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5773
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Athens, GA
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4298th
Edited Date/Time
3/5/2015 4:02am
I'm in process of building my first motor from having it completely disassembled and am running into a newb mistake and snafu. When installing the crankshaft, I inserted in the flywheel side first (I learned later that I should have gone in the clutch side first).
The cases came together relatively easily. The input shaft spins freely. When I tighted down the drive gear nut (right side of crank), the crankshaft had a little resistance. I grabbed my feeler gauges and got a quick measurement between the crank weights and cases (as looking down from above).
.034"
.046"
The measurements hold true at 12, 3, 6, and 9 o'clock, so the crank is still true. I'm thinking I didn't get the clutch side main bearing seated well enough, and that's causing the crank to lightly bind when I tighten it down on that side.
I tried lightly tapping on each crank end with a rubber dead blow to see if the resistance would lesson, but no luck. I re-checked for trueness and I'm still good there.
Will I have to split cases to finish seating the right side crank bearing? If so will I need to go ahead and get 2 new crank seals in case I bugger the new ones installed in the motor now? Is there a way of pulling that bearing back in its seat without splitting cases (or damaging them)?
The cases came together relatively easily. The input shaft spins freely. When I tighted down the drive gear nut (right side of crank), the crankshaft had a little resistance. I grabbed my feeler gauges and got a quick measurement between the crank weights and cases (as looking down from above).
.034"
.046"
The measurements hold true at 12, 3, 6, and 9 o'clock, so the crank is still true. I'm thinking I didn't get the clutch side main bearing seated well enough, and that's causing the crank to lightly bind when I tighten it down on that side.
I tried lightly tapping on each crank end with a rubber dead blow to see if the resistance would lesson, but no luck. I re-checked for trueness and I'm still good there.
Will I have to split cases to finish seating the right side crank bearing? If so will I need to go ahead and get 2 new crank seals in case I bugger the new ones installed in the motor now? Is there a way of pulling that bearing back in its seat without splitting cases (or damaging them)?
The Shop
If I have a bigger gap on the clutch side of the crank, would I need to bump the flywheel or clutch side? Or does it matter and am I just bumping it to try and get it to settle without moving it one way or another?
Seems like the right/clutch side is the problem.. if I get the light binding when I tighten down the main drive gear, seems like the crank is bumping up against the bearing a little. Pulling that right side crank bearing in the case .010 seems like it should get the job done (?) Please correct if I am off base.
You first need to take the cases back apart. lay a machinists level (or something you know is 99% flat) and make sure the bearings are completely seated with the surface of the case. I think you will find that one of the bearings is sticking up slightly.
Re-assemble. If you want to do the job right, you need to invest in a crank wedge so you can properly space the crank gaps.
That being said, I tend to agree with your assessment above. Either the right side main bearing is not fully seated in the cases, or the crank just needs to be pulled to the right a little.
Almost every time I've put cases back together I first pulled the crank into the right case and then pulled it into the left case. If I "over-pulled" it just a bit when bottoming the cases together it would shift the crank slightly to the left. I would then have to put the puller back on the right side and re-seat it to the right.
So, I think the right answer is to put a crank puller on the right and pull it back that way. I think that's a better idea than whacking on the left end with a hammer.
Pit Row
Been there done that.
Mucho, mucho gracias.
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