MS661 case gasket

[Dustin4185]

Well, I screwed up and let a coworker borrow my 661. He has ran saws a lot and didn’t think it was a big deal. Well, he has had it a while and just retired so he brought it back to me last week. I sat it in the shop and didn’t really have a need for it until today. Grab it up and bar oil is everywhere. I laid it on the side because the stupid caps always leaked anyway. Thinking it was leaking through the oiler or somewhere else since it was cold and the shop gets heated during the day I didn’t think anything of it. Fast forward to sharpening the saw and see a piece of case gasket sticking out. It is down low and I’m not sure if that’s where the oil was coming from, but could it be? A lager piece broke off, but you could tell it went all the way to the edge of the case before. He offered to make it right, but not sure if that is where it is leaking from.

 

[Stem]

I'd venture to say that's the problem. maybe pressure test the oil tank to see if it leaks where the gasket is blown out.

 

[Dolkitafreak]

Put gas in the oil tank and hold the saw on its nose, the lower viscosity liquid will drip through quickly if it’s leaking there!

 

[huskihl]

I wouldn’t think it’s anyone else’s fault. Sometimes it just happens

 

[Dustin4185]

I wouldn’t think it’s anyone else’s fault. Sometimes it just happens

That’s what I told him. I will check it out and see what needs to be done. It will be my fist split if it is leaking.

 

[huskihl]

That’s what I told him. I will check it out and see what needs to be done. It will be my fist split if it is leaking.

Folks wonder why I use a sealant on case gaskets. That’s why

 

[redline4]

Sausage grease is the new Dirko.

 

[huskihl]

Sausage grease is the new Dirko.

Don’t knock it till you’ve tried it, big boy

 

[Stump Shot]

Sausage grease is the new Dirko.

Don’t knock it till you’ve tried it, big boy

In some older Husqvarna manuals they actually recommend using grease on the case gasket.
Best I can figure is, it might help the gasket not tearing if the cases shift a bit, but they never said why.
Saws that this was done to from the factory sure makes it easy, the gasket comes out in one piece. 2100CD comes to mind.
Personally, I've tried it every which way that can be done and have come to the conclusion that truing up any warpage on the exposed case haves with a piece of glass with sandpaper on it does more to save a failure than anything when rebuilding. As the metal won't move as much the second go around after its initial warp.

 

[NPKenny]

... I've tried it every which way that can be done and have come to the conclusion that truing up any warpage on the exposed case haves with a piece of glass with sandpaper on it does more to save a failure than anything when rebuilding.

Every time! I have a mirror I hang on the wall in my shop. I take it down to true up the case halves prior to reassambly.

Also, I would be hard pressed to "blame" anyone for a leak there. If the case isn't broken or there are not signs of abuse, this is just a wear item. Time to rebuild and go again.

 

[Stump Shot]

Every time! I have a mirror I hang on the wall in my shop. I take it down to true up the case halves prior to reassambly.

Also, I would be hard pressed to "blame" anyone for a leak there. If the case isn't broken or there are not signs of abuse, this is just a wear item. Time to rebuild and go again.

I agree, it would have to come back with no paint on the bar and turned blue before you could say there was saw abuse.

 

[Redfin]

The oil tank is above the bevel on front. Flip the saw over, you will see what I mean.

 

[Creaky limb tree care]

It's more likely, that the crankcase is cracked around the bar mounting studs, quite common on this model sadly!

 

[RedFir Down]

I've had to split and put a new case gasket in 2 661's from the gasket being pull out in that same spot.
I hope your leak isn't coming from there.

The oil tank is above the bevel on front. Flip the saw over, you will see what I mean.

You're right, it looks like its right at the corner of the reservoir.

 

[RedFir Down]

@tree monkey
Scott, have you seen this being an issue?

 

[Dustin4185]

The oil tank is above the bevel on front. Flip the saw over, you will see what I mean.

That’s what I was thinking. I’m going to put some UV dye in the oil and see if I can find the issue.

 

[Dustin4185]

It's more likely, that the crankcase is cracked around the bar mounting studs, quite common on this model sadly!

Shoot, I hope not!

 

[Dustin4185]

Every time! I have a mirror I hang on the wall in my shop. I take it down to true up the case halves prior to reassambly.

Also, I would be hard pressed to "blame" anyone for a leak there. If the case isn't broken or there are not signs of abuse, this is just a wear item. Time to rebuild and go again.

I wasn’t blaming anyone, he just asked if it was something he did. Don’t think it was anything he really did to cause it.

 

[Loony661]

A good way to test where it’s leaking from is to wash the saw with grease cutting soap (Dawn) and hot water, and a good brush. Blow it dry and set it on a clean piece of cardboard over night. The residual water that drips will dry by then and any oil will soak into and show you where to start looking. You might have a couple light spots from residual oil you couldn’t remove from cleaning, but an actual leak will show itself as a darker, wetter spot. Hope this helps.

 

[Creaky limb tree care]

Shoot, I hope not!

Me too!