C1 Generator ID
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From: Lake Norman NC
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C1 Generator ID
I'm new to generators and can't tell what I have in my 61; it works well enough but the pulley wheel has a roughly 3 1/4" diameter. I've read somewhere it should be around 3 5/8". The RPMs are correct with the low HP tachometer. Any ideas?
Thanks
Thanks
Melting Slicks
Joined: Oct 2004
Posts: 2,730
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From: Lakeland FL
You want EXACTLY half the effective diameter of the crank pulley, and it should be 3-3/8 or so. Otherwise, rpm will be overstated accordingly.
Stock gen turns double the speed of the engine, and then the gear box in back of the gen cuts it back in half again, so cable is turning engine speed.
I went 20 something years with rpm not matching mph until I figured out a rebuilder had installed a different pulley on my unit. Went back to the shop (which was going out of the electrical rebuild business and throwing everything out) and found what appeared to be the correct size pulley, possibly even my original pulley.
Stock gen turns double the speed of the engine, and then the gear box in back of the gen cuts it back in half again, so cable is turning engine speed.
I went 20 something years with rpm not matching mph until I figured out a rebuilder had installed a different pulley on my unit. Went back to the shop (which was going out of the electrical rebuild business and throwing everything out) and found what appeared to be the correct size pulley, possibly even my original pulley.
Last edited by toms silver 60; Dec 8, 2013 at 01:11 PM.
Safety Car
Joined: Nov 2007
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From: East Central Florida
We had a long discussion here which has all of the info....
http://forums.corvetteforum.com/c1-a...ment-help.html
post #18 has a pdf file at the bottom with good details of differences too.
What's the Delco metal tag have stamped in it? A 61 would be 1112043, and a date code.
Your pics are telling me you have a passenger car generator front frame(ribbed around periphery), a non-61 pulley(no 1/4" space between pulley & fan, I think?). Pulley is apx 3 5/8" OD.
The end frame pics in the thread above will tell you what to look for. I suspect its a pass car also.
FYI, the drive belt is too long as you have no adjustment left, and someone stripped the brace attach bolt threads in the front frame and used a bolt/nut(reversed orientation). The correct 5/16" bolt, w/washers goes through the brace from back to front then threads into the frame. It also looks like the tach drive housing mount bolts are 3/8" diam(9/16" hex), s/b 5/16" diam, but could be a optical illusion in the pics.
Not trying to be critical, just informative.
Rich
http://forums.corvetteforum.com/c1-a...ment-help.html
post #18 has a pdf file at the bottom with good details of differences too.
What's the Delco metal tag have stamped in it? A 61 would be 1112043, and a date code.
Your pics are telling me you have a passenger car generator front frame(ribbed around periphery), a non-61 pulley(no 1/4" space between pulley & fan, I think?). Pulley is apx 3 5/8" OD.
The end frame pics in the thread above will tell you what to look for. I suspect its a pass car also.
FYI, the drive belt is too long as you have no adjustment left, and someone stripped the brace attach bolt threads in the front frame and used a bolt/nut(reversed orientation). The correct 5/16" bolt, w/washers goes through the brace from back to front then threads into the frame. It also looks like the tach drive housing mount bolts are 3/8" diam(9/16" hex), s/b 5/16" diam, but could be a optical illusion in the pics.
Not trying to be critical, just informative.
Rich
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Pro
Joined: Mar 2013
Posts: 606
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From: Lake Norman NC
2020 C1 of the Year Finalist - Unmodified
Corvette of the Year Finalist 2018
2017 C1 of Year Finalist
2015 C1 of Year Finalist
The metal tag says "Unit Parts Co (UP) remanufacturers". It looks to be quite old itself.
Thanks for the input everyone; it looks like I have another project to delve into..
Thanks for the input everyone; it looks like I have another project to delve into..
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From: Mustang OK
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What year/engine option/generator used a 4in pulley?
