1965 L79 Idler Pulley?

[Ronald B.]

I am restoring a 1965 Corvette roadster with an L79 engine and no power steering or air conditioning. The engine currently has two fan belts and an idler pulley like the L76 and L84 versions. (However, I am uncertain whether this setup is original.) According to the 6th edition of the 1965 NCRS Judging manual, "It is doubtful that the L79 engine was equipped with an idler assembly. Research is ingoing."

Is there a definitive answer to this question? How do the NCRS judges score this feature when the manual is uncertain?

At this point, I can easily leave off the idler and use a captured belt between the crank pulley and water pump pulley. A similar arrangement is shown on page 359 of Noland Adams' restoration guide for a 1966 L79 Corvette. Is that how the judges expect this car to appear?

Finally, if I am to use a smaller belt without the idler pulley (it looks like about 33" long...), where would I find an NCRS acceptable belt?

RB

[Don H.]

Re: 1965 L79 Idler Pulley?

We expect to see it and we usually see it. Suggest you leave it there. More than likely it is original.

And,
welcome to the Tech Discussion Board.

[Timothy B.]

Re: 1965 L79 Idler Pulley?

Ronald,

The idler is supposed to be on the L79 engine in 1965. The forward belt runs crankshaft water pump and alternator, the belt closest to the engine runs crank water pump and uses the idler pulley.

[Andy C.]

Re: 1965 L79 Idler Pulley?

i just restored a 65 with a friend of mine who has owned the car since 1966. It was an L79 and had an idler pulley. It was original to the car.

[Ronald B.]

Re: 1965 L79 Idler Pulley?

Thanks to Don, Tim, and Andrew!

I will leave my idler in place for now. I wonder why the 1965 Judging Guide is so unclear about this?

RB

[Don H.]

Re: 1965 L79 Idler Pulley?

Ron
it's imperfect science. The JGs hit the nine ring in most cases, but not always.
Be glad your idler pulley is there and thankful to have it.

[Joe L.]

Re: 1965 L79 Idler Pulley?

Thanks to Don, Tim, and Andrew!

I will leave my idler in place for now. I wonder why the 1965 Judging Guide is so unclear about this?

RB

Ronald------


Look closely at the bearing/shaft assembly that's part of the idler pulley assembly. If there is an "ND" or "NDH" followed by a number, that would indicate an original bearing assembly. In that case, it's very likely that the idler pulley assembly is original to the car. It's, of course, not a certainty but it's very likely.

[Ronald B.]

Re: 1965 L79 Idler Pulley?

Joe,

Thanks for your input. I assume the ND would be for New Departure bearing or something like that.

I don't see any markings at all on my idler pulley...and I really didn't think it was original. I'm guessing the assembly was replaced at some time in the past fifty years.

What threw me off was the remark in the 1965 judging manual that said it was doubtful that the idler was used on the L79 engine in 1965. Now that I've gotten some feedback assuring me that it was used on this engine, I know how to proceed.

Thanks again,
Ron

[Joe L.]

Re: 1965 L79 Idler Pulley?

Joe,

Thanks for your input. I assume the ND would be for New Departure bearing or something like that.

I don't see any markings at all on my idler pulley...and I really didn't think it was original. I'm guessing the assembly was replaced at some time in the past fifty years.

What threw me off was the remark in the 1965 judging manual that said it was doubtful that the idler was used on the L79 engine in 1965. Now that I've gotten some feedback assuring me that it was used on this engine, I know how to proceed.

Thanks again,
Ron

Ron-----


Yes, "ND" denotes New Departure and "NDH" denotes New Departure-Hyatt.

The marking will not be found on the pulley or bracket sections of the assembly. If there, it will be found only on the either end of the bearing assembly which is pressed into the bracket.