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-   -   carter afb (weber) carb factory jet sizes? (http://www.mariahownersclub.com/forum/mercury-mercruiser/9333-carter-afb-weber-carb-factory-jet-sizes.html)

Txtruckerpaul 05-21-2014 02:37 AM

carter afb (weber) carb factory jet sizes?
 
Been having a difficult time finding info on this. I'm having big issues with my 96 talari 7.4 running very rich. I've tried every adjustment I can think of and no dice. Finally did some digging and noticed the metering rod springs were different from each other. I did find out that they are supposed to be the same. Got some new springs and its still running rich, but not as bad. Its making me wonder if the goon that put the different springs in has also messed with the metering rod sizes themselves and maybe even the jets. Does anyone have any info on what the factory size for the jets and metering rods are? I've searched and found a billion different configurations. My carb is a 4760s carter afb 750 cfm. The only numbers I could find were on the metering rods. One rod has 16-338 on it and the other rod has 16-339. Any help on this would be very much appreciated

ColoradoDiablo 05-21-2014 03:01 PM

Re: carter afb (weber) carb factory jet sizes?
 
I have a factory carb manual Paul for the Webers.
Let me do some digging in the "boat room".
I'll get back as soon as possible , probably tonite:wink_thumbup:

Hudson River Steve 05-21-2014 03:18 PM

Re: carter afb (weber) carb factory jet sizes?
 
Paul,
From past experience, uncontrolled running rich is usually a sign that the float level is too high. Have you verified that the float level is correct? Good luck.
Steve

ColoradoDiablo 05-21-2014 03:44 PM

Re: carter afb (weber) carb factory jet sizes?
 
Paul ,
Take a look at this:

http://www.google.com/url?sa=t&rct=j...,d.aWw&cad=rja

Not from my manual but basically same info.:wink_thumbup:

Txtruckerpaul 05-21-2014 03:55 PM

Re: carter afb (weber) carb factory jet sizes?
 
Steve, the float is set to spec from my book. I did get a metering rod spring kit and put the proper springs in and that has seemed to help a lot, but still a little rich since I can smell it. Larry, thanks for the good info. Going to take a closer look at my choke and see if it's in proper order. Thank you for the link

Hudson River Steve 05-21-2014 07:17 PM

Re: carter afb (weber) carb factory jet sizes?
 
Paul,
How is your boat running? Does it idle and accelerate well? What I am saying is that marine engines tend to run rich as they run very cool...particularly at idle. My fuel injected 7.4 flat out stinks of unburned fuel...but it idles smooth as glass and accelerates just fine.
Steve

Txtruckerpaul 05-21-2014 07:27 PM

Re: carter afb (weber) carb factory jet sizes?
 
Steve, it seems to run ok, idles good. Bogs a little at wot, thought. My plugs are sooty black from running rich and it's reeks of raw fuel pretty bad when idling

Hudson River Steve 05-21-2014 08:16 PM

Re: carter afb (weber) carb factory jet sizes?
 
Paul,
If the plugs are sooty then you are right to be concerned...they tell the story. Beside your choke, there are only a few other things I can think of at the moment. Have you checked your fuel pressure? Maybe it is high and pushing the needle off the seat? Lastly, if you have installed the correct metering rods and springs...is it possible that the seats are worn?
Happy hunting.
Steve

Txtruckerpaul 05-21-2014 08:24 PM

Re: carter afb (weber) carb factory jet sizes?
 
Steve,
The choke seems to be ok. Haven't checked fuel pressure. My metering rods have some weird numbers on them that I can't find any info on. My rods have 338 and 339 on them. Spec on my carb calls for a 6542 (two step rod. That's the part that has me baffled into thinking that someone put these in here and put a different size spring under each one.

Hudson River Steve 05-22-2014 12:59 PM

Re: carter afb (weber) carb factory jet sizes?
 
Paul,
You may be right...sounds like someone may have put a Rochester or other metering rod in your Carter. The parts are cheap enough...why not buy the correct rods, springs and seats for your model and start with known good parts...or can it altogether and put on a new marine Edelbrock carb and enjoy your summer.
Steve


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