JetSkiRookie

[JetSkiRookie]

Robraider left this homepage in a response he gave me to a problem I am having with a 92 Polaris 650Sl engine coupling removal.

I have just removed the driveshaft from 92 Polaris SL650 and, as expected the front spline (connected to rear of engine) was stripped. Now the problem is replacement of the engine rear coupling. It is froze in place. The service manual indicates to place a rope in the rear cylinder head and turn the engine coupling counterclockwise. Well, I made all the way to placing a wrench on it and putting all the muscle I had and I still hasn't broke free. I have added some WD40 and Liquid Wrench to the coupling yesterday hoping this would help. But it is still tight this morning.

Rob indicated I needed to get a fly wheel holding tool. then get a pipe wrench to remove the bad coupler and use a cheater if neded. He also indicated I could use a little heat.

Questions:

1. Am I turning it the right direction. I am assume counterclockwise is referenced from looking from the rear of the engine....is this correct?

2. Should I heat up the flywheel, so that it expands and not the coupling? Also, can I use a propane torch and will this cause any problems internal to the flywheel?

3. How much pressure (torque) should I expect to use. I am concerned about damaging the cranckshaft or pistons.

Steve
p.s. I am using a Crescent wrench since I do not access to the special tool that slides into the coupling....

[Bryan Glynn]

You will probably have to remove the engine from the hull, first of all. Sometimes they are REALLY on there good!

Since you will be running this engine again, don't use the rope method, if it's on there that tight - you want to use a special flywheel holder as Rob mentioned - otherwise you can twist your crank.

You put the flywheel holder ont he front flywheel, but the heat goes on the COUPLER, not the flywheel. Try 15 seconds or so of propane right on the coupler and see if it loosens at all. Yes, you probably will need a pipe wrench and a 6' cheater bar.

[JetSkiRookie]

Too late, I already followed the service manual and inserted a rope in the rear cylinder head. I took it out though.

Is the coupling threaded on the inner diameter or outside diameter?

Also, is there anything else I can do short of removing the engine from the hull...how about supporting the flywheel on the rear to hold the shaft from turning....

Is this flywheel holder something I should be able to rent at a boat shop?

Thanks

Steve


<blockquote>quote:</font><hr>Originally posted by Bryan Glynn - SBT Webmaster:
You will probably have to remove the engine from the hull, first of all. Sometimes they are REALLY on there good!

Since you will be running this engine again, don't use the rope method, if it's on there that tight - you want to use a special flywheel holder as Rob mentioned - otherwise you can twist your crank.

You put the flywheel holder ont he front flywheel, but the heat goes on the COUPLER, not the flywheel. Try 15 seconds or so of propane right on the coupler and see if it loosens at all. Yes, you probably will need a pipe wrench and a 6' cheater bar.<hr></blockquote>

[Bryan Glynn]

Don't worry about damage at this point - you haven't been able to wrench it enough to do anything yet.

I say you will probaby need to remove it, simply for room to work and leverage.

The coupler is the female end.

I don't know if you could rent a holder - I suppose there may be some type of universal holder out there...not sure though.

[JetSkiRookie]

Two final questions on this subject...

1. I am turning counter clockwise referenced from looking from the rear of the engine....is this correct?

2. If the rear flywheel and the coupling one unit on this 1992 Polaris or should the coupling come out with the flywheel in place

[Bryan Glynn]

Correct, and one unit, yes. Just to clarify - when we are talking about a flywheel holder - we mean the front (MAG) flywheel.

[SeaLion]

Yes you have to turn counter-clockwise as viewed from the rear. You are actually supposed to remove the coupler before removing the engine. The reason is that with the engine still in place, it is bolted to the hull and at the motor mounts and won't move on you.
The procedure is to bring the pto piston 1" from tdc. Insert a 1 foot piece of 5/16" diameter nylon rope and rotate the coupler counter clockwise until it traps the rope. Use a large crescent wrench if you don't have the Polaris tool and turn counter clockwise. It should loosen up. I swapped couplers before and it worked fine for me. I did have to use a really large crescent wrench which had lots of leverage.

[JetSkiRookie]

Thanks for the advice....it is really on there

Steve

[JetSkiRookie]

Folks, Thanks for all the advice. I followed the service manual to a the "t" and it came off with 1 1/2 ft pipe wrench and a 1 foot cheater.

I final comment. I had to remove the back motor mount bolts and left the rear about 1/2" to unscrew the coupler....the reinforcing fiberglass section in the hull was stopping it from being unscrewed!

Steve

[SeaLion]

Amazing what a little leverage will do You must have that huge frisbee looking coupler if you have a 92? I can see how things might be in the way of that sucker.