83 gt150 fuel pump hose routing

[motodave]

I have a omc manual, the picture of the routing is too dark for me to see, but in some if the drawn pictures it shows the hose connecting the 2 pumps to be going straight, meaning it's really short. When I got my boat they had a long hose looped down from the top pump, coming down and going back up to the bottom one. Anyone know which is correct? Thanks

 

[emdsapmgr]

Check out the original factory exploded parts diagram for your exact engine at epc.brp.com It will show the original factory hoses and will give you enough of an idea as to hook things back up. Keep in mind that some of these hoses are bent into sharp corners. These are special hoses and actually have factory part numbers. They are heated at the factory to be bent, but not kink-which is what normal "bulk" hose will do if you bend it into a tight (radius) corner. [Regular hose will kink and cause a fuel restriction.] You will see that "j" hose that you mention.

 

[1983 ercoa 21']

On mine the lower pump feeds the top pump.

 

[emdsapmgr]

Both pumps are the same part number so it does not make much difference. The factory plumbs the gas tank hose to the upper pump, then the j-hose connects to the lower, which then feeds the fuel manifold. You just have to be sure that when plumbing hoses, that they don't kink-causing a fuel restriction.

 

[motodave]

Thanks for your help again emdsapmgr! Got my recir valves replaced they were all bad, hoping for better idle next trip out

 

[motodave]

Hey emdsap, I thought I would ask - they do show 2 different part numbers for the fuel pumps, and the omc manual says there are internal differences and they need to go back to original spot. I only read this AFTER I pulled them off to put the kits in of course. May have them backwards but the motor was running. And I cannot tell a difference, I inspected them close. I guess all I can do is switch them out if it doesn't run how it should?

 

[emdsapmgr]

What happens is that when you buy the two pumps, one is the pump only, the other box comes with the same pump and that J-hose we keep talking about. That second box is actually considered an "assembly." Costs more so requires a separate part number. Technically, you need one of each part number, but you'll wind up with two of the same pumps. (and a hose)

 

[motodave]

Ah gotcha, thank you for your help once again, your a wealth of knowledge! Despite the new recirc valves my motor still doesn't want to idle, I'm going to post vid w/ all info on new thread as I'm at a loss

 

[emdsapmgr]

Idle issues are frequently caused by dried fuel gelatin clogging the small idle passages in the carbs. How long since you've been into the carbs? Does your engine have a "lean sneeze" at idle?

 

[motodave]

Thanks emdsap, I do believe it does have a lean sneeze at idle, despite the fact the plugs are wet everytime I check them. I just got done going thru the carbs for the 4th time in a little over a month, taking my time, and removing all of the jets to clean and inspect. There is absolutely no blockage, dried fuel, damage, or wrong sized jets in all 3 carbs. Went thru them completely, replaced needles & seats, new floats set to specs, all new fuel lines, removed and cleaned fuel tanks, rebuilt fuel pumps, etc. Getting pretty good and lync & sync as Ive done it half dozen times. All throttle valves completely closed at idle and moving with each other perfectly. Adjusting the idle screw raises the rpms but does not smooth it out or eliminate sneeze, pretty erratic idle. Again Im at a loss. Thank you for your assistance. Working on getting a video up like I mentioned

 

[emdsapmgr]

I take one carb and blow carb cleaner into one of the passages-noting the outflow of the cleaner exiting the other end of that passage. Then I pick up carb #2 and do that same passage, noting the outflow of it. Both should have the same amount of spray out of the exit passage. Then repeat that same passage on carb #3. Then go onto the second passage on carb 1, repeating the process. If you don't get identical spray out of the same passages, it may be clogged with dried fuel gelatin.