I had a stream of smoke coming out of this area. Is there a way to replace whatever seal that’s there or is it time for a rebuilt unit?
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That little boot will come in a carb rebuild kit but that will not affect your vacuum.I had a stream of smoke coming out of this area. Is there a way to replace whatever seal that’s there or is it time for a rebuilt unit?
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Replace the accelerator pump. Usually included in a rebuild kit.
Smoke is shooting out from the carburetor. Around the accelerator pump area.If there’s smoke blowing out near the intake manifold- likely the gasket is blown. They definitely don’t last forever
Where are you pushing the smoke in from?
I had a conversation with JimC just the other day after noticing the exact same issue on mine (smoke billowing from the same area while looking for a vacuum leak. He strongly recommended a rebuild and recommended this repair kit, which I picked up from Rock Auto: WALKER PRODUCTS part # 15829A. It comes with the leather accelerator pump plunger, although there's a diaphragm that's wrong for these carbs (I checked mine and it was in good shape so I'm fine with that).
Jim confirmed that while it makes sense that the accelerator pump is an unlikely place for a vacuum leak, it is part of an idle circuit that can jam up and be the source of a big leak, so best to just rebuild.
He also strongly encouraged me to rebuild my own carb instead of sending it in, largely because he said it's a fun job for a reasonably inclined person
Thank you, Albert110. I do appreciate your response and all the information. Very helpful.I had a conversation with JimC just the other day after noticing the exact same issue on mine (smoke billowing from the same area while looking for a vacuum leak. He strongly recommended a rebuild and recommended this repair kit, which I picked up from Rock Auto: WALKER PRODUCTS part # 15829A. It comes with the leather accelerator pump plunger, although there's a diaphragm that's wrong for these carbs (I checked mine and it was in good shape so I'm fine with that).
Jim confirmed that while it makes sense that the accelerator pump is an unlikely place for a vacuum leak, it is part of an idle circuit that can jam up and be the source of a big leak, so best to just rebuild.
He also strongly encouraged me to rebuild my own carb instead of sending it in, largely because he said it's a fun job for a reasonably inclined person and he's at least 3 months backlogged
Are you sure this isn't a timing advance issue?
Like too much advance too soon? Probably needs the advance weight stop pin repair.
I am thinking "No". It's up too high on the carb and I think that the plunger has to communicate with atmosphere for the plunger to be able to move up and down freely. I think that in order to check with smoke you would want to remove the carb from manifold, seal up the big hole left over and then pump the smoke in. You're looking mostly for leaks below the carb.Or is that not considered a potential vacuum leak?
The rubber boot on the accelerator pump is installed from the top side. I suppose you can tease it out and install a new boot without removing much more than the accelerator pump lever. To replace the pump itself the air horn (top part of the carb) needs to be removed. It is held on by 8 screws I think. However, it's not that much more trouble to remove the entire carburetor assembly so you can work on the bench.I know I’ve read somewhere the plunger can be replaced without pulling the Carburator, but I’d rather not go that route. This isn’t a daily driver, and I’d prefer to do it all, and do it right, first go around.
I am thinking "No". It's up too high on the carb and I think that the plunger has to communicate with atmosphere for the plunger to be able to move up and down freely. I think that in order to check with smoke you would want to remove the carb from manifold, seal up the big hole left over and then pump the smoke in. You're looking mostly for leaks below the carb.
Setting your timing is a lot easier than taking the carb apart. "Bogging down" reminds me of what my engine does when the timing is too retarded. Most 2Fs (like mine) seem to prefer a bit more advance than 7*BTDC that the FSM calls for. Try advancing timing until the BB is just about to disappear from the window and see if the stumble gets better.