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General Forestry => Chainsaws => Topic started by: johnny newburgh on November 08, 2017, 08:26:59 pm

Title: stihl 031av can not remove crankshaft seal HELP
Post by: johnny newburgh on November 08, 2017, 08:26:59 pm
Working on Stihl 031 av could not get carburetor adjusted properly. Carburetor was rebuilt new fuel line. 150 psi compression. Picked up digital tachometer and could not get full rpms was getting 9500-10'000 but supposed to around 12'000. so then i pressure tested carburetor that was good then pressure and vacuum the case. Pressure was good  vacuum failed. so now I am trying to remove crankshaft seal on clutch side. Watched a couple videos where people drill small hole in side of seal and use wood screws to act as puller. when i try to do that there is not a big enough edge on seal to drill through. there seams to be 1/8 inch ring and there is plastic on side that just chipped away? when i looked at videos there is a nice flat section around seal to drill through. right now i am waiting for new seal to see what that looks like?
Title: Re: stihl 031av can not remove crankshaft seal HELP
Post by: HolmenTree on November 08, 2017, 09:07:05 pm
Welcome to the Forum Johnny, did you get the old seal out Ok?
Wait for your new parts someone hear can help you.
Title: Re: stihl 031av can not remove crankshaft seal HELP
Post by: johnny newburgh on November 08, 2017, 09:11:17 pm
Thank you no i did not get seal out yet was hoping when i look at new seal that would help. I have some photos to add to add to post but i can not figure out how to do that. when i hit edit post then on bottom i hit add photos and a era window pops up? also i hit my gallery but cant access my files?
Title: Re: stihl 031av can not remove crankshaft seal HELP
Post by: Al_Smith on November 09, 2017, 05:57:16 pm
One easy method to remove a seal is punch a tiny hole in the metal part and use a dry wall screw to remove it .Don't drill a hole because you risk getting shavings in the bearing .Be careful installing the new seal that you don't roll the lip .It will really leak then .Oil up the shaft and seal before hand with the installation
Title: Re: stihl 031av can not remove crankshaft seal HELP
Post by: johnny newburgh on November 09, 2017, 06:48:48 pm
Thank you good advice of just punching hole instead of drilling. I got the new seals today and the flywheel side has metal ring around it and clutch side looks to be rubber coated. but it gives me idea of the size of seal because  when i was trying to remove old one could not tell what piece was exactely the seal or case or crankshaft. I am trying to post picture to show how when i try to remove old seal has plastic around it that just chipped off. does not have nice metal ring to punch hole in?
Title: Re: stihl 031av can not remove crankshaft seal HELP
Post by: thecfarm on November 09, 2017, 09:13:44 pm
Hi Johhny,welcome to the forum.
You did the hard part.

 

 (http://www.forestryforum.com/gallery/albums/userpics/47523/IMG_2427.JPG?easyrotate_cache=1510271179)
Title: Re: stihl 031av can not remove crankshaft seal HELP
Post by: johnny newburgh on November 09, 2017, 09:39:06 pm
Hard part was posting picture haha. Got the seal out by picking around it collapsing a piece of it then prying it out. And as bad as that sounds i do not think i did any damage. After removal i can see that I was looking at two parts of the bearing race i think ? looks like crankshaft goes through in part of race then outer part of race against case and the seal is the middle. If you look at picture it is silver looking part up against crank and outside against case.
Title: Re: stihl 031av can not remove crankshaft seal HELP
Post by: johnny newburgh on November 09, 2017, 09:54:10 pm
after seal is out

 (http://www.forestryforum.com/gallery/albums/userpics/47523/IMG_2435.JPG?easyrotate_cache=1510282375)
Title: Re: stihl 031av can not remove crankshaft seal HELP
Post by: johnny newburgh on November 09, 2017, 09:58:37 pm
Also little confused here how does outer race seal to case? and how does crankshaft seal going through inner race? the seal is in the middle of the two races?
Title: Re: stihl 031av can not remove crankshaft seal HELP
Post by: limbwood on November 10, 2017, 10:36:47 am
on a lot of saws the seal is on the inside of bearing race, the bearing is pressed into case so it seals itself.
Title: Re: stihl 031av can not remove crankshaft seal HELP
Post by: old guy on November 10, 2017, 12:27:27 pm
That looks like a sealed bearing to me, not a seperate seal from the bearing.
Title: Re: stihl 031av can not remove crankshaft seal HELP
Post by: johnny newburgh on November 10, 2017, 04:50:10 pm
I bought replacement seals and they are separate from bearing but old one did look funky. The one on flywheel side looked normal with metal ring and should come out easier using screw trick. Another thing I tried to remove flywheel by hitting crankshaft with punch and i did not have any success and lightly hit threads on shaft. I would recommend for anyone to buy flywheel puller only 10-15 dollars.
Title: Re: stihl 031av can not remove crankshaft seal HELP
Post by: old guy on November 10, 2017, 09:06:44 pm
I always put the nut back on the shaft but not far enough so the shaft sticks out, then hit the nut with a hammer while prying under the flywheel with a screwdriver.
Title: Re: stihl 031av can not remove crankshaft seal HELP
Post by: johnny newburgh on November 10, 2017, 09:39:03 pm
Sounds good if you do not mess anything up. flywheel was on there pretty tight even with puller I had to apply a lot of force before breaking loose. So I got both seals out and installed new ones then I did pressure and vacuum test and all looks good. Started to reassemble now. One other note the seals on a smaller saw are pretty small  not much room to work. One seal Is about 3/4" and other 1" 1/4