Mark A 91Formula

iTrader: (3)

I know it possible but how often will a broken timing chain cause other damage to the engine? I've had it break on many differant cars and it was always a simple matter of replacing the chain or belt, never had it take anything else with it.
Now a friend, a girl who knows nothing other than where to put the gas, has a car in the shop, 86? Olds with a v6 and the mechanics are saying the timing chain broke and it needs a new engine. I'm going to see the shop personaly in a few days but my initial reaction is to call sounds like they wanna replace the chain and get a few grand out of her.

RedFirebird

Yeah its possible that she needs a new engine. If the timing chain broke its possible a valve (or two or three etc) kissed a piston. The cam stops but the crank doesn't in many cases. If you had little pieces of metal bouncing around in the cylinder before the engine stopped the block could be toast. I'd ask them to pull the heads off the motor and you take a look yourself to see if the cylinder walls are damaged, or you could also do a compression check of all 6 cylinders.

Mark A 91Formula

iTrader: (3)

Wouldnt it be impossible to do a compression test with a broken timing chain? If the cam isn't moving neither are the valves, cant build compression if the valves stay open

SoCo80p

iTrader: (5)

its VERY unusal for a timing chain to snap, they just really stretch out, even if one did snap it wouldnt do anything really bad, its only on multipul valve engines it causes serious damage/

ChevyLuva3

Whens a good time to replace the timing chain? I wish those things would give you warnings, all I've heard is if your car is hard to start... (remember to put key in the on position, wait the fuel pump to get ready, then turn the key)... but if its hard to start that could be a sign of a wearing chain, and time for replacement. Its a very "in depth" job, and its for such a little thing, and it doesn't make your car faster, so people usually don't change them much... any way when should they be replaced mileage wise? Whats a good way to tell its on its way out?

fb305svs

The ONLY reason that engine would need replacement is if its an "interference" motor. The number of valves rarely has anything to do with it. However, typically, 4 valves heads are more likely to be interference. In your case, i would call extreme bull****. here are some ways to find out if its damages internally or not.

Who ever was driving the car when it died, ask what kind of noises did it make. if she says a loud tapping noises, then that could have been the valves hittin the pistons.

Also, if they really think its the motor, insisit on having them pull the heads. If they won't, then take it elsewhere. You could also ask them to turn the engine over by hand. The engine will want to stop when it contacts an open valve. Tell them to do it with the spark plugs removed so you can also inspect the spark plugs. Also, tell them to do it with them removed so that you will know what the resistance to turning the motor over will be. With the plugs in, there will be points of resistance from compression.

I do however think this is a typical cas of bull****. Its not an over head cam motor, and its a gm v6, which if i remember correctly, could valve float all day long and not have anything to worry about except poor gas mileage and a spun crank or rod bearing.


Steve

SSC

If it is an interferance engine than the bottem end should be fine she's probably going to need a set of heads although the pistons got hammered by valves.

Although, its quite possible a valve hit hard enough to pop through the piston or cylinder wall causing internal damage. (looks like a grenade blew up inside the cylinder)

Asking these questions for a friend is useless. You werent there and dont know what they said. Its possible they told here due the to cost of new/used heads / machine+ labor, tearing the timing chain out+ labor (it should be a chain not a belt) its more cost effective to replace the engine. This is true and probably what they told her and I agree,. Its cheaper now and better in the long run to replace the engine instead of patching it togather.

Now if this is a non interferance engine (Im thinking it is) then this shop is full of it and they need to get this car out of there ASAP. But call a few places up and ask if this this is a interferance or NON engine. That is what matters.
SSC