You really can’t confirm if the case gasket is leaking as you can’t get in between there.
Once I get it together, before I reassemble anything else, I’ll do another pressure/vacuum test. If it’s good then I’ll put it back together all the way.
Pioneer 620 - Won't rev up clean to full throttle
- Thread starter cdahl383
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Once I get it together, before I reassemble anything else, I’ll do another pressure/vacuum test. If it’s good then I’ll put it back together all the way.
You can't see it from the bottom and front of the saw? My memory must be fuzzy here.
Not really. You can kind of see in there but not very good. The seal is hard to see too. You cant see at all on the right side by the gas tank, no way to really see in there.
Got the crankcase halves back together today. Put some oil on the crankshaft and the recessed area where the bearing fits. Also put some on the bearing itself.
Put some motoseal on the mating surfaces and slid the gasket in place. Fit the case half over the crankshaft and slid the crank seal slowly over the shaft. Got that seated good and then tapped the case half on with a wood block and hammer. Got it seated good and once the studs stuck through the case I put the nuts on and tightened it in a crisscross pattern. Got it tightened down pretty good.
Had to tap the crankshaft a few times to free it up. It spins nice and free now.
Brought the saw inside so the sealant could cure at room temperature. It’ll get down to 20-30 degrees at night out in the garage.
The gasket sealant package said to let it cure for 24 hours. I’ll wait to do a pressure test until tomorrow or Wednesday.
Hope it sealed up!
Put some motoseal on the mating surfaces and slid the gasket in place. Fit the case half over the crankshaft and slid the crank seal slowly over the shaft. Got that seated good and then tapped the case half on with a wood block and hammer. Got it seated good and once the studs stuck through the case I put the nuts on and tightened it in a crisscross pattern. Got it tightened down pretty good.
Had to tap the crankshaft a few times to free it up. It spins nice and free now.
Brought the saw inside so the sealant could cure at room temperature. It’ll get down to 20-30 degrees at night out in the garage.
The gasket sealant package said to let it cure for 24 hours. I’ll wait to do a pressure test until tomorrow or Wednesday.
Hope it sealed up!
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Ran another pressure/vacuum test on the saw today. Waited 48 hours for the Motoseal to cure at room temp, figured that would be good enough.
I was able to actually pump the crankcase up to 7-8psi but it did leak down slowly. The flywheel side seems to be fine, no issues there that I could tell. However, the clutch side seal now leaks. I think previously, the flywheel side leak was so bad that all the air just rushed out of that leak and there wasn't enough pressure to push out any bubbles on the clutch side. Either that or from shifting the crankshaft around slightly it tore/ruptured the old seal. Either way, that seal is bad, so I'll have to replace that one before I put the saw back together.
I looked online for a bit and found some different approaches to remove and replace that seal. I'm not a big fan of drilling into the seal and putting a screw in there, though I could see how that could work. I'm just afraid I'll end up going through the seal and into the main bearing.
I found a couple videos online where guys use a little screwdriver looking puller that slides between the crankshaft and seal and pulls up on the inner lip of the seal. Then you tighten the adjustment on the handle of the screwdriver and sort of use it as a fulcrum/lever to lift the deal out without damaging the crankshaft or recessed area the seal sits in. Of course I don't have one of those, so I'll have to buy/order one if I go that route.
I've seen other threads where guys modify a flathead screwdriver to have a little hook on the end and then slide that under the seal lip and use a socket slipped on the screwdriver shaft as a slide hammer to knock it out that way.
Any tips on how to remove this seal and install the new one without damaging the crankshaft or bearings? What method has worked best for you guys? This is my first time doing a seal like this one (the flywheel side one was different than this one).
Here's a quick video of the clutch side seal failing the pressure test...
I was able to actually pump the crankcase up to 7-8psi but it did leak down slowly. The flywheel side seems to be fine, no issues there that I could tell. However, the clutch side seal now leaks. I think previously, the flywheel side leak was so bad that all the air just rushed out of that leak and there wasn't enough pressure to push out any bubbles on the clutch side. Either that or from shifting the crankshaft around slightly it tore/ruptured the old seal. Either way, that seal is bad, so I'll have to replace that one before I put the saw back together.
I looked online for a bit and found some different approaches to remove and replace that seal. I'm not a big fan of drilling into the seal and putting a screw in there, though I could see how that could work. I'm just afraid I'll end up going through the seal and into the main bearing.
I found a couple videos online where guys use a little screwdriver looking puller that slides between the crankshaft and seal and pulls up on the inner lip of the seal. Then you tighten the adjustment on the handle of the screwdriver and sort of use it as a fulcrum/lever to lift the deal out without damaging the crankshaft or recessed area the seal sits in. Of course I don't have one of those, so I'll have to buy/order one if I go that route.
I've seen other threads where guys modify a flathead screwdriver to have a little hook on the end and then slide that under the seal lip and use a socket slipped on the screwdriver shaft as a slide hammer to knock it out that way.
Any tips on how to remove this seal and install the new one without damaging the crankshaft or bearings? What method has worked best for you guys? This is my first time doing a seal like this one (the flywheel side one was different than this one).
Here's a quick video of the clutch side seal failing the pressure test...
Attachments
Is that just a custom made ground down screwdriver?
Won't hurt. Most of it will rub off. Regarding, the seal tool, I've ground a few small screwdrivers down to make them. Also, it helps to knock the seal in slightly to dislodge it. They can get really stuck after 60 years or so.
