Pingel Petcock install problem 1978 gs550e

[enriquev9]

I’m eliminating the vacuum Petcock and sprung for a pingel Petcock from Z1. I also got the adapter. I followed the instructions. Installed the adapter, marked hole with a sharpie grinder the excess metal so the pingel could fit. Deburred and filed the sharp edges. Installed gasket and adapter, then installed Petcock with Teflon tape. Filled tank with gas….. pans it started to leak from the adapter plate. Frustrating.

anyone else have experience with this install?
hiw can I fix this?
should I use gasket maker on the provided gasket?

please help

[enriquev9]

Also…. What is a good way to plug up the vacuum port on carb 3. I currently only have a vacuum cap on the port but I’m sure there are tiny leaks.

[Grimly]

I smeared the gasket with Hylomar, both sides, let it flash off, and bolted it on. Preferably use new Dowty washers on the bolts, too.
The petcock threads were simply PTFE taped.
In my case I didn't use a Pingel tap, but a H-D copy type.
Until you can lay hands on a proper vac cap, use a 1" length of vacuum pipe with a 5 or 6mm short bolt stuck in it, and wrapped with PTFE tape. That blanks it off very effectively.

[enriquev9]

Thanks grimly.

which hylomar did you use?

I searched their website and they have a big product line.

also, what does it mean to let it flash off?

yes I Teflon taped the threads of the Petcock. This was in accordance with the installation instructions. I could tell the gas was sealing from the base adapter and not the Petcock threaded into the adapter.

what would you consider a suitable vacuum cap. I just got a rubber cap from autozone and found a size that fit the vacuum port on carb 3. It’s a black colored cap. Any guidance on what you used.

[enriquev9]

Is permatex anaerobic gasket maker 51814 a suitable substitute

[Grimly]

Thanks grimly.

which hylomar did you use?

I searched their website and they have a big product line.

also, what does it mean to let it flash off?

yes I Teflon taped the threads of the Petcock. This was in accordance with the installation instructions. I could tell the gas was sealing from the base adapter and not the Petcock threaded into the adapter.

what would you consider a suitable vacuum cap. I just got a rubber cap from autozone and found a size that fit the vacuum port on carb 3. It’s a black colored cap. Any guidance on what you used.

Just the standard Hylomar Blue - it's very petrol-resistant. By flashing-off, I mean let it sit for ten minutes before bolting up, gives the solvent time to evaporate sufficiently and makes a better seal.
Something that's sold as a vacuum cap is <probably> up to the job, but who knows with the crap quality of many rubber items these days.
If the permatex gasket maker is mostly silicone, I wouldn't use it on a petrol joint - early on, I discovered silicone sealants don't live well with petrol.