91' 3000GT questions


Ok… this might be long or not i dont know. I got a 91 3000GT SL. As of now its the best yard ornamint you have ever seen. I was driving it, not pushing it hard, and it made a pop. Not too loud. The car cut off and I rolled to a stop. I thought the worst. It didnt smoke, leak oil, or anything. I havent hand cranked the engine yet but it wont turn over at all. All I get is a clicking noise. The one problem the car had was a lifter knocking in the front cam. Wasnt too bad but it was knocking none the less (the first gen 3000’s had tiny lifter ports and cause problems). So, what could the problem be? My best guess is that something in the cam broke and locked it up though Im no expert on engines. The timing belt is in good condition and nothing seems broke. The worst thing that I can think of is a piston or rod messed up somehow and locked it up. Or could it be electrical? Does mitsubishi have some kind of fuze to burn if the engine reaches a critical point to protect it? Im afraid im gonna have to replace the engine. Id like to salvage what I have and fix it and not spend a fortune but Im also tempted to find a different engine to put in but thats alot more work than what I want.

Thanks, Joe


[b]The problem might be that the timing belt broke. And since this is an interference type engine, it could be that one of the pistons is pushed up against one of the valves. And now the engine won’t turn over.

The first thing I would do is remove the upper timing belt cover and see if this is what has happened.



You’re going to have to try turning the engine by hand, with a wrench on the crankshaft pulley, to determine whether or not it’s locked up.

Removing the spark plugs will make this a lot easier. If the engine rotates, consider yourself lucky. If it doesn’t, don’t force it.

A failure in the ignition circuit or the fuel pump circuit would also cause the engine to stop running, but it would not make it impossible to turn with the starter.


The timing belt is fine. I took the cover off first thing and it looks new. As far as the piston hiting the valve I believe thats what has happend due to the lifter knocking.


[b]Then the next thing to do is remove the valve cover and if there’s anything obviously wrong. Such as a broken camshaft.



Did you remove the entire timing belt cover? The majority of the time the teeth strip off the belt at the crank shaft. The top half can look fine and the bottom half could have no teeth. The easiest thing to do at this point is to use a breaker bar and socket on the crank bolt. Attempt to turn the crank clockwise while watching to see if the cams turn. Do not force it.


That shouldnt keep the engine from turning over though would it?


This is an interference motor. If the cams and crank do not turn together the pistons hit the valves and the engine either stops turning, busts holes in the pistons, or breaks the valves.


he said it was fine, and if a piston hit a valve, you can be sure it cracked it.