Lmarth

The valve covers aren't going to tell you anything???? If none of the rockers are going up/down, the timing chain broke. If only the front cylinder's valve train is functioning, the cam broke. Please enlighten us Tempest.

z.zuperboat

You Can Remove The Timing Cover Without Dropping The Pan.just Loosen The Pan Bolts And Pry Down Alittle.have Done It Many Times.reinstalling I Nip The Ends Of The Cover Where It Tucks In.

Pat McPherson

Just talked to the engine builder that did my cylinder heads. He has no clue if there is enough piston to valve clearance for the engine to crank out of timing without collision. He did agree that the damage has already been done. Told me the first thing he would do is pull the valve covers, loosen the rockers, then put air to the cylinders. If she leaks the valves got hit. If not, she may be salvageable...

Lmarth

Patrick-- Your engine builder makes good points. You'll have to take it one step at a time. If you're really lucky the valves didn't get bent. A lot has to do with how aggressive a cam (lift) you're running and compression ratio (dome configuration). I once saw a dropped valve just bounce off the dome of the piston. The valve hit the piston square and did virtually no damage! Keep us posted

zzzzzz

Pat,Just an idea but I did a timing chain and gear job once too find out it was the 10 cent roller pin that holds the gear onto the shaft that was not noticable until you put some force on it and then you could see the shaft spinning inside the gear. I know its a long shot but just thought I would pass it on because it cost me $250 and a Saturday. Good luck. Tom

robyw1

I would think that if the pistons hit valves that the engine still would not turn over so easy. I have also seen the problem that zzzzzz mentioned in his last post. I would first call mercury and ask if the 7.4MPI 310 engine is an interference engine. However perhaps he may not even know.

Roby

rookie_j

had the same thing happen as zzzzzz, broken rolled pin in the distributor gear....




fingers crossed for an easy fix

Pat McPherson

Well Guys, I started tearing into it.
Pulled the water pump and balancer before it got dark.
Have not gotten the timing cover off yet but I can see inside.
The chain is definitely off or broken. The gear on the crank is stripped.
Things are not looking good...
I guess tomorrow after work, I'll work on loosening the pan so I can get the timing cover off. Then I'll work at getting the valve covers off. Lots of stuff in the way.
Seeing the stripped gear on the crank has got me thinking the cam is locked up... Anyone else got a guess???

Tinkerer

Don't waste your time - Just pull the motor. It is going to have to come out no matter what.
It will be alot easier to pull it apart on the stand.

Pat McPherson

Yea, I am sure things are quite ugly inside...
I'll screw around with it a little more tonight then yank it over the weekend.
Looks like my season has ended about two months early.