BB Fan Belts
Thread Starter
Drifting
Joined: Nov 2002
Posts: 1,691
Likes: 203
From: Loveland, CO
BB Fan Belts
I have an early 69', L71 that I am putting back together. There was a recent post regarding the crank/water pump fan belt for this combo. Does anyone know if the '69 L71 came with the idler pulley to tension this belt. Mine doesn't have one now, but I am not sure if it had been removed in the past. The AIM manual is not too much help. I got the 1.1X81.5 cm belt recommended here before, and that is the one I used on my '73 BB, but the '73 has the idler pulley to take up any slack.
Should I install the idler pulley, or get a slightly shorter belt and try to force it on? I know this is a pain to get on/line up the water pump bolt holes, and then they still alway appear too slack.
Should I install the idler pulley, or get a slightly shorter belt and try to force it on? I know this is a pain to get on/line up the water pump bolt holes, and then they still alway appear too slack.
Melting Slicks
Joined: May 2001
Posts: 2,131
Likes: 4
From: May help you? You can sure as hell try!
I think that idler was used only on AC cars. Since L71's didn't have AC you probably don't need the idler. Yes, that belt is a PIA to change. Do yourself a favor and make sure you buy the correct repro belt from Quanta, Paragon, etc. --not a "close" fit from Autozone etc.
I posted a thread last year asking the best way to change this belt. I took the pulley loose at the crank, left one bolt loose, put the belt on, and then swung the pulley around until I could get another bolt hole to line up. Sounds easier than it was because that belt is TIGHT. Another forum member recommended taking the water pump pulley loose and using a couple of threaded rods in place of two of the attaching bolts. This allows the pulleys and spacers to lay over but still keep everything aligned. Then put the belt in place, tighten nuts down on the threaded rod until the pulleys are close enough in position that you can tighten down two of the attaching bolts. Then remove the threaded rods and replace the other two bolts. I couldn't find threaded rod with the fine threads I needed to screw into the water pump flange but maybe you'll have better luck.
Good Luck on this one.
I posted a thread last year asking the best way to change this belt. I took the pulley loose at the crank, left one bolt loose, put the belt on, and then swung the pulley around until I could get another bolt hole to line up. Sounds easier than it was because that belt is TIGHT. Another forum member recommended taking the water pump pulley loose and using a couple of threaded rods in place of two of the attaching bolts. This allows the pulleys and spacers to lay over but still keep everything aligned. Then put the belt in place, tighten nuts down on the threaded rod until the pulleys are close enough in position that you can tighten down two of the attaching bolts. Then remove the threaded rods and replace the other two bolts. I couldn't find threaded rod with the fine threads I needed to screw into the water pump flange but maybe you'll have better luck.
Good Luck on this one.
Thread Starter
Drifting
Joined: Nov 2002
Posts: 1,691
Likes: 203
From: Loveland, CO
Hans, the NAPA number would be appreciated. If you still have the package, the length would help a lot. Was it a 81.5 cm?
Someone recently said they used the Kelly Springfield (11AV0815), 1,1X81,5 cm belt. The one I got from Auto Zone was a Duralast No. 15320, 1,1X81,5 cm, and also had the same number on it (11AV0815) as the Kelly Springfield mentioned above. I'm not sure why they use a comma instead of a decimal in the size designations, unless it is the foreign translation.
Someone recently said they used the Kelly Springfield (11AV0815), 1,1X81,5 cm belt. The one I got from Auto Zone was a Duralast No. 15320, 1,1X81,5 cm, and also had the same number on it (11AV0815) as the Kelly Springfield mentioned above. I'm not sure why they use a comma instead of a decimal in the size designations, unless it is the foreign translation.
Safety Car
Joined: Oct 1999
Posts: 4,101
Likes: 10
From: NorCal
Originally Posted by LemansBlue68
Do yourself a favor and make sure you buy the correct repro belt from Quanta, Paragon, etc. --not a "close" fit from Autozone etc.
Hans
Racer
Joined: May 2004
Posts: 445
Likes: 1
I found this post doing a search for a problem with my water pump belt. I also have the 11AV0815 number on my belt but it is a Goodyear number 15325 and it is really loose. Any one know what the correct replacement belt number should be?
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Le Mans Master
Joined: Dec 2003
Posts: 5,727
Likes: 38
From: Fremont CA
Check Dr Rebuild, he is an Expert on the 67-68-69 Tri-Power Vettes. The Dr Rebuild catalog will have the fan belts with the correct NCRS type GM part number on them. Paragon Corvette is also a good refrence but, Doc Rebuild collects these cars so I would check with him. Here is the link to Doctor Rebuild: http://www.docrebuild.com/dr-r-web/AAA-HOME.HTML
Senior Member since 1492
Joined: Aug 2000
Posts: 87,927
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From: Just because I'm paranoid doesn't mean people aren't out to get me...
St. Jude Donor '09
I used a 32 inch from AutoZone for a 70 BB WP-crank. The stock number ends in 32 which is the length on all the belts. I installed it similar to LeMansblue and found it pretty easy.
Thread Starter
Drifting
Joined: Nov 2002
Posts: 1,691
Likes: 203
From: Loveland, CO
The one I finally got to fit was a Kelly-Springfield No. 17325 (13AV0825), 1.3cm X 82.5cm. It is the slightly fatter belt which causes it to ride up higher in the pulley grooves, so the extra length is right for mine.
Burning Brakes
Joined: Feb 2004
Posts: 958
Likes: 1
From: In the Beautiful Shenandoah Valley of VA
Ralph,
Glad that you found one that works well. How much trouble was it to install? I've seen several methods and was just curious how you went about it. Also, how much slack was there once it was in place? Thanks.
Steve
Glad that you found one that works well. How much trouble was it to install? I've seen several methods and was just curious how you went about it. Also, how much slack was there once it was in place? Thanks.
Steve
Thread Starter
Drifting
Joined: Nov 2002
Posts: 1,691
Likes: 203
From: Loveland, CO
Steve, all the other belts listed above were way too tight or too loose. The last one mentioned above that I finally settled on was the only on that I felt comfortable with. I could get the water pump pulley on the snout of the water pump and just tapped the pulley home with a rubber hammer. The fit after seating the pulley is fairly tight, but I suspect it will loosen up with driving.
I really resisted paying the super high prices for a "correct" belt that all the normal vette suppliers wanted for a $3 belt.
I really resisted paying the super high prices for a "correct" belt that all the normal vette suppliers wanted for a $3 belt.
