M20 Timing Belt Lasting 90,000 Miles?

[Gary Yogurt]

So...I'm traveling a ways tomorrow to take a look at 325i convertible that looks great but the owner of 8+ years says he has not changed the timing belt and does not know when it was done last. He says he bought the car with a little over 50,000 miles on it. The odometer now reads almost 140,000.

Is there any way that this is possible? That's 90,000 miles. On a piece of reinforced rubber.

Is that even theoretically possible?!

He's not one to let a mechanic do the maintenance, so unless he's senile and completely forgot, I have to assume he's telling the truth.

Compete insanity? I obviously wouldn't even turn the key of the car if I bought it.

[Gary Yogurt]

A bit of an update, I ran a VIN check and it looked like it visited a BMW dealership in August 2007. Water pump was replaced around 95,000. No mention of the belt though. 7 years/50k miles on a belt has to be literally stretching it.

[Todd Black 88]

The cabby I bought with 140,000 kms was on its original belt.

[dnguyen1963]

Most Japanese cars can last up to 150k, but for E30s with frequent high revving the belt should be replaced every 20k. It all depends on how the car is driven.

[lcoleman]

It's absolutely possible. The maintenance schedule is emphasized because failure is so catastrophic if the belt fails.

I'd buy it and drive it home without too much worry, then change it immediately after. Of course, with my luck the belt would snap as I was pulling into my driveway.

[Ether-D]

My 4runner has 185000 on the original t-belt. I think it's non-interference, so I'll get to it one of these years…

On the e30s, every 50,000 or less or your money back.

[Gary Yogurt]

I'm hoping I can dig up some records when I visit. Best case scenario the belt's a hair under 50,000 miles but about 7 years old.

It would be a 150 mile trip back home.

It would probably be the most nail-biting driving experience of my life if I drove. I'll see how I feel. I might end up having it towed.

[spdracrm3]

belt longevity has a lot to do with how hard the belt has to work , on the e30 m20 with only two valves per cyl ,large heavy valves that are on a high lift short duration cam works a cambelt very hard and BMW valve springs are appropriately stiff for this reason.all making the belt work hard (same as a porsche 944 2.5l 2.7 3.0l 4cyl that had 40,000 mile belt interval,if it snaps it scraps the head)

In comparison to todays multi valve engines with lighter valves and valvetrain with lower lift longer duration cams (for today emissions standards) and most being non-interference the cambelt are not stressed nearly as much(you can turn cams by hand on most at cam pulley) ,such that you see much longer timing belt change intervals.maintenance plays a large part too ie oil changes

we have done T-belts on cars at our shop that were over double the change interval come out looking like new and done some right at the interval come out looking ready to snap .

[ttrousdell]

my 90' 325 went 105k and the belt snapped. Bought it and 3 weeks later it went on me. shitty luck.

[Gary Yogurt]

Moot point now. Shitty seller sold the car after agreeing to sell it to me.