Stihl 076 Oil Seals and worm gear

[Vintage Engine Repairs]

Hi gents,

I need to replace the oil seal that is leaking on my 076. It seems it’s just the one inside the worm gear, but I’ll do all 3 to be safe. Two are on the PTO side and one on the flywheel side

This saw has one large outer o-ring on the PTO side that seals onto the worm gear, any tips for removing and installing another? I don’t have a socket this big.

Also, it says to use a special installation sleeve for the worm gear so I don’t damage the larger seal when putting it on, but I can literally gently push the worm in and twist it with no resistance, is this installation sleeve essential?

Please can you advise if you’ve done this before?

Warm regards, Tom

 

[cbfarmall]

Just use a small hammer on the large seal and be very careful to start it evenly.

I've never used any installation sleeve for the worm gear. Never knew such a thing existed and wouldn't pay for it if I did. Use a piece of aluminum can wrapped around the worm if it bothers you.

 

[Vintage Engine Repairs]

Just use a small hammer on the large seal and be very careful to start it evenly.

I've never used any installation sleeve for the worm gear. Never knew such a thing existed and wouldn't pay for it if I did. Use a piece of aluminum can wrapped around the worm if it bothers you.

Wonderful, thanks very much for the advice. I’ll forgo the installation tool and just proceed with caution.

Warm regards,

 

[alexcagle]

Be wary, I once had the big seal on the pto side pop out after a few uses.
The leak is so large, the saw won't start at all. Nada.
There is rubber on the exterior on some variations of the seal, and lacquer thinner makes the rubber "slick", and eases installation. It evaporates very quickly.

 

[Vintage Engine Repairs]

Be wary, I once had the big seal on the pto side pop out after a few uses.
The leak is so large, the saw won't start at all. Nada.
There is rubber on the exterior on some variations of the seal, and lacquer thinner makes the rubber "slick", and eases installation. It evaporates very quickly.

Thanks for the advice and heads up!! I may pop in some dirko to seal it. It’s a super weird configuration, I’m surprised the worm gear and outer seal has enough friction to be air tight but it is!

 

[cbfarmall]

You should see the drum and seals on a Remington Bantam series saw.

Chris B.

 

[Vintage Engine Repairs]

You should see the drum and seals on a Remington Bantam series saw.

Chris B.

I’ll google it!

 

[Vintage Engine Repairs]

Hi gents,
Light bulb moment - the installation sleeve is so that the threads of the crank don’t damage the worm gear seal!
I have a sleeve for my ms 260, but when it passes the threads and butts against the step on the crank after the threads the sleeve is slightly wider than the crank, I don’t want to stretch this seal. I’m not sure how much give these seals have?
crank diameter is 14mm and the sleeve that I use in my ms 260 is 15mm where they meet.


Any advice would be great

 

[trappermike]

As for the seal on the worm gear,just grease it,oil the crank and push it in. Now you must replace the rubber ring around the oil pump and the small o-ring in it,or the saw will suck chain oil into the motor and smoke heavy. I normally knew when these were worn when I tried to pull over the motor and it seemed to have incredible compression! It was chain oil filling the cylinder. Great smoke show when they start though...

 

[cbfarmall]

Put a wrap of electrical tape on the threads and some grease on that. Don't make it more difficult or expensive than it needs to be.