Timing Belt Woes

[JimInRadfordVA]

I have a 1995 Volvo 960 that I bought used a few months ago. It's been running great and I've been slowly rehabilitating it. One day, after I came home, I went to go back out and run an errand. The engine cranked, but would not start. I looked under the hood and found the timing idler wheel sticking out of the front cover. It had drilled out a perfect hole. I can only assume that the timing belt has broken or is otherwise disengaged.

Now, the big question: the belt did not break while it was running--it broke when I tried to start it. Has there been catastrophic damage done to the valves and pistons?

I know that I can get a "timing belt set" (belt, tensioner, idler, water pump, cam and crank seals, etc) for about $400. If I can reasonably expect to replace the timing components and drive off into the sunset, I'll go ahead. If I'll need to pull the head, I'm calling the towtruck and have it dragged away.

What say you all?

[danr960]

Most likely the a valve or more are bent. But, it may be worth just buying a belt and see if you can turn it over by hand, without spark plugs. I have heard of someone having a similar episode on a bulletin board and was able to replace the timing belt and have the engine run afterwords, but the others needed to have the head repaired.

DanR '94 964 361,000 miles (127.000 on the new engine)

[JimBee]

Since you are at peace with parting with it if there's internal damage, I would get an idler from the junk yard and buy a new belt. Spin the pulley before you buy it and see if it has any angle play. Check the tensioner pulley on your car, too, to make sure it turns freely'; you might want to replace that with a junk one if it seems to loose or bound up. You might even find a good belt; I've seen some on junk cars. Get the belt cover while you're there. Spin your car's water pump too to make sure its free. Put it together and try to run it. If it runs o.k., invest in some new components and you're off and running. If not you're out a few bucks for the test.
Good luck.

BTW: The complete OEM roller kit minus the "damper" (hydraulic piston) at Borton Volvo in Minneapolis cost me around $200.00.

[Choguy03]

The problem you will have is holding the cams in place while doing the timing. I think this is a bigger issue, and most likely a head rebuild is in order. Even if you weren't driving the engine, when you turned it over it probably bent some valves. The pistons should be fine, maybe a ding or two, but nothing terrible.

[rspi]

You have about a 5% chance that the motor is fine. I would get a belt and NEW idler, put it all together and see what happens.

Did the roller come off? Did the belt break? Did you hear squeeking months before this happened? If the roller came off, and the belt came loose, and you tried to start the car and the belt did NOT turn the cams, you are probably ok.

[rspi]

Oh, almost forgot. I never do cam seals if they are not leaking. Get a kit with rollers, belt and tensioner. I never do a water pump that isn't leaking as well.

[Eskimo]

We also had the tensioner wheel burrow through the plastic cover of our 97 960. My son stopped at a gas station, filled up and then the car wouldn't start. He cranked it several times before deciding to look under the hood, then noticed the hole and the pulley lying there. After towing the car home, we pulled the cover off. The tensioner was the only thing broken, but the placement of the timing marks didn't look right. I got another tensioner and took a chance moving the engine and lined everything up. I was able to turn it by hand and did the mandatory 2 rotations with marks staying in place. The car would then turn over, but not start. I checked the compression and every cylinder showed zero. Does that mean that a bunch of valves are bent or is it possible to have one of the cams in the wrong position (if the marks are lined up)? Thanks.

[billofdurham]

To do damage to the valves or pistons the engine doesn't need to be running. Cranking it moves the pistons but the valves will not be moving and they will collide.

Bill.

[Eskimo]

So, valves and or pistons were probably messed up when we didn't realize there was a problem and tried to start the engine?

[billofdurham]

Very likely.

Bill.