Logo
FULL SITE MENU

Question for Hystat on omc 5.7 l rochester 4 barrel

R

rcahill31

Regular Contributor
Hy, I posted earlier about my carburetor on our 4 winns 5.7L a Rochester 4 barrel that had to be primed if it was not used for week or less and you said to expoxy the screws under the carb which I did and a auto mechanic had gaskets that would fit the carb so he put it back together but if the boat sits for up to a week it has to still be primed, the mechanic suggested it could be the fuel pump but If I remember you stated there could be another issue to look at so if you have some more information on this problem I would appreciate your input, the auto mechanic does not want to get involved, thank you
 
I doubt that Hystat suggested using epoxy at the throttle plate base-to-main-body screws.

It's the factory manufacturing machining ports that are epoxy sealed at the well plugs during the assembly or over-hauling process.

Take a look at this web site. ............ and perhaps this web site.

These are automotive web sites, but the procedure is identical for the Marine Q-jet.

Look at these images via a Google Image Search.



Oh.... I'm not Hystat..... but I play the role of his character in the TV show! :D


.
 
Last edited:
Ricardo, I posted the question on 5-31-13 and Hy replied to try j b weld on the plugs instead I used Marine Tex, I also installed a new choke, as far as starting when it is warm, no problem, and after it has started when we use the boat and we are there at the dock for several days overnight it will start right up but leaving it set for up to a week then that is when it has to have a shot of fuel and then pumping the throttle as I turn over the engine and it starts, but it will not start after sitting for several days
 
I don't know if ethanol fuels evaporate faster than old school gas, but I have noticed everything I own that is carbureted seems to require more pumping and cranking after sitting than in the past. Or maybe I never let stuff sit this much before.
If nothing under or around the bowl feels wet, I'm not sure what you're up against. Maybe the anti siphon valve could be stuck open allowing fuel to return to the tank from the filter/lines. That's reaching though.
 
It's not likely to be the "well plugs" on the bottom that are leaking....the "newer" designed plugs rarely leak, independent of the bashing you will find posted in many spots as well as the marketeers.

The biggest contributor is the stuff they sell as gasoline today...it evaporates extremely fast and, depending upon the location, can leave the float bowl in as little as three days.

Electric pump is one solution though the easiest is to just use the boat more often (not cheaper).
 
Back
Top