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Rebuilding...
It's an SN-89 VR4. I put everything back together with the shims that were in it and the backside of the impeller was scraping the housing. So I added shims to the impeller and got it spinning smoothly, but then reassembled and the rotational torque was way to low. So I added 1 shim behind the balls, still too loose. Added another and had to add all of the included impeller shims, now the back of the impeller hits the housing again. Do I need to call Craig for more impeller shims or am I doing something wrong?
Jesse
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The shims go under the RACE which pushes the balls closer to the shaft. This should not cause the impeller to touch the case because the impeller shaft is not moving the balls/race is. You will need shims to go under the impeller to get the correct distance of the impeller to the housing. Are you torquing the bolts to the case and making sure the case is flat and not sideways when your done.
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But, if you put more shims under the race to push the balls further away from the case, the inner race moves with the balls which in turn moves the back, flat, side of the impeller closer to the inside of the housing. Then the small black shims are placed between the inner race and the impeller to push the impeller away from the case and keep the inner race seated between the balls. The case is torqued and not "sideways" (which I interpreted as the cases not flush with eachother). Am I understanding the mechanics of the shims correctly? Once I tighten the impeller bolt down, the screw draws the impeller shaft to the impeller and the balls are what keep the impeller shaft from coming through. BTW no seals are in, but I don't think that matters.
Am I correct in thinking that I just need more impeller shaft shims to push out the impeller?
Jesse
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Sounds right, but how much shim have you used. Thickness of total shims. How many miles are on the Balls. I have never needed to much shim but I cause I am not sure what you have in total shim.
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I have a total of two thin shims (don't know final size) plus the thick concave metal washer behind the race and about 10 of the little black impeller shims installed (again, unsure of measured size). The balls are brand new. The race sticks out of the housing approx. 1/8-3/16".
HTH,
Jesse
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So right now how much torque does it take to rotate the front pulley shaft with it together ready to run?
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Rotates pretty much by hand. The torque wrench I used was fubar, but I could put my hand all the way up on the handle and turn it easily with a 3/8" ratchet.
Jesse
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If you don't have a torque wrench, then maybe this helps: I can turn the pulley by 1 hand but need some force to do it, this is with the blower instaled completely but less belt and oil.
Oh, and I am a regular Joe :D
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It takes a nice push to rotate if done correctly. It sounds like you need more pressure but you really need a in/lb torque wrench to be sure. Are you splitting the shims between the upper and lower race. Something is not correct since you need 10 shims behind the impeller.
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No, did not shim the upper race, both are behind the lower race...will the shims go behind the upper race? That might solve my problem.
Jesse
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My VR4 when new had them split. I would take my unit apart every winter to inspect it and my unit had them at both places like the factory split them.
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And yours was torqued to 40-44 in/lb with no seals, empty and lubed balls/races?
Jesse
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I always measured mine with the seals in and just lube on the parts but not filled. 52-54 in/lbs.
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So my problem was I was tightening the impeller before I tightened the case. Now I have two of the thicker shims in, the same ones that came out, and with seals in and everything lubed I'm turning 10 ft/lbs = 120 in/lbs lol. Going to try to take out one of the shims and reassemble and try again. Beginning to think if those were the shims in the old setup...it probably was too tight when I bought it and caused my premature failure.
Jese
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The shims might have been correct if it had old balls in it.