Throttle body shaft leak 911sc

[GTT]

So I’m troubling shooting a rough running problem after finishing a top end rebuild, and just dropped the motor again today so I could do a more thorough smoke test and see the backside of the intake system. Good news is there were no air leaks in my airbox or the usual suspect areas. However I had a pretty decent leak coming out of the throttle body shaft on the side where the WOT switch is. Anyone know if there are o-rings or something that can be replaced on that shaft? I can’t find anything in the service manual and it looks like in the parts manual there’s nothing but the complete throttle body - not any replacement parts for the throttle body itself.

‘82 SC Targa

[GTT]

In case anyone is wondering, yes there is a seal on each side of the throttle body shaft. I disassembled mine tonight so now the question is where can I get replacements seals? I thought about using a similar sized o-ring but the seals are flat around the outside, not round like a o-ring would be.

[A930Rocket]

Have you done a Google search for the flat O-rings*? Maybe McMaster has them?

As a workaround, maybe you could use a round O-ring? Maybe if it’s big enough, it would flatten over time.?

*I don’t know the technical name for them.

[GTT]

I’ve got a kit of various size o-rings so that’s my fallback plan. McMaster is a good idea. I’ll check.

[A930Rocket]

Flat Ring Seals

https://www.mcmaster.com/flat-ring-seals/o-rings-2~/

But I don’t see gas or fuel listed as use.

“For gas use, flat O-rings are often made from Nitrile (NBR), Viton® (FKM), or PTFE due to their chemical resistance and durability, though the specific material depends on the type of gas and operating conditions. Nitrile is good for general-purpose fuel systems, while Viton is better for high temperatures and aggressive fuels. PTFE offers excellent chemical resistance, but Nitrile and Viton are more common for flat gas seals. Always confirm the O-ring's compatibility with the specific gas to ensure safe and effective sealing, especially when dealing with flammable or pressurized gases”.

[A930Rocket]

Were the butterfly screws staked in?

Just thinking, you don’t want to lose a screw after reassembly!

[GTT]

Originally Posted by A930Rocket

Were the butterfly screws staked in?

Just thinking, you don’t want to lose a screw after reassembly!

Thanks. I just put in an order with McMaster with a few different seals/o-rings and hopefully one of those will work.

Yes the screws were staked. I'll either re-stake them and/or use some loctite. The screws were brass so I was able to get them out without messing up the threads.

[nickelplated5s]

If you don't have them get a set of roll pin punches. I got mine at a specialty tool shop, they can be hard to find.