fuel dripping again...

[bishop12]

Ok 80 MODEL 140 Mercruiser,with a rochester 2 jet carb. I have rebuilt the carb and adjusted the float level untill im sick of it. Still dripping into carb after I shut it off. I also tried a known good carb that didnt drip,but drips on my engine. When I rebuilt the carb it had a small spring loaded rubber deal that went inside of the fuel filter. The kit did not have this in it,could it have something to do with the dripping. The only other thing that I can think of is that the fuel pump is putting out to much pressure. Has any one had to install a pressure regulator.

 

[The Marine Doctor]

Re: fuel dripping again...

Are you using an electric fuel pump?<br /><br />TMD

 

[loadnet]

Re: fuel dripping again...

Biship - you can do a fuel pressure test right where the fuel line enters the carb to find that out real quick..<br /><br />You can also try this...<br /><br />- start the engine..<br />- remove the aircleaner.<br />- As you are looking down into the carb watching it drip, drip drip.... try tapping on the side of the carb float bowl and the heads of the screws holding the float bowl in place, and lightly on the housing of the float bowl and see if the dripping STOPS.<br /><br />- If it stops dripping ANYTIME during the hammering process, your float is either set to high, (sticking in the up position) or the needle seat is NOT shutting down the fuel when the float rises.<br /><br />You'll have to tear the carb apart again and start over or bring it to a joint that will do it for you, and guarantee their work.<br /><br />If the dripping does not stop no matter how much you hammer on it.. kill the engine and try blowing it out with an air hose then spraying WD40 into the hole that goes to the float bowl.<br /><br />Start it up again and repeat the process of hammering if it's still dripping. GO EASY on the hammering, as in place a rag over the screw heads then tap on them.<br /><br />If the dripping persists - then - head for fuel pressure problem. Test the pressure coming in and see what you have.. it should be around 5 to 8 psi tops...<br /><br />CHF

 

[bishop12]

Re: fuel dripping again...

No its the standard fuel pump that came on the motor. The tapping on the screws and the top of the air horn doesnt stop it from dripping either.<br />Has no one ever seen the little spring loaded rubber deal that goes in the filter. I have also seen these on autos to but it doesnt make any difference on them if you choose not to use it. Also does any one know if these fuel pumps have any adjustments on them, for pressure.

 

[bishop12]

Re: fuel dripping again...

ok I closed the float up a little more and the dripping stoped. Now it pops thru the carb under exceleration.Does this mean a lean mixture?

 

[The Marine Doctor]

Re: fuel dripping again...

Does this happen when you first move the shifter to WOT?<br /><br />IF so..you need to do some work on your accel pump.<br /><br />And possibly some adjusting on the mixture jets.<br /><br />TMD

 

[CRT Skiff Crafter]

Re: fuel dripping again...

Hi Bishop12.<br /><br />As Marine Doc mentioned, sounds liks an accelerator pump issue. Stating the obvious, but have you verified that your getting the shot of fuel down the throat that is provided by the accelerator pump? <br /><br />You can easily check it by having the first mate advance the throttle while you peer down the throat, or if no first mate is available, disconnect the throttle control linkage and advance the carb throttle. You should see a nice squirt from the pump discharge nozzle. If you don't, it may be as simple as taking a fine wire and carefully unclogging the holes in the discharge nozzle. It is also possible (at least on my carb) that during reassembly you can get the linkage orientated incorrectly and the accelerator pump will not be accuated.<br /><br />All basic stuff, but the stuff that can elude a person when you get too far inside the forest. <br /><br />I recently rebuilt my carb and had this same issue.<br /><br />Good luck.<br /><br />Regards, crt.