Problem with new BDS 871 blower rotor issue
#11
[QUOTE=Panther;4405585]Slowly turning over the blower can you hear any sounds of rotor contact? Re
How do you time them?
Feeler gauge each side of the rotor and adjust to be equal?
Shim til lobes hit on one side, shim til they hit on the other, then split the difference?
How do you time them?
Feeler gauge each side of the rotor and adjust to be equal?
Shim til lobes hit on one side, shim til they hit on the other, then split the difference?
#12
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Joined: Jun 2013
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very hard to tell from those pictures. I dont know if you are thinking that rotors would put those marks in each rotor because they pass each other or not but if you look at panthers photo and you can see how the rotors mate up to one and other and if the rotors were scraping each other you would have two sets of marks in each rotor not one. From your picture you cant see marks in the concave portion of the rotor if you keep turning the blower do you eventually see marks on the inside of the rotor? If not it is definitely a rotor to case problem.
#13
You turn the rotors until they're at the closest contact and then, with feeler ribbons, you check the tolerance. I wanna say it was .003 - .005 clearance but don't quote me on that. If you are too loose it wont seal, too tight they'll swipe. Don Hampton gave me the tolerances when I did mine several years ago and I can't find them. Another thing that needs to be checked is the gear backlash.
#14
Here's a great step-by-step I found on the interweb... http://www.hotrod.com/how-to/engine/...n-8-17-blower/
If you're simply wanting to re-seal and re-bearing the blower, a lot of the clearance steps aren't necessary because nothing you're replacing will change the rotor timing unless you're installing new gears for example. I've done a half dozen now and the process was pretty easy in my opinion.
If you're simply wanting to re-seal and re-bearing the blower, a lot of the clearance steps aren't necessary because nothing you're replacing will change the rotor timing unless you're installing new gears for example. I've done a half dozen now and the process was pretty easy in my opinion.
#16
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very hard to tell from those pictures. I dont know if you are thinking that rotors would put those marks in each rotor because they pass each other or not but if you look at panthers photo and you can see how the rotors mate up to one and other and if the rotors were scraping each other you would have two sets of marks in each rotor not one. From your picture you cant see marks in the concave portion of the rotor if you keep turning the blower do you eventually see marks on the inside of the rotor? If not it is definitely a rotor to case problem.
#17
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I understand what you are saying and i am getting old and maybe all the scars from restripping them damn things is blocking my mind but to me the marks dont line up for which side of the teflon the marks are on. I was wondering if you could do a test for me if the motor is out of the boat. If it is i am sure you have spun the blower by hand and there are no tight spots while it is sitting on the bench. Try this sit it back on the motor and spin it by hand with no belt Then put the nuts on just finger tight and spin it and see if there are any tight spots then torque it down as you did when you put it on the motor and see if there are any tight spots Then let us know
#18
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I understand what you are saying and i am getting old and maybe all the scars from restripping them damn things is blocking my mind but to me the marks dont line up for which side of the teflon the marks are on. I was wondering if you could do a test for me if the motor is out of the boat. If it is i am sure you have spun the blower by hand and there are no tight spots while it is sitting on the bench. Try this sit it back on the motor and spin it by hand with no belt Then put the nuts on just finger tight and spin it and see if there are any tight spots then torque it down as you did when you put it on the motor and see if there are any tight spots Then let us know





