Lehman 120 Damper Plate Seized Engine

[jlees428]

Had the engine seize up on my friends marine trader when we tried to take her out fishing one morning and it would crank over very slowly or struggle to turn even an inch. Tried to bar it over and couldn't get it to move even standing on it. I first suspected hydro lock so I removed the rocker cover and injectors to no avail. I read on here about the springs on the damper plate falling out and jamming the fly wheel up and figured I'd explore that route. I disconnected the drive shaft from the transmission coupling and slid back the propeller shaft as far as I could and then used 8 inch slide bolts to open the bell housing. So it is definitely jammed up with springs. I have removed several pieces so far with a coat hanger and a metal hook and pick set through the gap in-between the flywheel and bell housing cover. I took the starter off and took a borescope and fed it down through the hole where the starter goes and there are all kinds of piece of metal shards. I think I can see the piece it's hung up on and have spent hours trying to pry it out of there while watching on the borescope. I am at the point where I believe the only way to get it cleared is to remove the fly wheel. Any tips on getting it off. I know it's heavy as hell and was thinking I could replace each nut I take out with with an 8 inch slide bolt like I did for the bellhousing. 6 bolts on the fly wheel and every two have a piece of metal under them that flares up on the ends right on the edge of the nut so i can not get a socket over it. How the hell do you get them out? Ill take some pictures to make it easy to understand in the morning. Any advice or information would be greatly appreciated. This is the first time I've ever worked on a boat or diesel engine so I'm a little lost on how to proceed. Thanks

 

[SteveK]

I have replaced two, both engines after one failed. I removed the trans completely out of the way.

Others have removed and replaced with the open space you are showing.

Your choice

 

[Comodave]

Welcome aboard. Sorry to hear about your problem. Maybe contact Brian at American Diesel. He is the guru on the Lehman engine.
804-435-3107

 

[jlees428]

I know I will have to move the transmission out of the way to take off the flywheel. I'm just trying to figure out how you get it off? I'm only able to get a socket 3/4 of the way over it the bolt heads due to the side of the bolt head having the obstruction of the metal shim that seems like it's bent up at the ends around the bolt. I'll take a picture of what I'm talking about in a few hours. I imagine they are on there to balance it?

 

[Delta Riverat]

I think those are lock tabs, you need to flatten them back down before wrenching.

 

[psneeld]

I had the same dampner issue.

I didn't have to take the flywheel off, just loosened the bolts and wiggled it with a crowbar to get the spring pieces out.

Then one at a time remove, locktight, tighten, then torque to spec.

 

[Bmarler]

You need to back the transmission away for enough to be able to get something to pry the lock tabs away from the bolt heads. I usually use a hammer and cold chisel to do that, but you might be able to just pry them away with a screwdriver. Those are torqued to a spec, so be sure to re torque them before setting the lock tabs again.

 

[psneeld]

Hmmmm....intetesting.....don't think mine had lock tabs.