Replacing Flywheel on gm 5.7

texasrebel75

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Joined
Apr 6, 2009
Messages
3
I have a 1984 mercruiser GM 5.7 liter. Not sure what drive. the problem is broken teeth on the flywheel and they are tearing up starter gear teeth. question is what is the best way to remove the flywheel for replacement? Does the engine have to come out? On that model is it one piece flywheel or ring gear? And whats best approach to pulling engine if neccesary? Boat is 1984 sea ray sundancer 260. Any info would be much appreciated.
 

HT32BSX115

Supreme Mariner
Joined
Dec 8, 2005
Messages
10,083
Re: Replacing Flywheel on gm 5.7

Howdy,

You will be pulling the engine.

You can buy a ring gear from Napa, or any autoparts place and have a machine shop replace it.

You may need a new/rebuilt starter. it will need to be a marine unit.


Check the "Adults ONLY" stick above in the main (Mercruiser) forum. You can find a service manual there.

You will need to pull the drive before you remove the engine


Regards,


Rick
 

fcawth

Seaman Apprentice
Joined
Feb 16, 2009
Messages
44
Re: Replacing Flywheel on gm 5.7

If you can pull the engine and get the flywheel off, you can replace the ring gear yourself. No need to replace the flywheel. Just drive the old ring gear off with punch, and put the new ring gear in the oven at 450 for 1/2 hour or so, take it out and put it right onto the flywheel and it will go on easier than you think it should. Once it cools it will be press-fit on there. I put my flywheel in the freezer (in a bag :) ) just to be sure.


I just did this, and I thought it would be much more difficult.

Fred
 

texasrebel75

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Joined
Apr 6, 2009
Messages
3
Re: Replacing Flywheel on gm 5.7

Thanks for the info guys. I have pulled many engines from cars and trucks but never from a boat. I am concerned about doing it. I do have an automotive engine hoist but can't see how I can use that. Even in the back of my truck I doubt I can get the height necessary. Boat is on the trailer. I have seen some pics on here of guys using an A frame and chain hoist.
HT you said I need to remove drive, do you mean the outdrive that goes through the transom? If so that seems a little beyond me. I am starting to wonder if it's time to consuult a shop. Wondering about the price range I am looking at to have it done? I am on a pretty tight budget though. Anyways thanks for the help guys I'll try to keep ya'll posted on the outcome.
 

Bondo

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Staff member
Joined
Apr 17, 2002
Messages
71,095
Re: Replacing Flywheel on gm 5.7

do you mean the outdrive that goes through the transom?

Ayuh,... You've gotta tell Us what it Is...

Removing the drive is only 8 nuts,+ a $7.00 gasket kit on some drives....
 

45Auto

Commander
Joined
May 31, 2002
Messages
2,842
Re: Replacing Flywheel on gm 5.7

If you're capable of removing the engine, the removal of the outdrive is pretty much equivalent to the removal of the air cleaner - not much to it!
 
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