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Old 08-16-2004 | 01:18 PM
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Default Re: Snapped Timing Chain?

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.
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Old 08-16-2004 | 01:22 PM
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Default Re: Snapped Timing Chain?

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.
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Old 08-16-2004 | 02:04 PM
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Default Re: Snapped Timing Chain?

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...
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Old 08-16-2004 | 02:47 PM
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Default Re: Snapped Timing Chain?

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
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Old 08-16-2004 | 03:02 PM
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Default Re: Snapped Timing Chain?

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
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Old 08-16-2004 | 04:06 PM
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Default Re: Snapped Timing Chain?

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.

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Old 08-16-2004 | 04:21 PM
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Default Re: Snapped Timing Chain?

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




fingers crossed for an easy fix
 
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Old 08-16-2004 | 09:54 PM
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Default Re: Snapped Timing Chain?

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???
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Old 08-16-2004 | 10:42 PM
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Default Re: Snapped Timing Chain?

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.
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Old 08-17-2004 | 06:45 AM
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Default Re: Snapped Timing Chain?

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.
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