How to Video: Crank seal replacment, Pressure testing, Vacuum testing

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Thanx for the info. I believe i may be needing one in the future.:givebeer:

If your a do it your selfer its almost impossible to repair a saw right without pressure and vac testing. As Brad said, he fooled with that saw for quite awhile switching carbs and such. He found the problem instantly with the pressure/vac tests. If a seal is found like the one he found that puller comes in very handy. Seals can be removed with tools as a simple screwdriver but care must be taken not to dent or damage the housing, damage the seal area of the case will result in the new seal leaking. Using the proper puller takes care of those issues altogether...
 
Thanks guys. I'm a DIY kind of guy. Yes, you can, and I did, get by without the proper puller for a long time. When I started getting into more saw work, it became apparent I needed these pullers. Yes they're pricey, VERY pricey. But you can see just how well they work.

Why did I wait so long to pressure test? I had some actual carb problems I was working on and just thought the fast idle was part of it. So I chased that tail first. It would have been quicker and easier in the long run to have just pressure tested it to begin with. But, I was not "rebuilding" this saw, just doing some mods for a friend, Nik. When I rebuild a saw, the seals come out automatically and are replaced. It's not worth trying to get around replacing them.

Anyway, I just thought I'd share what you can do in your garage with just a few tools. You can get by without the puller for a few saws, and the rest of the tools aren't that expensive.

Also, pressure and vaccum testing can have this auro around it that it's some difficult task requiring expensive and highly specialized tools. As you can see, it doesn't.

Go for it guys. Get them saws runnin' right and have some fun cutting wood this fall!
 
Brad,
Thanks for taking the time to film and edit that. A picture's worth a thousand words. Keep it up!
 
Hey Brad ( or Tommy ),

how do you know how far to press in the new seal and what are you measuring with ?

thanks, and thanks for posting the vids !
Angelo

No measurement needed. Just drive the seal slightly below the case edge and your go to go. Driving it in too deep , like into the bearing is a no no...
 
Not taking anything away from your video or how to, but I have found that you should rotate the crankshaft while pressure and vac testing...I have had one saw that would hold vacuum until you rotated the crank...Drove me nuts until I figured it out...But like the other have said great tutorial...
 
When you don't work in a shop, you sometimes don't know what you're missing. I guess I need to go do some shopping in my Stihl specialty tool catalog:)

Looks like you got it down pretty good without them. They come in nice but the way your doing it works and thats the main thing...
 
Hey Brad ( or Tommy ),

how do you know how far to press in the new seal and what are you measuring with ?

thanks, and thanks for posting the vids !
Angelo

The correct Stihl tool seats them to the correct depth for you, and keeps them nice and square. I don't have all those tools. It's as simple as taking note of the depth of the original and/or just making sure it's lower than what the flywheel will hit. You also have to make sure that you don't push the seal in too far such that the inner bearing race rubs on the inside of the seal. And do make sure to always lube the seal ID.
 
When you don't work in a shop, you sometimes don't know what you're missing. I guess I need to go do some shopping in my Stihl specialty tool catalog:)

Brad pick up 1128 850 4200 (it'll sub over to 5910 850 4200 ) makes life so much easier.

That one along with 1118 850 4200 and the Husky set for the 55 will cover 99% of everything you run into. :cheers:
 
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Not taking anything away from your video or how to, but I have found that you should rotate the crankshaft while pressure and vac testing...I have had one saw that would hold vacuum until you rotated the crank...Drove me nuts until I figured it out...But like the other have said great tutorial...

Another good point worth noting. I did do that outside of the video. It's as simple as slipping the flywheel onto the crank stub and rotating it a few times while still holding vacuum on the engine. You will see some fluctuation up and down as the piston compresses and creates vacuum through out it's stroke. But it should equalize again and remain where it started.
 
The 064 is one that comes to mind as being a little different than some. The flywheel side seal on that model has to be seated significantly deaper than normal due to stub on the flywheel sticking out farther.
 
Thanks Tom. I didn't even have to get out the impact scrench for this job;)

LOL, good one. You did good. I love these kinds of threads. I'm into selling and repairs, especailly when done correctly, you did real good and when you do a job well done I'll be the first to give you credit,:cheers::cheers:
 
The correct Stihl tool seats them to the correct depth for you, and keeps them nice and square. I don't have all those tools. It's as simple as taking note of the depth of the original and/or just making sure it's lower than what the flywheel will hit. You also have to make sure that you don't push the seal in too far such that the inner bearing race rubs on the inside of the seal. And do make sure to always lube the seal ID.

Thanks Brad. !
 

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