72 valve cover grommets

[Jeff W.]

On a 72 small block, do you use the same grommet on both valve covers or do you use the square angled for the PVC and the round for the air cleaner?
Thanks for the help.
Jeff

[Joe L.]

Re: 72 valve cover grommets

On a 72 small block, do you use the same grommet on both valve covers or do you use the square angled for the PVC and the round for the air cleaner?
Thanks for the help.
Jeff

Jeff-----


It somewhat depends upon which small block we're talking about. However, assuming it's a steel valve cover base engine, I believe the "angled" style are used for both valve covers.

[Patrick H.]

Re: 72 valve cover grommets

Angled on left, round on right.

Patrick

[Jeff W.]

Re: 72 valve cover grommets

Patrick, thats what I have on there. Thanks for confirming.

[Joe L.]

Re: 72 valve cover grommets

Angled on left, round on right.

Patrick

Patrick-----


I used to think so, too. However, the AIM specifies a GM #3989350 for both sides, although the drawing depicts a round one on the right side and an "angled" one on the left (AIM drawings often contain anachronisms, though) . The GM #3989350 is a "squarish", "angled" grommet. It may well be that this was one of those unusual exceptions when the cars weren't built to specifications. However, considering that the round grommet was, apparently, not on the 1972 Corvette "Bill of Materials", I wonder how St. Louis ordered in the parts?

[Jeff W.]

Re: 72 valve cover grommets

Well since I am having it judged on Sat, I will print this, install the angled and bring the round!!! I have not seen anything that says the round one. Hopefully we can find out for sure, but your explanation sounds right to me.
Thanks
Jeff

[Patrick H.]

Re: 72 valve cover grommets

Original valve covers, and I sure didn't replace the grommets. They were in storage from 198X (or earlier) through 1997 and I saw them when they came out of storage. "What you see is what you get."

Patrick

[Robert C.]

Re: 72 valve cover grommets

I'll have to agree with patric, square on left (pvc), round on right(air cleaner)

[Joe L.]

Re: 72 valve cover grommets

Original valve covers, and I sure didn't replace the grommets. They were in storage from 198X (or earlier) through 1997 and I saw them when they came out of storage. "What you see is what you get."

Patrick

Patrick-----


I don't really think that yours are non-original. For one thing, if someone had replaced them at some point, why would they have replaced them with 2 different types? Of course, they could have just replaced the right side cover grommet and used a round one. But, it would seem unlikely that anyone would have replaced the right side grommet. So, I do expect that it was done this way at the factory. I just can't understand why they would have deviated from the specifications. There must have been a reason, though.

By the way, does the round grommet have a GM part number embossed on it anywhere? Some of these grommets do have an embossed GM part number. If so, I'd be interested to know what it is. If there, it will be tiny and, unfortunately, it may be on the portion beneath the cover.

Also, are both grommets "soft and pliable" or are they "hardened"?

[Patrick H.]

Re: 72 valve cover grommets

Patrick-----


I don't really think that yours are non-original. For one thing, if someone had replaced them at some point, why would they have replaced them with 2 different types? Of course, they could have just replaced the right side cover grommet and used a round one. But, it would seem unlikely that anyone would have replaced the right side grommet. So, I do expect that it was done this way at the factory. I just can't understand why they would have deviated from the specifications. There must have been a reason, though.

By the way, does the round grommet have a GM part number embossed on it anywhere? Some of these grommets do have an embossed GM part number. If so, I'd be interested to know what it is. If there, it will be tiny and, unfortunately, it may be on the portion beneath the cover.

Also, are both grommets "soft and pliable" or are they "hardened"?

Joe,

I know that they're quite hard, especially the round one.
The car isn't here for me to inspect the grommet for a number, but I could when I see the car next. Right now the car is in the middle of the back row of the picture below. The two cars closest to the camera are out of their "cocoons."

Patrick