Need Help with Grommet
 

Does anyone have a part number for the grommet that goes in the hole where the spark arrester goes. Its the bottom left hole in the picture.

Re: Need Help with Grommet
 

I think the flame arrestor takes the same grommet as the PCV. Looks like 3989347 for a 72.

Re: Need Help with Grommet
 

Thanks forte info. Putting 3989347 into Rock auto search it comes up with SMP GV20 and Dorman 42323 which I have but was having a toughtime getting it into the hole. Are these normally super tight when getting installed.

Re: Need Help with Grommet
 

If you measure the ID of the hole in the valve cover and the OD of what you are sticking in it. You can find a universal grommet on Summit. Or post the dimensions and I'll look for you...

Re: Need Help with Grommet
 

I meant to add. Yes, they are usually tight, use lubricant. Silicon grease or Dielectric grease...

Re: Need Help with Grommet
 

i have them here,just installed 2 in my 72 big block valve covers,same grommet for the flame arrestor and pcv.i imagine a small block is the same grommet.they push in a little tight,i wet mine in the groove and helped them in carefully with a tiny screwdriver.

Re: Need Help with Grommet
 

Thanks everyone. Went and looked on engine in garage and yes I have the right ones and will just need to need to lube and work em to get them installed.

Re: Need Help with Grommet
 

Did you get them at a GM dealer in Canada or get them in from USA.

Re: Need Help with Grommet
 

I think I heated mine up with a blow drier and they popped right in. Whatever works.

Re: Need Help with Grommet
 

I need a couple of those what is the part number on that bag.

Thanks
Mark

Re: Need Help with Grommet
 

Part Number is 3989347 and I just got some in from Rock Auto

Re: Need Help with Grommet
 

Thank you for the number and to check rock auto.

Re: Need Help with Grommet
 

I bought the Doorman 42323 grommets for the '70 SBC valve covers I'm working on. The inside diameter of the hole in the valve cover is 0.930". The outside diameter of the 42323 grommet is 1.25".

Are you guys actually getting this grommet to fit?

Re: Need Help with Grommet
 

I believe Dorman 42052 is the grommet that works with the spark arrestor. EDIT: The PCV and spark arrestor grommets have the same I.D. (I checked mine). Some PCV grommets are angled, whereas this spark arrestor grommet is straight.

https://www.dormanproducts.com/p-260...met&origin=YMM

Re: Need Help with Grommet
 

Yes that is what I found also. I went and visited with an old timer at the parts counter at the Chevy dealer in Plano TX. He ordered the breather grommet GM# 14091870 for me, and said the PCV uses the same grommet, or if I wanted to use the slanted PCV grommet from later year models it is GM# 3989350. He also sold me the later model years PCV valve with the right angle hose connection. I like that setup best with the slanted grommet and right angle PCV valve. I can use a plain hose and don't need the one that is molded to bend, and the hose doesn't stick up, it just lays flat. There are Dorman equivalents and Dorman grommet seems to me to be softer rubber and easier to install. I replaced the breather grommet with a Dorman after I wore out the GM one by taking the air cleaner spacer off a couple of times too many. This is for 1969 SBC 350 engine.

Breather/flame arrester grommet GM# 14091870 Dorman 42052
PCV valve slanted grommet GM# 3989350 Dorman 42062
PCV valve (right angle elbow type) GM# 6487779

Re: Need Help with Grommet
 

I usually add a drop of oil to the base and fold it like a Pac Man to get it in....

Re: Need Help with Grommet
 

Thanks for the responses to my question. I need to ask for clarification, though. Those Doorman grommets have an outside diameter that is more than a quarter inch larger than the hole it is meant to fit into.

For those with the approximately 1.2" outside diameter grommets fitting them into a 0.9" hole? That's 0.30" which appears to be quite a large difference. I'm not sure, though, hence the questions. I'll cram it in there if it's meant to be, just doesn't seem to be right.

Re: Need Help with Grommet
 

You can get these at a Auto Zone near you. The Proform part number is the same as the Acdelco number

https://www.autozone.com/engine/valv...set/751050_0_0

Re: Need Help with Grommet
 

I also had a hard time finding this grommet for my 1969 307 . NAPA 630-1038 worked for me . HTH

Re: Need Help with Grommet
 

Yes, cram it in there and it will expand back to the pre-cramming size once the metal is in the groove. Then insert PCV valve or flame arrester or breather tube.

Re: Need Help with Grommet
 

Thanks everyone. I'll get 'em crammed in there.

Re: Need Help with Grommet
 

...or so I thought I would get 'em in there.

I 'Pac Man'ed the grommet to no avail. Hard to see in the photo but the side of the grommet opposite my thumb is in the valve cover hole and right at the 'Pac Man'ed part of the grommet is the side of the valve cover hole.

The overhead view with the grommet over the valve cover hole shows the inside diameter of the grommet in line with the valve cover hole on the right side. That's the inside of the grommet hole lined up with the valve cover hole. It's supposed to be the outside of the grommet groove in that hole...much grommet overlapping the valve cover. You can see the left side of the valve cover hole along with the amount of grommet overlap.

There's no way on God's green Earth that grommet is getting in that hole AND returning to a useful round shape.

So, I will find the proper grommet for this application and let you know.

Re: Need Help with Grommet
 

What is the part number of your grommet?

Re: Need Help with Grommet
 

These are Doorman 42323 from Rock Auto.

Re: Need Help with Grommet
 

When I search online that part appears to be for 8 cylinder big block engines and 6 cylinder engines, not for small block 8 cylinder. Try the part numbers I gave in post 15, your local parts store or Chevrolet dealership if you have one nearby should be able to get them for you.