Driving along and engine suddenly ran really rough. No vacuum on front carb. Back carb is fine. Timing ok. 6 cylinder compression even and good.
Can not find an air leak anywhere (that does not mean there is not one)
Why would one carb have vacuum and the other basically none? Are they completely independent?
Any suggestions greatly appreciated. Totally frustated.
Lionol seed
Carb piston damper, lack of oil or cap loose?
Linkage to front carb may have come loose so that it’s not opening.
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Checked both,.10-30 oil and cap tight. thanks
I rebuilt both carbs a month ago so anything is possible! Checked and linkage is tight. Car starts easily and idles smooth but collapses when I increase the revs.
What happens to the pistons when you rev up?
How about a half sunk float?
Do you have any sort of air cleaners on the carbs? Could the interior of one or both have collapsed and is blocking air intake?
I have seen this occur when a needle is slightly loose in the dash pot piston. Worthwhile just checking the needle security on the problem carburettor.
How did you determine that there was no vacuum?
Any solution yet?
I have the filter off. Took the needle out of the dash pot and reinserted it. A friend with a 140 came over this morning and we tinkered some more and suddenly everything fell into place and the darn car ran smoothly. Took it for a test drive and no problems so far.
I guess we will never know what caused the problem in the first place, but as they say “all is well that ends well”
Used a vacuum tester to check.
Thanks for your suggestions. The float. is new and I had it out last week …no leaks. Pistons were rattling, but now that the engine runs smoothly nothing irregular.