Help!!?!?!?!?!?! Timing chain?!?!?!?!?!!?

**ResurrectedWS6** · 09-18-2012, 07:02 PM

I have a stock 1997 trans am lt1, 6 speed. I was sitting at a red light idling and I heard a "clunk" then it shut off. I tried to restart but only got a few exhaust pops. Pushed it into a parking lot and tested the fuel pump. It has 52lbs of pressure and is getting spark. Could my timing chain have broke? I did get on it kind of hard the day before and heard a faint squeaking noise near the water pump on and off the rest of the day. If it is a broke timing chain, would much damage be done to the valves/pistons being that I was at idle when it shut off/broke?

**98TransAmWs-6** · 09-18-2012, 07:11 PM

I seriously doubt it broke, they tend to stretch out or sag not break. What is your oil pressure? Is your car throwing any codes?

**ResurrectedWS6** · 09-18-2012, 07:19 PM

only codes it gave were for the cats being bad. no oil pressure now obviously because it will not start. but was between 30 and 50 when running. no engine noise or smoke before and no engine noise while trying to start, just spins over.

**Smittro** · 09-18-2012, 10:26 PM

I agree I doubt it broke. Whats your mileage?

They can "jump" timing if the wear is substantial, such as the sprocket teeth having heavy wear can sometimes allow them to slip.

If the chain had broke it likely would'nt even turn over as a number of your cylinders would close off.

Best to pull the timing cover and have a look.

**ResurrectedWS6** · 09-19-2012, 03:26 AM

150k miles. guy at the shop looked at it and said timing was lined up so he pulled tge plugs and said one was smashed and suggested it had dropped a valve. Now he says i should just replace the engine. I call BS because i would here rattling in the engine wouldnt I? Also, even if it did drop a valve, that wouldnt keep the engine from starting would it?

**ResurrectedWS6** · 09-19-2012, 03:30 AM

i feel like hes just trying to get more money, so im going to tow it home today and fix it myself. even if it were a dropped valve while idling, it couldnt have done enough damage to have to replace the engine.

**ResurrectedWS6** · 09-19-2012, 04:39 AM

heres a pic of the "smashed" plug.
http://i1079.photobucket.com/albums/...ps8d29d3e1.jpg

**Smittro** · 09-19-2012, 05:16 AM

If you did drop a valve, everything associated with that cylinder will be toast.

Piston, cylinder wall, the remaining valve, that section of the head.. Everything.

The entire combustion chamber for that cylinder will be damaged.

**Smittro** · 09-19-2012, 05:18 AM

Pull your rocker cover.. You'll know right away if it dropped a valve.

**ResurrectedWS6** · 09-19-2012, 05:25 AM

even at idle it would cause that much damage?

**Smittro** · 09-19-2012, 05:31 AM

Originally Posted by ResurrectedWS6

even at idle it would cause that much damage?

Sure can. 1000 rpm = ~16 revolutions per second.

**Smittro** · 09-19-2012, 05:37 AM

1000 revolutions per minute divided by 60 seconds in a minute = 16.6 revs per second.

**Smittro** · 09-19-2012, 05:43 AM

If you take 16 and divide that by the type of engine (4 stroke) which is 4 that's 4 reciprocations a second.

That gives you a good picture of how fast damage is happening.