Tricky bearing removal

[Dadatwins]

My Stihl 440
popped last saturday while I was cutting some pine logs, thought I popped the clutch but after digging around inside I realized I had thrown the flywheel side crank bearing. Saw swallowed up and spit out the cage and a few ball bearings. Of course when I went to tap out the bad bearing the center came out with the rest of the ball bearings and left me with just the outer ring still locked in. No way to tap it out from the flywheel side, not willing to attempt a dremel cut, and I really have no welding knowledge, I tried this trick.

Steel wool the chrome ring, then I
placed a carriage bolt with some grease on the top inside the steel ring against the case. Filled up the cavity around the bolt with JB weld, let it dry overnight. Next day a few taps on the bolt from the flywheel side and out comes the bolt and the ring. Grease stopped any JB from setting up on the cast casing, wiped it clean and ready to reassemble. Thought it was a neat trick if anyone gets in a similiar jam without a welder. Pics show process #1 is bad bearing, #2 is bolt with JB weld set up, #3 is ring and bolt out of the case.
pic #1
http://arboristsite.com/attachment.php?attachmentid=30169&d=1137027830

 

[Husky nut]

nice...i always use a socket that fits just right and knock out the old one and knock in the new one

 

[Lewis Brander]

Bearing removal:

Hello datatwins. Great idea, will have to keep this idea in mind. Another trick you might have tried would be to take something like a lifter remover or something similar, insert it into the ball groove, expand the lifter remover into the groove and using the slide hammer on the lifter remover, remove the bearing outer half. I've done this to remove bushings and other items that were in a blind hole. Just another trick I've used. Take care. Lewis Brander.

 

[Dadatwins]

Thanks Lewis, I wandered around NAPA auto parts for 1/2 hour trying to figure something out and looking for an expandable tool that I could insert into the 'blind hole' but was drawing a blank, of course the guy behind the counter just wanted to know what model and year was the vehicle but that is for another thread.

 

[stihltech]

bearing

Just one question. Did it come out hard. If you just tapped it out, the case is shot. Needs to be heated to be removed from the case.

 

[Dadatwins]

I did heat it with a torch before tapping it, but not much. I was not sure how much heat the JB could handle. I used a brass rod and shot hammer, 2 raps and it came out. New bearing went in already, froze the bearing and heated the case, tapped it in and it looks solid.

 

[Marco]

When I have to remove a timken cup I weld a bead on the inside surface where the rollers run. When it cools, the race shrinks and falls out. Something this small you would want to get a talented welder with a wire feed.

 

[fishhuntcutwood]

Dude, nice trick. I never would have thought the JB would hold, but nicely done. I'll keep that one in mind, but I'm fortunate enough to have a bearing puller and pusher for every individual bearing I'll encounter in my job.

Jeff

 

[stihltech]

heat

Good to hear, put it back together and get some more work out of it.

 

[jokers]

Just one question. Did it come out hard. If you just tapped it out, the case is shot.

I`ve seen a couple of 044s that needed red Loctite to hold the bearings in the case and then were fine.

Russ

 

[stihltech]

loose

OK, my question. I have a few cranks that have clearance between the inner race of the bearing and the crank. No real sloppines, the bearing is no longer a press fit on the crank. Any body have a repair? Do they make an undersize bearing? I am willing to bet less than .005 would make it tight again.

Just not sure if I want to chance the locktite repair and have to stand behind it.

 

[Lakeside53]

OK, my question. I have a few cranks that have clearance between the inner race of the bearing and the crank. No real sloppines, the bearing is no longer a press fit on the crank. Any body have a repair? Do they make an undersize bearing? I am willing to bet less than .005 would make it tight again.

Just not sure if I want to chance the locktite repair and have to stand behind it.

No "undersized" bearings that are available of the shelf. I see the same thing on TS400 and 350 cranks now and then as concrete dust gets into everything.


Two possibilities?:
You can "knurl" (I think that's the right spelling) The crank bearing surface to slightly raise it... Common on electrical motor shaft repairs.

I'd try this first (I did on an E220). There are some great loctites specifically for "retaining" shaft and bearings. Degrease the crank and bearing, then apply Loctite 648. There are a few others that may work also, but this one is easily obtainable. If you ever want to get it off, you'll have to heat the entire crank/bearing to about 350F..