46 Mercury Issues that test me
 

1946 Merc.
12 volt conversion with solid state ignition, electric fuel pump,disk brakes front.
car has sat a while, running fine when i put it away. Starts right up , idles great.
When Accelerating, backfires through exhaust, great sucking noise thru carb like its choking out, sputters and dies. have not rebuilt carb. Suggestions please.

Re: 46 Mercury Issues that test me
 

Just a stab in the dark, but if it's making a sucking sound that could indicate a vacuum leak of some sort.

Re: 46 Mercury Issues that test me
 

Because you have solid state (electronic) ignition. If you don't have spiro-wound spark plug wires similar things can happen.

Re: 46 Mercury Issues that test me
 

Thanks for your response. No vacuum leak that I can find. I think the next step is to rebuild the carb.

Re: 46 Mercury Issues that test me
 

Correct plugs had been installed at the time of converting. As mentioned, car ran well until i put it away. I believe a Carb rebuild is in order. Thanks

Re: 46 Mercury Issues that test me
 

It sounds a lot like my car did before CharlieNY rebuilt the carb. My accelerator pump wasn't working at all, really stumbled on acceleration, smoothed out if you feathered the accelerator as speed picked up.

Re: 46 Mercury Issues that test me
 

It's the plug wires that need to be Spiro wound or resistive, with these fangled electronic ignitions.
Martin.

Re: 46 Mercury Issues that test me
 

Was not referring to 'plugs' but plug 'wires'.
And then again it could be float level or accelerator pump.
This is an excerpt from a Mallory Unilite installation instruction sheet.