at

do a search there.(probably the best forum for repair, maintanece questions - and are good too). It is clear that MOST Subaru engines of newer design (EJ and up?) can theoretically have valve-to-valve collisions if the TB breaks. Probably most likely at higher RPMS, can also be troublesome when the engine is being assembled/worked on sitting on the bench. ALL the DOHC engines seem to be on this list. A poster from maintains that some later (higher compression?) 2.2l SOHC engines can experience piston-valve interference.

There are also documented inspection guidelines for TB. If your car's manual says 105k miles and you're concerned, have an experience mech examine the teeth/belt condition at whatever point you wish. Personally, haveing experienced unexpected early catastrophic TB failure on a Honda and a Toyota, I would be conservative about changing not just the belt but evrything that touces it that has a bearing(except crank/cams of course - and they get new seals) UNLESS I WAS POSITIVE BEYOND DOUBT that my exact engine was COMPLETELY non-interference in ALL respects. Even then, it's going to be very inconvenient to be broke down out of town, on the freeway or have to go rescue a daughter at night somewhere. Not much consolation, seems to me, for getting that last 150-500-whatever miles of use outta a car part. Do you drive on your tires until one of them blows out? If you don't want to inspect and change TBs - stay with the ones driven by chains/gears.

Carl

1 Lucky Texan

D H wrote:

What model Toyota engine was that? I was aware that all Honda engines will crash but I'm very surprised to here that your Toyota was also damaged. According to an old listing I had there were only two engines types using belts that Toyota made of the interference type. One was the Diesel and the other was the 1.5L used on the Tercel model for a couple of years.