'63 340 SHP alt./fan belt

[Jim C.]

Re: '63 340 SHP alt./fan belt

Clem;

Bet you didn't do that with a reverse cooling Pontiac, did you?

I still suspect the alternator pulley because many an SHP 63 had theirs stolen or misappropriated and replaced by a standard L-75 piece.

Stu Fox

Stu,thanks for the input,but that pulley has been judged at least 5 times and while that's no guarantee I know it meets the description in the judging manual. I think the answer may lie in that fact that per the above posts loosing a belt was not an uncommon event at high rpm. Hence the idler pulley belt running the water pump.
At least that explanation sounds plausible.
I think I will put the new Quatra belt on, tension it tight and let it rip.
Will update this post on Saturday after a run to redline. Maybe the answer is a bulk order of fan belts.
Now that it's made Top Flight at the Nationals now it's time to have some fun.....matching numbers block not withstanding.( All the purists can now pile on after that comment)

[Duke W.]

Re: '63 340 SHP alt./fan belt

If there is no obvious misalignment sighting along the long run of the alternator belt, then it's probably okay.

Chevrolet went to the two belt system in '63 to solve thrown belt problems from earlier SHP/FI engines. My '63 has never thrown a belt.

Possible incorrect pulleies can always be an issue, but I wonder about these "reproduction belts". I think you're better off using a proper length commercial belt.

I prefer the Dynaflex line of belts from Dayco. They are actually a price leader as it seems the "premium" belts have "teeth" on the outside, which looks absolutely stupid.

You can find a proper belt by searching via the length that is listed in the AMA specs, but make sure you look are the proper length, because there are about three different ways to measure belt length.

Duke

[Clem Z.]

Re: '63 340 SHP alt./fan belt

Stu,thanks for the input,but that pulley has been judged at least 5 times and while that's no guarantee I know it meets the description in the judging manual. I think the answer may lie in that fact that per the above posts loosing a belt was not an uncommon event at high rpm. Hence the idler pulley belt running the water pump.
At least that explanation sounds plausible.
I think I will put the new Quatra belt on, tension it tight and let it rip.
Will update this post on Saturday after a run to redline. Maybe the answer is a bulk order of fan belts.
Now that it's made Top Flight at the Nationals now it's time to have some fun.....matching numbers block not withstanding.( All the purists can now pile on after that comment)

i have posted before if you have a riding mower take a look at the mower deck to see how they place belt guards to prevent the belts from coming off of the pullys when the belt is out of tension and build something like that.