How well is the fuel pump doing keeping the fuel filter full and that carb?

Temporarily install a fuel pressure gauge in line or a clear Fram filter to verify. You may be running out of fuel or something is till clogged and blocking fuel flow.

Are the fuel lines copper? or steel? they could be clogged or the air bleeds on the carb could be clogged with corrosion.
Is the accelerator pump in the carb providing a healthy pump shot?
With the engine off look down the throat and see if you get a healthy squirt.

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Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG

The fuel lines are rubber, seem fine.
There happens to be a clear fram filter that seems full, I will double check it.
The accelerator pump seems fine, plenty of squirt.

What type of two barrel carb do you have?

What is the timing set at?

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Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG

The carb. is a carter two barrel. The timing is set at 2.5 BTC as per the decal on the valve cover.

Thank you for continuing to think about this problem.

Just a reminder: it will rev up if I apply the manual choke.

If you apply the choke and the engine responds well you likely have blockage in the carburetor passages.

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Joshua

I cleaned it best I could. How would one prove this and how would one resolve it?

Substitute a known good carburetor.

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Joshua

It sounds like your carb body needs to sit in a bath of carb cleaner to dissolve the corrosion in the internal passage ways for awhile and then blown out with compressed air.

Something is blocking the fuel discharge like old gas varnish or corrosion.

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Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG

Soaking in cleaner is something I can handle.

Don't have access to a good known carb.

Update:

The filter does stay full of fuel so pump is ok.
The timing advances when rpm's go up.

I can nurse it to up revs. if I "sort of" feather the linkage by hand..
Does that change the diagnosis or treatment plan? (soaking the carb. body).

Also, NAPA gave me the wrong rebuild kit. They are not able to look this boat up so they gave me the kit for a dart (I think). Did trucks have this motor in 1971 with a two barrel carter? Or how can I get the right kit? Or even better, where can I buy a carb. for this boat?

You still need to soak the carb and blow it out. It would be nice to get the main circuit un-clogged. I am sure running the new gas through it will clean out the old built up varnish and corrosion out eventually, but soaking it overnight would really do it allot quicker.

Send SL6 Dan a PM for new carb and what is the best kit from NAPA for the Carter. I would think the truck kit would be the same or generic enough to work for you.

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Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG

Were and who rebuilt your carb?? I got a "auto zone special" and it would idle great.....until you gave it throttle. If they use a bead blaster to clean everything check for air flow through the emulsion tubes. they are in the carb held down with two screws right above the venturis. My carb was clogged up with those tiny aluminum pellets and when the fuel pushed hard enough through the carb it would crap out and Idle horribly. just fyi

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it's like a vw, sounds like a million miles an hour but goes really slow. (for now)