Blown timing belt? Probably

Hey guys, I’ve got my sister’s 1995 Dodge Neon with the 2.0L SOHC. While driving it recently I heard a horrible squeaking noise then a ZZZZZZzzzzzz sound. I immediately pulled over. The check engine light came on, and I shut the car off. Coolant was all over the place leading me to believe the water pump failed. I had it towed to my house, and now I will have it towed to the shop to get fixed. I would like to have them repair the timing belt and water pump. However, I am afraid that the valves were beaten to a pulp and now I will need a new engine. I was only going 35 mph when it happened. What are the odds that my valves were smashed up, and is there anything I can do to check them before I pay for a timing belt/water pump repair?



Thanks in Advance!



--Max

If you had to shut the engine off then your timing belt is ok. The engine can’t run without the timing belt.

Have you looked over the engine closely? Are all the belts there and ok? How about the coolant hoses?. Radiator cap?

If everything looks ok, I’d try starting it to see what is happening.

The sequence of events is not totally clear to me, but the speed at which you are driving when a timing belt snaps is irrelevant.

Even if an engine is idling when a timing belt snaps on an interference engine, the valves (and possibly pistons) will sustain damage.

If the timing belt really did snap, this 16 year old car is not worth the cost of repairs, unfortunately.

If the motor is not an interference motor, the valves are ok no matter what happened.

If it is an interference motor and you shut the motor off by turning the ignition switch to off, then the timing belt didn’t break. If the motor locked up suddenly and shut itself off, it is highly possible the belt broke.

It is an interference engine.

The way you tell the story does sound as though the water pump has failed, but rather than tow the car to a mechanic and tell them to replace the timing belt and water pump, why not tow the car there and tell them to find out what happened to it? Tell them what happened and have them diagnose the situation as a whole. There are two things you need to keep in mind when dealing with this situation, though:

  1. DO NOT turn the key!!! Doing so could destroy the engine if the deed is not already done. You have a much better chance of ending up with a repairable situation if you follow this simple instruction. Pass this on to the mechanic you will be using also. Don’t let him turn the key either until he finds out what happened.

  2. If the water pump did fail and you have suspected valve damage, DO NOT let the mechanic tell you the only way to find out if there is valve damage is to replace the timing belt and water pump and try to start the engine. This is, for some unknown reason, a common misconception in the auto repair industry, and the people who believe this are, frankly, an embarrassment to the profession. If they tell you this, ask them why they don’t simply check the valve lash or perform a leakdown test. Either test takes about a half hour to perform and will tell your mechanic whether or not there is valve damage. Odds are, if you pulled the car over and actually shut off the engine, it is highly unlikely you have valve damage.

Ask for a diagnosis.

Are you really that confident about the results to the tests you speak to tell someone “OK your belt is broken,my tests reveal all that is required is a new belt (and possibly water pump and tensioners) I guarantee if you buy this belt job from me and after we start your car there is a second issue, I will fix it for free,parts and labor”.Do you feel confident enought to make this statement?

I would maybe make this statement with a higher quality car that I had a good history on. With this one it’s, I fix the belt,get your car running,and we go from there,take it or leave it.I am not getting maried to this Neon over the money I make putting on a belt.

Without seeing the car I could pose the following.
The squeaking could be a seizing water pump and/or slippng belt which may not do any engine damage.
The ZZZZZZZzzzzzzz sound could be the point at which the belt may have grabbed hold and started shearing coolant saturated belt teeth or it could be the sound of valves brushing piston tops. The end result would be the same.

Do NOT allow a shop to tell you that you will have to spend XXX dollars to replace the T-belt, etc to determine if any engine damage is present. This can easily be determined with a few minutes of time.

Good News everyone! I had the car towed to my mechanic, They told me it was indeed a blown timing belt. They found a new motor with 69,000 miles on it to put in for $1400 or to diagnose engine damage with a compression test (and I assume other tests) for $150. They tested the engine and they said that there was no engine damage and that a new water pump, timing belt, serpentine belt and coolant would be $450 even and knocked the diagnosing charge off.

Was this the original timing belt? How many miles was on this timing belt?

Now the question is,how does an interference engine not get damaged when the timing belt breaks" (I know the OP says the belt was “blown”). Second if a belt is broken the car shuts its self off (as has been pointed out).Rather than dwell on these issues, I say we just move on.

This was the second timing belt this car had. It was replaced at 60,000 miles. The car currently has 74,000 miles.

I honestly do not know. I shut the car off as soon as I knew something was wrong (the car did not stall immediately). Maybe the gods were looking down upon me, or maybe I was lucky. Who knows…

The engine would die immediately if the timing belt broke and the valves would be smashed. I doubt we really know that the belt let go.

It’s rare, but it does happen. It happened to me once. Timing belt broke…engine was interference. It broke just as I was starting to go from a stop-light…Didn’t know what happened at first…Had truck towed home…and after about 20 minutes I discovered the belt had broke…I was all prepared to replace the belt and pump the following weekend. Now I had to do it sooner. So I decided to just put the new belt on and see what happens…Truck started up…and drove great for another 100k miles before I had to replace it again.

Engine died immediately, correct? You didn’t have to shut it off.

If I read the post correctly, you shut the engine sown because the water pump blew. When you immediately shut the engine down, my guess is that the crank was still turning the camshafts. I suspect that OK4450’s description of what happened next is probably spot-on.

Kudos to the shop for being honest, by the way. We’ve heard a lot of stories here about shops that would have insisted you needed a new motor without even checking.

Happy motoring.

Keep going to this garage. I’d say the mechanic has more than earned your trust by being honest about the condition of your valves, but I’d add that he or she is actually looking out for you. They performed a fairly labor intensive job at a very fair price. I hope you tipped the mechanic. If you didn’t, go back and do that. Buy your gas there if they sell gas.

I blew a timing belt in a 93 Eagle Talon (an interference engine) with no damage to the valves. It’s not automatic. In fact, I suspect that this problem may even be assumed and that little diagnosis is ever done.
My car was under warranty. Suddenly the failure of the timing belt did not automatically require a new engine.