Fuel Problem?

[solidgoldcaddy]

ok so im new here and i probably will mess terms up, but here goes. my first boat we just bought is a 1990 forester 1800 gt, with an omc 4.3L cobra 4BBL. the guy we bought it from put a whole new engine in, did a good job. but he added an electric fuel pump. the pump has 2 wires and it was mounted directly to the block under the manifold. rubber and stainless gas lines. so heres the problem. the pump has a pressure saftey switch. and has a primer switch so you can prime the carb then fire it up. it fires up and runs a little cold blooded right away, but after a few minutes its fine. then we took it out and ran between 1000 and 4000 rpm and vary the speed cause we are new and just trying to get a feel for the thing. the first time we had it out, i did the above and after about 30-40 minutes of that, the boat slowly sputtered and died. would not restart. so i dumped some gas in the carb and that would fire, but once it was burned, would not restart. after about 15-20 minutes of waiting, it would restart and then run fine for about 30-40 minutes and then die again. same problem. it does it in the driveway and it does it in the water, yes i hooked up the water to the ears to run it out of the water and i have worked extensively on car engines, this isnt too far off from that. so i figured it was a fuel pump problem. so i relocated the pump in the side compartment and ran it like that in the driveway for a good 45 minutes, it still does it and the pump is hot even though it isnt near the engine heat or any other heat source. the vent tube is clear, the pickup tube is clear, the filters are clear and new and i cant figure it out. should i replace the fuel pump? is it too small and thats why its heating up??? how much psi should be running to the carb from the pump??? is it vapor lock? i have a few questions and am stumped. sorry if that was a long post about a 2 sentance problem, but i like to inform to the fullest. thanks in advance to you guys. ive read here for a while and its the best source for info. thanks again. chris

 

[solidgoldcaddy]

Re: Fuel Problem?

btw the pump looks like this carter that i found a pic of.

http://www.carterfueldelivery.com/fuelpumps/graphics/electric/solenoid.jpg

 

[Haut Medoc]

Re: Fuel Problem?

Welcome to iboats.....
Sounds like a fuel restriction to me, possibly a clogged tank vent....
Read this.....http://forums.iboats.com/showthread.php?t=167561
I wonder if they put an electric pump in to try & mask another problem...​

 

[solidgoldcaddy]

Re: Fuel Problem?

Welcome to iboats.....
Sounds like a fuel restriction to me, possibly a clogged tank vent....
Read this.....http://forums.iboats.com/showthread.php?t=167561
I wonder if they put an electric pump in to try & mask another problem...​

i see in there is says faulty anto siphon valve, where would that be located on my boat? what problems could be masked by putting in the elec. pump? i checked the vent and its clear. and i just changed all the filters. but why does the pump get so hot and then after 15 min to cool is fine? is it supposed to get hot? where does everyone else have their elec fuel pumps mounted if NOT in the tank? thanks for the fast response.

 

[solidgoldcaddy]

Re: Fuel Problem?

he said there was water in the tank when we bought it, but it ran perfectly when we tested it out with them. then we took off the filter and emptied it into a clear container and there was water in there, but a very small ammount. dont know if that helps. also, what is a external canister? does that mean the water separator?

 

[Haut Medoc]

Re: Fuel Problem?

i see in there is says faulty anto siphon valve, where would that be located on my boat? what problems could be masked by putting in the elec. pump? i checked the vent and its clear. and i just changed all the filters. but why does the pump get so hot and then after 15 min to cool is fine? is it supposed to get hot? where does everyone else have their elec fuel pumps mounted if NOT in the tank? thanks for the fast response.

I'm not really an OMC guy....
That said, the anti siphon valve is most likely to be located by the fuel pick up where it comes out of the tank......
I would check the pick up screen on the pickup & try to drain the fuel tank as much as possible to get any carp out of it.....
The pump itself may be getting hot trying to overcome the suction caused by the clogged screen.....
Just something to check.......
I would run it some more & check the filter again....
If you see more water, replace the element......​

 

[WAVENBYE2]

Re: Fuel Problem?

I know this might sound silly, but do you think you might have a break in the wire??? We went boating last Thurs, Every thing was running great, slowed down to go through a no wake zone, so we were putting along all of a sudden it died(been running around a good hr.) I turned the key to try to restart her and didn't hear the electric pump I took off the cover and asked my wife to just turn the key(no pump) I checked the connection from the pump wires to the boat wires(hard down wires) asked her to turn the key and the pump kicked in and was pumping again and fired right up, didn't have a prob. again all day(4 more hours of running around) and no more probs. It only did it when it was hot >>> PAT

 

[Maclin]

Re: Fuel Problem?

I would think the pump would get way too hot mounted to the block. I would try to relocate it, and go with steel lines if you can, braided if you must, but watch the rubber only lines...use USCG spec rubber line, twice as thick and much better insulated. No less than 3/8 inch.

