No Accelerator Jets after long layup
 

Started the car today after a 2+ year layup. 40IDA Carbs were drained before layup.

After resolving some stuck float issues, I noticed that none of the accelerator jets on either side are working.

What’s the most likely cause? The jets themselves don’t seem to be clogged.

The accelerator pump diaphrams can get hard.

Obviously it’s been a while since I’ve worked on my Webers. Where does one get parts these days?

Pierce Manifolds for one. Parts Klassik.

Just went thru something similar when installing a pair of Webers that I rebuilt a few years ago but just got them back into service. Mine turned out to be a stuck check valve in the float bowl that supplies the accelerator jets circuit. Agree with John on Pierce Manifolds - great to work with in my experiences.

It’s been a while since I’ve worked on my Webers so I’ve forgotten a lot.

Can you describe just where the check valve you’re referring to is located?

Bottom of one of the float bowls. Take the float out to see better.

Thanks very much for that picture.

I’m wondering if I should just plan on replacing them?

They aren't that difficult to tear down and rebuild. Get the kits and spend a couple hours

LOL. I meant replace the check valves, not the carbs :)

I’ve rebuilt them before.

Do you guys think removing the carbs from the car makes the re-build that much easier? My car is on a lift so I can at least get it at arm level. Still have to lean on though.

Absolutely remove the carbs to do a rebuild.

If you want to replace the accelerator pump diaphragm only, you can do that without removing the carbs from the engine. Quick and straightforward.

I’m debating about whether or not to do a re-build.

The car has been sitting for three years. It runs, but lots of backfire and as the title of this post suggests, the accelerator jets don’t work. Sometimes if feels like a re-build would be a cure-all, but I’m feeling lazy about putting in the work!

If you let it sit for 3 years with ethanol-contained gas in it, You most likely will end up disassembling it to clean out the green crud.

You can do it now, or you can do it later...

No accel jet function will certainly cause lots of backfiring, as well as too small idle jets, improper mixture adjustment, retarded timing, etc.