68' 427 ps problem, need help!
Team Owner
Joined: Jul 1999
Posts: 26,545
Likes: 46
From: Huntersville NC
Just checked mine. Looks like I have a 2 groove pulley on my alt. Not factory, right? 
but it achieves the goal of putting the belt a little farther out to line up with the outer p/s pump pulley. (groove #3 in the AIM diagram)
but it achieves the goal of putting the belt a little farther out to line up with the outer p/s pump pulley. (groove #3 in the AIM diagram)
Le Mans Master
Joined: Dec 2003
Posts: 5,381
Likes: 415
From: N J
I just went through that mess last month with my 68 BB. Turns out I had a very similar looking cast 2 groove pulley for the pump but it was wrong. Didnt realize it till a friend noiticed it. Hers a few pics. Also I purchased the later design alternator outer brace gm used for 74 big blocks, I feel it puts less stress on the top alternator brace going into the head, instead it mounts to the waterpump. My friends 66 kept popping that bolt, turns out he wasnt alone, we posted it years ago and lots of guys have had that same bolt snap. See pic. Thanks and good luck.
Last edited by John 65; May 17, 2010 at 10:23 PM.
Melting Slicks
Joined: May 2009
Posts: 3,079
Likes: 314
2024 C3 of the Year Finalist - Unmodified
John
I know what you mean about that bolt. When I bought my car, that bolt was broken off inside the head. Ended up breaking off a small drill bit as well as a large easy out. Had a special fixture made so that I could drill out most of the remnants with some very expensive bits and re-tap the hole. When I had the engine rebuilt, I had them clean out the hole some more and put in a heli-coil. I think I am going to take your advice and find that '74 revised outer brace. An ounce of prevention is worth more than a pound of cure.
I know what you mean about that bolt. When I bought my car, that bolt was broken off inside the head. Ended up breaking off a small drill bit as well as a large easy out. Had a special fixture made so that I could drill out most of the remnants with some very expensive bits and re-tap the hole. When I had the engine rebuilt, I had them clean out the hole some more and put in a heli-coil. I think I am going to take your advice and find that '74 revised outer brace. An ounce of prevention is worth more than a pound of cure.
Thread Starter
Drifting
Joined: Oct 2008
Posts: 1,369
Likes: 12
From: wichita kansas
John 65, thanks for the pics, very helpful....i ordered the correct alt pulley from CC, and that should take care of my pulley alignment issues!
Faster Rat....let me know if you find that later style brace, i think i would be interested in going that route also! Rick
Faster Rat....let me know if you find that later style brace, i think i would be interested in going that route also! Rick
Le Mans Master
Joined: Dec 2003
Posts: 5,381
Likes: 415
From: N J
Hey it took a few trips to the local FLAPS but I finally got what I feel is the correct belt on there for the inner most grooves of the wp and crank pulley. Large pic for belt numbers. I got these 3 belts from napa. It wasnt fun putting the inside belt on 
but it finally went. Hope this helps others !
but it finally went. Hope this helps others !
Le Mans Master
Joined: Dec 2003
Posts: 5,381
Likes: 415
From: N J
Thanks Rick, According to the fellow that sold it to me he said its a 34 inch. Thats my old bike from back in the day...it was a 1975 H2 750, 3 cylinder 2 stroker. Peolple nicknamed it "the widowmaker" back then. ahhh...... the good ole days !
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Melting Slicks
Joined: May 2009
Posts: 3,079
Likes: 314
2024 C3 of the Year Finalist - Unmodified
I believe the belt from the crank pulley to the water pump pulley is 32" or at least mine says GM 9433716 EW GOODYEAR 440X3200. This is the same belt that I was running to the alternator from the power steering pump, but it was too long. I've since gone to a 31" there, which is almost too tight. It was a bear getting on...had to take the alternator off the brackets and work that way. It is better than having the alternator adjustment all the way out to the end.
I don't see the problem putting that CS/WP belt on. You need to take the WP pulley off, place the belt in the rear grooves of both pulleys and then slide the WP pulley over the protruding center pin on the pump flange. Then wiggle it 'til you can get the bolts in. Sure it is tight but without a tensioner, you don't want it loose.
I don't see the problem putting that CS/WP belt on. You need to take the WP pulley off, place the belt in the rear grooves of both pulleys and then slide the WP pulley over the protruding center pin on the pump flange. Then wiggle it 'til you can get the bolts in. Sure it is tight but without a tensioner, you don't want it loose.
Thread Starter
Drifting
Joined: Oct 2008
Posts: 1,369
Likes: 12
From: wichita kansas
John65, those old kaws 3cylinder 2-strokes were screamers! i remember them well! "widowmaker" sounds about right!
Faster Rat.....i put a new belt on the crank/water pump tonight.....this is a REAL JOB! to get a belt that is tight enough when installed, it means that there is a LOT of tension on the pulley, and it is not easy to get the water pump pulley back in place and line up the bolts for the fan. TRUST ME! (i suspect that very few of these belts were replaced on original cars if the first belt failed) Rick
Faster Rat.....i put a new belt on the crank/water pump tonight.....this is a REAL JOB! to get a belt that is tight enough when installed, it means that there is a LOT of tension on the pulley, and it is not easy to get the water pump pulley back in place and line up the bolts for the fan. TRUST ME! (i suspect that very few of these belts were replaced on original cars if the first belt failed) Rick
Race Director
Joined: May 2006
Posts: 16,528
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From: Dayton, Ohio
Faster Rat.....i put a new belt on the crank/water pump tonight.....this is a REAL JOB! to get a belt that is tight enough when installed, it means that there is a LOT of tension on the pulley, and it is not easy to get the water pump pulley back in place and line up the bolts for the fan. TRUST ME! (i suspect that very few of these belts were replaced on original cars if the first belt failed) Rick
Race Director
Joined: Dec 1999
Posts: 11,094
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From: Sierra Foothills CA