 

[solidgoldcaddy]

Re: Fuel Problem?

the pump always has power, i checked that first. and the pump has been relocated to the battery box, and rubber lines were already installed.

anyone have an easy affordable way to siphon all the crud out of the tank should there be any in there? besides swallowing gas?

thanks guys for all your help, being a car mechanic, i can relate to not seeing a problem, and being expected to find a solution over the internet. very difficult indeed. thanks though. any more ideas send em this way. im going to check the pick up and the siphon valve, how will i know if the siphon valve is bad???

 

[Coors]

Re: Fuel Problem?

Probably, you have a restriction in the tank intake system. Search and find Don's sticky. Wave- get off the cute fonts, it is possing everybody off.

 

[solidgoldcaddy]

Re: Fuel Problem?

ok so i checked the pickup tube and its free and clear, there was no valve that i could see in it or on it. i guess i wasnt sure what to look for. but def. no valve.

i should probably mention that when we test drove the boat with the owner, it ran fine and did not do this at all. then when i got it he said there was water in the tank, so i bought 2 bottles of gas dri from mercury and dumped them in the tank. i heard alcohol will increase the chance of vapor lock, and me personally am leaning toward that. i have found no other evidence to prove otherwise, and i would like to be sure. so to rule it out, i think i will run this tank down empty and clean the rest out myself, and then try the straight 89 oct and see what happens. any thoughts? could i be wrong on the vapor lock theory?

 

[Reel Poor]

Re: Fuel Problem?

Have you checked the voltage to the pump while the pump and engine are running. High or low voltage could be a culprit. Also be sure to check the ground circuit.

 

[solidgoldcaddy]

Re: Fuel Problem?

Have you checked the voltage to the pump while the pump and engine are running. High or low voltage could be a culprit. Also be sure to check the ground circuit.

i know, but why would it do it after a certain time, like a half hour then do it? somethings not jelling.

i just went out to start it and it fired up fine and this time it ran for even less than 15 minutes and just died. then wont restart. i can hear the pump when it cranks, and i also checked the voltage when it was running, and i had 14.56 so thats normal. then it dies and nothing. the pump was barely warm, not even hot. im frustrated.

im wondering if the carb has a problem with it or something. the guy rebuilt it when he did the engine and he was a marine mechanic for years. idk just speculation i guess...

 

[Reel Poor]

Re: Fuel Problem?

If, and I do mean IF it's a voltage supply problem the pump can run on low or high voltage until it overheats then quit. You will just have to check the voltage with a volt meter to see IF this may be a problem. It would also be a good idea to check the amperage draw of the pump.

 

[ziggy]

Re: Fuel Problem?

i don't know the spec. on yer fuel pump output. but i would want to know if it's puttin out what it's supposed to for your engine. also, ya could try a remote fuel tank with some nice fresh fuel in it. plug that into yer fuel pump and see what happens. if it still dies, ya've eliminated everything before the fuel pump as a possible problem........the link that haute put ya onto might be something to get onto......

 

[Reel Poor]

Re: Fuel Problem?

Give this test a try. You could also use an auxiliary tank plumbed directly into the fuel pump eliminating any problems that may exist with the boats tank and fuel supply circuit.

Testing Your Boats Fuel System

 

[solidgoldcaddy]

Re: Fuel Problem?

tomorrow i have a new water separator comming, and im going to try the remote tank to eliminate the fuel in the tank in the boat itself. i also dont know the specs on the pump, but im sure i can find out what the factory mechanical pump should put out, and then get a gauge and measure the electric pressure. if its low, theres the problem, if not, move on.

also fellas i was thinking, when we picked it up there was a substantial ammount of water emptied from the separator. then i was thinking maybe some water got passed the filter and got into the carb. in that case, would that cause what is happening now? if so, how is it rectified?

 

[solidgoldcaddy]

Re: Fuel Problem?

ok so i took off the fuel pump and ran it with clear hose, with one end being shoved down the fill neck of the boats gas tank, and the exit end a red gas can on the ground. and just like it did before it ran for a while (15-20) min, then the pump lost suction, it still ran, but the fuel in the hose was not moving and, in fact, it actually returned to the tank. so im going to order the carter universal electric pump and install that. thanks fellas for all your help. i think i finally found it. if i need more help, ill be sure to ask. chris

 

[Reel Poor]

Re: Fuel Problem?

Be sure the new pump is a Coast Guard Approved marine service replacement part. Automotive parts are illegal in an enclose bilge compartment.

 

[solidgoldcaddy]

Re: Fuel Problem?

i know, thats why im getting the carter p4839 pump. its the spin drive type and its appoved for marine use. comes with everything, and i already have the oil pressure saftey switch installed on this one. the guy who built it used a universal pump for like automotive applications. i know i have seen people argue that marine and auto are the same. well, they dont make things marine approved for no reason. saftey is the main goal, it isnt to gouge our pockets, just like things arent street legal on cars. im switching it out on monday and hopefully that will rectify the problem once and for all. thanks