69 Alt. Belt, Clear it up Joe Lucia, Thanks!

[Jamie F.]

I then looked back at an older 2004 post of yours where you say the 3940991 was the correct belt from production and the 3871257 was a non-correct service replacement.
For my application the dimensions of the 3940991 would seem to be perfect as it is wider and shorter.
What the definitive answer Joe?
Thanks!

[FONT='Tahoma','sans-serif']February 24th, 2009, 05:03 PM [/FONT]
[FONT='Verdana','sans-serif']Joe Lucia (12484) [/FONT]
[FONT='Verdana','sans-serif']Beyond Control Poster[/FONT]

[FONT='Verdana','sans-serif']Join Date: January 31st, 1988[/FONT]
[FONT='Verdana','sans-serif']Posts: 21,473 [/FONT]
[FONT='Verdana','sans-serif']Re: What's wrong with this pix....69 alt belt problem.[/FONT]
[FONT='Verdana','sans-serif']Quote:[/FONT]
[FONT='Verdana','sans-serif']Originally Posted by [/FONT][FONT='Verdana','sans-serif']Lynn Schwebach (42902)[/FONT]
[FONT='Verdana','sans-serif']Thanks, would greatly appreciate the help as Quanta did not seem to know of a problem. I purchased one of the alt belts from Paragon, but that shoudn't make a difference?? Lynn Schwebach[/FONT]
[FONT='Verdana','sans-serif']Lynn----


The alternator belt for your application should be GM #3871257 and be 3/8" X 54-3/4". Is that the part number on and dimension of the reproduction belt?[/FONT]
[FONT='Tahoma','sans-serif']September 28th, 2004, 08:21 PM [/FONT]
[FONT='Verdana','sans-serif']Joe Lucia (12484) [/FONT]
[FONT='Verdana','sans-serif']Beyond Control Poster[/FONT]

[FONT='Verdana','sans-serif']Join Date: January 31st, 1988[/FONT]
[FONT='Verdana','sans-serif']Posts: 21,473 [/FONT]
[FONT='Verdana','sans-serif']Re: L-71 Alternator Belt[/FONT]
[FONT='Verdana','sans-serif']Rich-----

Yes, GM #3940991 was the PRODUCTION alternator belt. This belt was a 15/32" X 53-1/2" belt. This is a real "oddball" size that you'll only obtain these days in a reproduction belt. For quite a few years, the belt that GM sold in SERVICE for this application was the GM #3871257. That belt was 3/8" X 54-3/4". It's not inconceivable that some of these MAY have found their way into PRODUCTION, too.[/FONT]

[Joe L.]

Re: 69 Alt. Belt, Clear it up Joe Lucia, Thanks!

I then looked back at an older 2004 post of yours where you say the 3940991 was the correct belt from production and the 3871257 was a non-correct service replacement.
For my application the dimensions of the 3940991 would seem to be perfect as it is wider and shorter.
What the definitive answer Joe?
Thanks!


[FONT='Tahoma','sans-serif']February 24th, 2009, 05:03 PM [/font]

[FONT='Verdana','sans-serif']Joe Lucia (12484) [/font]
[FONT='Verdana','sans-serif']Beyond Control Poster[/font]

[FONT='Verdana','sans-serif']Join Date: January 31st, 1988[/font]
[FONT='Verdana','sans-serif']Posts: 21,473 [/font]
[FONT='Verdana','sans-serif']Re: What's wrong with this pix....69 alt belt problem.[/font]
[FONT='Verdana','sans-serif']Quote:[/font]
[FONT='Verdana','sans-serif']Originally Posted by [/font][FONT='Verdana','sans-serif']Lynn Schwebach (42902)[/font]
[FONT='Verdana','sans-serif']Thanks, would greatly appreciate the help as Quanta did not seem to know of a problem. I purchased one of the alt belts from Paragon, but that shoudn't make a difference?? Lynn Schwebach[/font]
[FONT='Verdana','sans-serif']Lynn----


The alternator belt for your application should be GM #3871257 and be 3/8" X 54-3/4". Is that the part number on and dimension of the reproduction belt?[/font]
[FONT='Tahoma','sans-serif']September 28th, 2004, 08:21 PM [/font]
[FONT='Verdana','sans-serif']Joe Lucia (12484) [/font]
[FONT='Verdana','sans-serif']Beyond Control Poster[/font]

[FONT='Verdana','sans-serif']Join Date: January 31st, 1988[/font]
[FONT='Verdana','sans-serif']Posts: 21,473 [/font]
[FONT='Verdana','sans-serif']Re: L-71 Alternator Belt[/font]
[FONT='Verdana','sans-serif']Rich-----

Yes, GM #3940991 was the PRODUCTION alternator belt. This belt was a 15/32" X 53-1/2" belt. This is a real "oddball" size that you'll only obtain these days in a reproduction belt. For quite a few years, the belt that GM sold in SERVICE for this application was the GM #3871257. That belt was 3/8" X 54-3/4". It's not inconceivable that some of these MAY have found their way into PRODUCTION, too.[/font]

Jamie-----

The definitive answer is just as you have surmised. The 3940991 is the correct belt.

[Jamie F.]

Re: 69 Alt. Belt, Clear it up Joe Lucia, Thanks!

Thanks Joe!

[Jamie F.]

Re: 69 Alt. Belt, Clear it up Joe Lucia, Thanks!

Joe, Ironically or frustratingly, depending on how you look at it, Friday was drive your Vette to work day, which I did. And guess what? Yes, my Alternator belt shredded itself on the way home! Right after this posting... It had rolled before over as I mentioned so I guess it got stressed when that happened.
Luckily I had the 3940991 Quanta belt in the car. And I had a single 1/2"-9/16" line wrench I had just bought in the car. So I was on the side of the 605 Freeway and it was 90 degrees and I proceeded to try and put the other belt on. So just for the record there is not way you can put on the 3940991 over the alt pulley, just as Lynn posted it won't go. I tried for 15 minutes, and it was HOT. So I proceed to loosen up all the lower alternator bracket bolts and tilt the alternator to get the belt on. It work and I got it on. I don't think this is what the General intended so something is still not right on these belts.
As I was tightening the last bolt with my line wrench the Metro Highway Help truck pulled up, 40 minutes too late. But he did lend me a long screwdriver to pry the alt. tighter than I had done with my hand.
I see that Dr. Rebuilt lists a separate belt for '69 L68 w/o PS only, I'm trying to find out what that is.