Replace top end o-rings on liberty 600 - any tricks?

[fredster]

My wife's 600 has developed a small coolant leak where the PTO side cylinder and head meet. The top end was rebuilt last January by the dealer after an exhaust valve broke and took out the mag side piston. When I pulled it out this fall I noticed the overflow tank was low and during warm-up I found the leak. I called the dealer and they were pretty non-committal on covering this repair 10 months later so I'm going to replace the o-rings myself.

I have purchased all the o-rings for the top-end - cover plate, 1 for each spark plug hole and two each for the top of each cylinder.

It looks pretty simple from the diagram - drain coolant, remove thermostat housing, pull 12 bolts, and top plate and domes should come off. Remove old o-rings (hopefully find bad o-ring or reason for leak).

Is it really just as straightforward to replace the o-rings and bolt it back up? I know the six bolts per cylinder need to be torqued to 20-22 ft lbs and done in a criss-cross pattern. I also know I need to bleed the cooling system by raising the front of the sled and keep adding anti-freeze at idle until it comes out the bleeder screw by the thermostat housing.

Are there other tricks or tips? Common pitfalls? I did not find any evidence of people using any kind of sealer with the o-rings, maybe a bit of oil to make them pliable but nothing else. I'll use a bit of red loctite on the bolts, and will use a torque wrench to tighten.

If there are other things I need to be aware of I would appreciate the input - Thanks!

 

[nickelbagforme]

You've got it pretty well covered, still scratching my head about it leaking though after just being rebuilt. Clean everything real good, no sealant (little vasoline) or anything, look for any buggers on the mating aluminum machined surfaces (flat file smooth if need), any buggers could keep the surfaces from laying flat against each other. When you remove the 12 bolts try to see if any feel lose/tight compared to each other. Make sure to use a cross pattern (loosening/tightening) and work up to final torque. Look for cracks.

 

[indy_500]

my bet is that they overtorqued a bolt or undertorqued a bolt and you'll have a crack in the head, hopefully that's not the case, but you seem to got it covered. good luck...

 

[mikedrh]

There is no need to use any Loctite on those bolts. If the bolts come loose without Loctite they were not torqued properly.

The Loctite could be a problem if you ever want it apart again down the road.

 

[mjkaliszak]

As said above: 1) CLEAN,CLEAN,CLEAN 2) Decking or the deck surface is very impt. remove all burrs, I stone & lap on a surface plate with some 240-400 grit ( wet ) paper. It will show you where the high & low spots are if any. I also use WD to lap with or a thin light oil. If the bolts were over torqued they could have pulled a thread, created a burr ect... You have to get it all. It you have a damaged area by the o-ring groove that might allow leakage when things get hot & then cool also. 3) I always use O-ring grease , always , here are some in the pics . Vasoline will work also it's a highly refined grease. 4) Condition of the o-rings, inspect & make sure they are good , no cuts, not sheared ect... I believe those o-rings are very thin dia, like .070, handle with care. Hope this helps.

 

[fredster]

Thanks for all the input. I plan to do the job next Saturday and I will post my findings. When I look very closely, with a bright light, at the area that leaks there is just a hint of black sticking out. At first I thought it was gasket maker (which it's obviously not) but now I'm thinking they buggered up one of the o-rings when they put it back together. Hopefully it is really that simple. If I have a cracked head.....arrrrgggghhhh.

I am done taking any work to the shop that did the rebuild. This is not the first time I have had a new problem crop up that seems related to previous work they did.

And on it goes! At least I caught it pre-season.......

 

[doomsman]

There is no need to use any Loctite on those bolts. If the bolts come loose without Loctite they were not torqued properly.

The Loctite could be a problem if you ever want it apart again down the road.

I agree and a dab of never seize is always a good idea.

 

[michaeladams]

i agree with anti seize.dissimillar metals tend to react, corrode or freeze up

 

[doomsman]

Two more things.
you can find silicone grease at the hardware store for
the o rings cheaper than the auto store.
Also be sure to purge the cooling system well to prevent
hot steam pockets in the head.

 

[fredster]

600 Liberty top end coolant leak findings

I replaced the top end o-rings this weekend on my wifey's 600 Classic. You can see the problem that caused the coolant leak in the pictures. It looks to me like the mechanic wo did the top-end rebuild either didn't have the top cover o-ring positioned in the groove, or over-torqued the bolts, as most of the o-ring was found to be out of the groove. There was a few spots where it was almost severed, I'm surprised it didn't leak more. Ran about 250 miles this way last year and the coolant tank was empty....but there was still coolant up to the top of the cylinders. I'm just glad it didn't overheat, too....

Thanks for the tech tips. I used Dow Corning 111 grease on all the o-rings (I replaced the inner and outer cylinder o-rings along with the cover and spark plug o-rings) and carefully upped the torque wrench from 15, 20 and then 24 ft lbs. Followed the bolt pattern in my Polaris service manual. Also used anti-seize on the bolts. It all came together nicely. Cranked it up Sunday, let it run for a while and bled the cooling system. Had it warmed up nicely and no leaks! Nice to have it fixed.

Now we just need some snow.

 

[fishcrib]

I would show those pictures to the mechanic who rebuilt that top end. Tell them nice job...not. You are correct, at least you caught before it was too late.

 

[indy_500]

I would show those pictures to the mechanic who rebuilt that top end. Tell them nice job...not. You are correct, at least you caught before it was too late.

x2

 

[fredster]

Indeed....I sent a two-page letter to the service manager, with the pictures, and included the o-ring, and basically told them they blew it. I have spent a lot of cash with these guys over the past few years on both jetskis and sleds, service parts, gear, etc and this is not the first time they did something questionable.....I mentioned that in the letter, too. I also sent a copy to the sales manager that I have worked with in the past. Hasta la vista, baby.

 

[Nolimits]

Make sure to check the torque on those head bolts again after you have heat cycled that engine. The last time I had my heads off I forgot. I started shooting antifreeze about 5 miles down the road. Retorqued them in the bottom of the ditch and they haven't come loose since.

 

[fredster]

Thanks for the tip.....I'll take the torque wrench and socket along on the warm-up ride (hopefully in early Dec).