Small Block Oil Pump Gasket who uses them. Been a while since I've done a SB but dont remember using one.

Nope.. I dont

Never used a gasket.. Just a thin smear of silicone.

I don't think I've ever assembled a SB without one
Most of the ones that came in the box with the new pumps where real thin gasket material, thin like writing paper

Ive always just used a very thin film of red anaerobic sealer

Built at least 10 engines without it. When tearing down virgin engines that were original 60s to 70s there was no gasket from the factory.

Throw those thin pieces of crap that they give you in the trash and bolt it on. Anytime I’ve taken one apart that had a gasket on it it’s always squeezed out and ripped anyway leading to more issues.

This X 1000

Use some fine paper on a flat surface (glass, etc.) and rub up the mating surfaces of the cap and pump while you're massaging and port matching to correct any burrs/rough machining.

This is all I do

The engine assembly was designed NOT to use any kind of fiber/paper type gasket. Although many gasket companies, as well as the typical Melling oil pump package, comes with a thin gasket, you are best to simply inspect the mating surfaces (oil pump and block/cap) so to assure flatness and no pitting or metal flash, then only use an anaerobic sealer (cures between metal-to-metal in the absence of air... DO NOT USE RTV silicone which requires air), then tighten to OE specs.

The very last thing you'd want is for some foreign material -- gasket material and/or RTV silicone -- to find its way into the oil pump or passage ways to then restrict the flow of oil.

Remember: RTV silicones are the most widely mis-used and improperly applied chemicals in the engine building industry. RTV should only be used at critical open-gap intersecting corners, such as the four corners of an Intake mfld or oil pan gasket assembly. Avoid spreading RTV all across a pre-made gasket, and never onto a rubber gasket.

I'm a former gasket engineer from a major company, wrote the instructions within their kits, taught hundreds of seminars, and was the lead person on their tech-line.

Thanks all...As I said I don't ever remember using one but its been 20 plus years since I've done a SB plus my memory is 20 plus years older as well so just needed a push.

On a side note while you are in there, check the clearance beween the counterweight & the underside of the pump body. & have the intergear in before you torque the 2 pump bolts (gives a dead on hex interface fit).

You guys have a lot of knowledge , I wish I would have asked that question before I put my junk back together. I have always used the gasket supplied with the pump. Never had a problem but this info is good to know.

I've always used a gasket. I've taken apart more than my fair share of engines that had never been touched and almost every one of them had a gasket. Never had a blowout.

There is no way two machined surfaces can seal without a gasket and seal correctly.

You didn't do anything wrong.

No gskt. When checking the counterweight flycut clearance, check the pump body as well. I had a Melling that was paper thin, and blew out.

And yet I find no part number for a gasket and no mention of one in service manuals. Last mention of a gasket between the pump and cap was in the fifties and it was a lathe cut O ring.

Never saw one in a factory engine. Plenty of stuff is put together with sealants only.

I also have never seen one in a factory engine and i have never used one or had any issues without one.

I’ve never taken one apart that had any type of gasket sealer on it either. Take the bolts out and it lifts right off.