Edelbrock carb rebuild?

[flatiron14]

Firstoff, I have a '92 Regal bowrider with a 305 Chevy/alpha one with a four barrel Edelbrock Carb. In the driveway, she starts up great and has no delay when throttled. In the water, there's a delay when you throttle it real hard, then it catches up and once at plane it runs great.

Here's my solution: While trying to start the boat a time or two, I've had backfire out of the carb... So I figured the accelerator pump spring must be gunked up/worn out so I was planning on rebuilding the carb. Is this what I need to do to fix the problem? And is there a difference in an automotive carb rebuild kit and a marine carb rebuild kit since it's all internal parts?

-James

 

[flatiron14]

Re: Edelbrock carb rebuild?

Really? No one has any suggestions?

 

[cr2k]

Re: Edelbrock carb rebuild?

It's been awhile since I've been in to an AFB or Edlebrock.
Sounds kinda like power valve more than accel. pump. But either way I would say a tear down would be helpful.

Yes an automotive kit should be fine and they cost less, usually, Check Kragen.
If you get one with a new spring for the accel. pump use which ever is stiffest.
A lot of the kits come with new one that are softer and don't work as well.

One of the best things you can have on hand for a carb rebuild is a cutting torch tip cleaner. Good for getting in the small holes.

 

[dakine]

Re: Edelbrock carb rebuild?

 

[mkast]

Re: Edelbrock carb rebuild?

So I figured the accelerator pump spring must be gunked up/worn out so I was planning on rebuilding the carb

Have you looked at the carburetor to verify the accelerator pump isn't working?

 

[Bondo]

Re: Edelbrock carb rebuild?

Ayuh,..... Here, is everything you ever wanted to know about your carb....
If you want to cross reference the Spec.s,...
Open any of the Merc. manuals for the Merc./ Weber carbs used on the later motors, as they're the Same carb...

 

[zbnutcase]

Re: Edelbrock carb rebuild?

The automotive kits don't have the seal for accel pump plunger. And NEVER use wire or torch cleaners to clean anything in a carb!!! 'nutcase

 

[magster65]

Re: Edelbrock carb rebuild?

I have some tuning experience with these carbs.
It sounds like a lean or rich condition during one of the carb transitions possibly.
First off... make sure the carb is spotless inside... if it isn't, you're wasting your time. Also check your timing. It being retarded or advanced too much will only add to fuel problems.
The carb; if there's more than one hole, put the accelerator pump actuator rod in the hole closest to the carb and try it. If that makes it worse, move it to the outer one or, if it doesn't do anything put it back to the middle one. Check for plunger condition and then if it's not the accelerator pump, buy a tuning kit and do an experiment or two. Replace your primary metering rod spring with a slightly heavier one. This will richen the engine more quickly at slow speed throttle increases. If this has a positive effect, try the same on the secondaries. If this makes it worse, go the other way. Go 1 increment at a time and write down your results (and write down what rods and springs are in there before you start). Keep an eye on your temperature and listen closely for pinging if you're going leaner.
One last thing, when you're happy with the way it's running and everything seems good... take a run in the boat at full throttle (a minute say) and quickly slow down and shut it off. Carefully pull a front spark plug on either side (use gloves) and look for a rich / lean condition. How to read a plug information is everywhere. I just Googled 'how do I read a spark plug?' and the NGK site was at the top. It has good pictures and a guide.
The kit also somes with a handy tuning guide.
Hope this helps.
Cheers!

 

[relstabw]

Re: Edelbrock carb rebuild?

I think Magster gave you some good advice about the metering rods. These carbs respond very well to metering rod spring changes. They generally come on the lean side so heavier springs solves this. I would also check to make sure the ignition timing is advancing when you accellerate that could also account for both the backfire and hessitation. Good luck.