'61 Harmonic Balancer Question

[Jack H.]

Re: '61 Harmonic Balancer Question

Balancer's with the 'woodpecker' holes on the outer ring are well known for having been factory original to low horse, '66-67 SB engines...

[David L.]

Re: '61 Harmonic Balancer Question

Balancer's with the 'woodpecker' holes on the outer ring are well known for having been factory original to low horse, '66-67 SB engines...

Jack,

I assume you are referring to the balancer with the stamped steel outer ring when you say " the 'woodpecker' holes on the outer ring". It is very possible that the balancer I found on the 60 Chevrolet 283 was a replacement as a lot can change in 31 years (1960 to 1991).
My 1966 & 1967 Chevrolet Parts Catalogs (Oct. 65 & Apr. 67) show GM # 3883956 as the balancer part number for "66 ALL w/nodular crankshaft (283)(1st design)" and described as "w/o pulley (6 1/4 O.D.)". GM # 3883956 does not appear in my 1965 Chevrolet Parts Catalog (May 1965) or any earlier parts catalogs. If you say the "woodpecker" balances were used on low HP 66-67 Chevrolets then I would say the GM part number is 3883956. GM # 3883956 was then replaced with GM # 3861970 in Nov. 1967.

Dave

[John H.]

Re: '61 Harmonic Balancer Question

My 1966 & 1967 Chevrolet Parts Catalogs (Oct. 65 & Apr. 67) show GM # 3883956 as the balancer part number for "66 ALL w/nodular crankshaft (283)(1st design)"

Dave -

As far as I know, no Corvette 283 engine was ever built with a nodular iron (cast) crankshaft; all of them were forged steel. The use of nodular cast iron crankshafts for some 283's started in 1965, long after Corvette 283 usage stopped in 1961.

[David L.]

Re: '61 Harmonic Balancer Question

Dave -

As far as I know, no Corvette 283 engine was ever built with a nodular iron (cast) crankshaft; all of them were forged steel. The use of nodular cast iron crankshafts for some 283's started in 1965, long after Corvette 283 usage stopped in 1961.

John,
I never stated that the 283 Corvette engine used a nodular crankshaft.
The term "ALL" when used in the Chevrolet parts catalog means all passenger cars EXCEPT for the Corvette. According to the 66 & 67 parts catalogs the 3883956 is to be used on all 1966 Chevrolet passenger cars (not the Corvette) with the 283 nodular crankshaft (1st design).
Dave

[Joe L.]

Re: '61 Harmonic Balancer Question

John,
I never stated that the 283 Corvette engine used a nodular crankshaft.
The term "ALL" when used in the Chevrolet parts catalog means all passenger cars EXCEPT for the Corvette. According to the 66 & 67 parts catalogs the 3883956 is to be used on all 1966 Chevrolet passenger cars (not the Corvette) with the 283 nodular crankshaft (1st design).
Dave

Dave------


I don't think that ANY 283, Corvette or otherwise, used a nodular iron crankshaft during the C1 period of 1955-62.

[Bill B.]

Re: '61 Harmonic Balancer Question

I was always under the impression that this is a picture of a 270, 290 & 315hp balancer.

Bill

1961 Black/Silver/Red Int. 283/315 FI
power windows. Frame off 65% completed.
1989 White/hard top/Grey Int. daily driver 167,000 miles

The problem with Liberalism is that eventually you run out of other people's money" - Margaret Thatcher

[Ray C.]

Re: '61 Harmonic Balancer Question

I was always under the impression that this is a picture of a 270, 290 & 315hp balancer.

Bill

1961 Black/Silver/Red Int. 283/315 FI
power windows. Frame off 65% completed.
1989 White/hard top/Grey Int. daily driver 167,000 miles

The problem with Liberalism is that eventually you run out of other people's money" - Margaret Thatcher

Hi! Bill

There should be no holes on the outside ring. I have been told that the balancer like the one pictured was used on the 348-CI engine. (I have never seen one) A vendor at Carlisle, I was looking for a HP balancer for my 61 FI project, told me that he has seen people thread, plug and then balance the 348 balancer to look like the High performance balancer. There is a vendor (seen the balancer in his booth at Carlisle) that has been modifying balancers for the high performance balancer and they look like your balancer.

Ray

[Joe L.]

Re: '61 Harmonic Balancer Question

Hi! Bill

There should be no holes on the outside ring. I have been told that the balancer like the one pictured was used on the 348-CI engine. (I have never seen one) A vendor at Carlisle, I was looking for a HP balancer for my 61 FI project, told me that he has seen people thread, plug and then balance the 348 balancer to look like the High performance balancer. There is a vendor (seen the balancer in his booth at Carlisle) that has been modifying balancers for the high performance balancer and they look like your balancer.

Ray

Ray------


The problem is that GM says that the balancers for 283's and 348's were the same. There was a part number for lower performance 283's + lower performance 348's and a part number for higher performance 283's + higher performance 348's.

After the late 60's, the GM #3896904 became the SERVICE balancer for all.

[Loren S.]

Re: '61 Harmonic Balancer Question

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=300506651474&viewitem=&sspagename=STRK%3AMEWAX%3AIT

[Joe L.]

Re: '61 Harmonic Balancer Question

http://cgi.ebay.com/ebaymotors/ws/eB...K%3AMEWAX%3AIT

Loren------


I wonder how he knows it's a GM #3764318?

[David L.]

Re: '61 Harmonic Balancer Question

Loren------


I wonder how he knows it's a GM #3764318?

GM # 3764318 is the balancer part number for 1959-1961 Corvettes w/H.L. cam, H.P. and was discontinued in November 1962 and replaced by the 3817684 balancer (1962-1965 models). The seller might be correct as I have never seen a balancer like this.

[Ray C.]

Re: '61 Harmonic Balancer Question

Hi! Joe

Thanks for the information about the HP balancer. The information that I posted was from vendors at Carlisle when I was on the hunt for a HP balancer . Is the balancer that Bill Berger pictured in his post the service replacement balancer? If not, would you know the application for this balancer.

Thanks for the correct information!
Ray

[Joe L.]

Re: '61 Harmonic Balancer Question

Hi! Joe

Thanks for the information about the HP balancer. The information that I posted was from vendors at Carlisle when I was on the hunt for a HP balancer . Is the balancer that Bill Berger pictured in his post the service replacement balancer? If not, would you know the application for this balancer.

Thanks for the correct information!
Ray

Ray-----


I do not know whether the balancer pictured started life as a PRODUCTION or SERVICE piece. I've never been able to figure out the "holes versus no holes" issue.

[Robert B.]

Re: '61 Harmonic Balancer Question

Guys,

For what its worth here is another couple shots of the 270 horse balancer I have for my engine. I agree with Ray & Loren that there were no holes on the outside ring. I believe my balancer is the same style as the one on eBay. Note that one of my pictures includes the picture shown in the technical information & judging manual page 74 for a quick comparison. My balancer was rebuilt by dampner docs before I bought it and the enamel is baked on pretty thick and I can't make out any numbers if there are any.

[David L.]

Re: '61 Harmonic Balancer Question

I am convinced that the 59-61 Corvette w/ H.L. cam, H.P. balancer (GM # 3764318) has been identified.