Prism killer

my son owns a 97 Geo Prism with about 95K miles on it. A few weeks ago he was involved in a fender bender (relatively minor, the other driver’s fault, still driveable) and recently took the car in to have the right front fender repaired. Immediately after picking up the car from the insurance company he noticed some strange noises coming from the engine compartment. Since they were not particularly loud he kept driving, assuming it may be the new fender “settling” (ok, he’s no mechanic). After approx 20 minutes he turned into a parking lot and noticed that the power steering was not working. At that point he was nervous about driving the car any further and called the insurance company claims center. He described the problem and asked the rep what he should do and the rep said to return it to the claims center. My son was nervous about driving the car but the rep told him it would be ok.

Shortly after he resumed driving steam began billowing out of the hood so he pulled over and also noticed fluids were leaking onto the ground. He got the car towed back to the claims center and they initially told him they thought the problems were a result of the collision or the repair and gave him a loaner car. Shortly thereafter they called him and told him that they had taken his car to a mechanic who had determined that the problems were not the result of the collision or the repair. They told him a belt had broken and that’s why he had lost the power steering and also why the car had overheated.

I went with my son to look at the car at the mechanic’s shop. He showed us that the bolt that holds the pully on the end of the crankshaft had broken and said that it had probably been over-torqued, which would explain why the belt broke or came off and led to the overheating. My son had the car serviced about 20K miles ago and they replaced the belts, but I doubt seriously that the mechanic would have had any reason to tighten this bolt. I assume that this bolt has not had any attention since they built the car in '97. Since getting this broken bolt out of the crankshaft would be very costly they suggested replacing the engine with a used one from Japan at a price of around $3000.

I am no mechanic, but I have a hard time believing that this bolt just suddenly broke. Though the car is old, it has low miles and has been very reliable. My theory is that when they were repairing/replacing the fender, someone left a tool or part in the engine compartment and it got caught in the belt and broke the pulley. The insurance rep, the body shop owner and the mechanic are all very polite and pleasant, but I can’t help thinking they are taking advantage of my son.

Any thoughts?

Without car in hand it’s difficult to be exact about the cause of something like this but in most cases a broken crank bolt is often related to someone overtighening the bolt. It’s assumed, right or wrong, by me that the belts you mention also involved a timing belt.
If the timing belt was replaced 20k miles ago and someone overtightened the bolt it would be impossible to determine this now or hold them liable for it.

It also could be that the faint noise your son mentioned could have been the sound of a crank pulley that was slightly loose. This looseness can then lead to a bolt snapping off and possible damage to any keyways on the crankshaft.
Theorizing still more, it also could be that a faint noise could have been present for quite a while and gone unnoticed.
Sometimes after repairs many drivers become more sensitive to their vehicle and notice noises, vibrations, etc. that they had never noticed before.

The crank pulley could possibly be welded in place which would create problems if one had to ever go back into the belt cover for whatever reason but in my opinion would be a much better and far cheaper alternative than spending 3 grand on a 97 Geo.

Hope some of that helps anyway and good luck.

I’m inclined to say that the broken bolt is unrelated to the fender bender. Sure, it’s possible the additional jolt helped it along, but these types of failure are generally fatigue related and take many many miles from initiation to failure.

I also don’t think the bolt would have been tightened dusing the belt replacement.

I’m also inclined to say the loose tool theory doesn’t work either.

Overall, I’m going with one of those coincidences that happen to us all.


Your problem is that proving causation is going to be either nearly or completely impossible.

This bolt could have broken for many reasons. The mechanic who replaced the belts might have removed a bolt he didn’t need to remove, and if he over-torqued it, it might be the cause. It also just might be a simple case of metal fatigue, or it might have been caused by the accident.

Forget about proving causation, and point out to the insurance company that there is a correlation. Tell them the bolt was intact before the accident, and now it’s not. Tell them you expect them to fix this problem if they expect to keep you as a customer, and if they don’t step-up to fix it, it’s time to shop for another insurance company.

Sometimes the pulleys just break off. I guess we could say to never drive a car that’s making noise and losing fluids. It’s OK for them to say you can drive it as long as you are also paying for it. They sure don’t intend to pay for bad advice. I would call an auto recycler and take his offer and use the $3,000 on the next vehicle. After all, a 97 Prizm won’t fetch that as a trade-in.

I’ve seen this happen before.

I had a long time customer call me one evening saying that their vehicle had made a noise and stopped running. And since it was close to where I was located if I could come and take a look. I opened the hood and saw that all the drive belts were gone. Upon further inspection I found that the harmonic baalncer was missing. Once the vehicle was towed to the shop it was discovered that the crankshaft bolt sheared off. I know this bolt was never touched in the vehicles lifetime because it was bought new and then I took over servicing it once it was out of warranty. The vehicle had about 90,000 miles on it when this occured.

The broken bolt can be removed from the crankshaft by welding thru the center of a flat washer onto the broken bolt, and then weld thru the center of a hex nut onto the flat washer. Once everything cools down turn the broken bolt out by the hex nut.


broken bolt solution is genius. I’ll have to try that sometime. apparently a weld is strong enough for the torque required to remove the bolt. thanks!!

Not only does it work, but if space permits you to use a slightly larger hex nut on the washer, you’ll get more “bite” and be able to apply more torque, easing the bolt removal.

This car probably has the 4AC engine, unless it is a GT model which has the 4AGE. In both cases the belt pulleys are held onto the harmonic balancer by fours small bolts. The harmonic balancer and crankshaft sprocket are held on by on large bolt. The harmonic balance and the crankshaft sprocket are also keyed in place.

It might be possible to get the remaining threads out with a vice grip plyer if there is any remaining threads sticking out the end of the crankshaft. It might also come out with an easyout. Without the tension provided by the head of the bolt, it should come out easily. The real problem might turn out to be a damaged keyway, that would require replacement of the crankshaft.

If the keyway is damaged and you really want to get more service life out of this engine, I would start with a new timing belt and crankshaft oil seal. These engines have a history with this oil seal, it is easy to replace, but after tack welding the sprocket and harmonic balancer in place, you will never get to it again. I’d also put on a new timing belt because once the harmonic balancer is welded on, that the last timing belt it will see.

Then you should be good for 60-90 k miles or 6-7 years. Maybe more if your lucky.