carter afb float height adjustment?

oldwood69 · Post by **oldwood69** » Sun Jul 31, 2011 5:37 pm

Does anyone know the correct (marine application) float height adjustment (both up and down) for Carter AFB carbs on chrysler 383 motors? I have completely rebuilt both carbs on my 1969 chryslers (in SeaVoyager) and motors run amazing. My problem is that they will only take "full" throttle for about twenty to thirty seconds before all of the fuel has been sucked out of the float bowls and they start to sputter. This condition can be repeated from either idle or cruising around 2100rpm which is the highest rpm the floats can keep up with. Symptom is on both motors and all other items that can cause such a symptom have already been addressed. When I rebuilt the carbs I set all of the floats to the spec in the rebuild kit, which was for cars. I've been told the marine application specs are different and I think once adjusted my problems will be solved.

Thanks in advance!

LandVF36 · Post by **LandVF36** » Sun Jul 31, 2011 9:37 pm

I would wonder about the fuel pressure? Do you still have the standard diaphram mechnical fuel pumps? Do you know what PSI they are pushing? They are not real expensive but if you look to replace them, be sure to get the marine replacement type. The automotive stile have a purge hole that when they fail would leak to your bilge and make you go boom! the other idea is at any auto-parts store, for < 20 you can get an electric pump to test with. Wire it in series with a oil presure switch (alarm) so it can't pump unless you have oil presure for safety.

oldwood69 · Post by **oldwood69** » Sun Jul 31, 2011 9:51 pm

Good thoughts on checking the fuel pressure, I have already gone through the fuel delivery system and there are no apparent issues there (all filters replaced even twice on water sep. Filters as well as pressure checks). Even if there were issues there each motor has its own fuel pump and the problem is identical between both motors. I rebuilt both carbs with identical kits and set float levels the exact same on both...I really think it is due to using "car" settings for the floats vs "marine" settings...I just don't know what those numbers are.

prowlersfish · Post by **prowlersfish** » Sun Jul 31, 2011 10:39 pm

Sounds like a deliver issue to me also , But if you think is a floats issue the right float level should be in the kit instruction matched to the carb number , ( the marine carb and car carbs are not the same numbers) .

Did it do this before you did the carbs ?

g36 · Post by **g36** » Mon Aug 01, 2011 7:05 am

i believe it is 5/16 . you may also check your anti siphon valves on the fuel tank

whats your floats set at now?