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Johnny B
01-14-2005, 08:33 PM
My 90 E34 525i died in the post office parking lot today. It sounds and looks like the timming belt may have broken. The car made it to the parking lot I did my mailing and came out but as I tried to start it sounded real funny like it had no compression. I pulled off the oil fill cap and I could not see the cam moving. I'm wondering if a timming belt failure is a for sure valve and head job. The motor never started or ran after the belt broke, but I did try to start the motor a bunch. The fan was turning so I know the crank was turning. I had it towed back to the house and will make a compression check Sat. to make sure it's the belt. Does a broken belt always mean a bent valve. I can replace the belt myself but don't have tools and shop for a head job. If it's a for head job sure I'll won't waste my time just replacing the belt. Help me out with what I should do?

Johnny B

Rigmaster
01-14-2005, 08:39 PM
Count on at least 1 or 2 bent valves. If you're lucky, that's all the damage that was done, and you can get by with having the head redone, then you'll probably be good for another 100k+, as long as you don't break another t-belt.

Don't bother with a compression test, just take the distributor cap off the front of the engine, and see if the distributor rotor turns while trying to crank the engine.

Replacing a head is not TOO tough, if you have some basic mechanical skills you can do it. A good machine shop is a necessity though!!! Post back here or email me directly if you need some encouragement!!

Bret.