Need help with fuel pump

[Fishingaddict88]

1988 4 cylinder 130hp 3.0 (181 cid)

I have been having fuel issues lately. Currently have the carb off the boat for a rebuild. Today though as I was messing around with the boat I noticed I have gas in my oil. Correct me if I'm wrong but my first thought is bad fuel pump. Now, the million dollar question is to which one? I am unable to locate a serial number on the engine, I've looked for hours. I know it's a Carter fuel pump, cannot locate a number on that either. I'm not real knowledgeable on fuel pumps but I did notice the bottom half looks in halfway decent shape, rather new actually. The top half that goes into the engine is all corroded and nasty looking. I assume that top half that goes into the engine is my problem. Is there anyway I can just replace the top half or do I need a whole unit? Will any fuel pump for a 3.0 work? My bowl is on the bottom If that helps you visualize.

This boat is becoming a nightmare. My first boat and although I'm learning a lot, it's coming with a hefty price tag.

Anyways, any reponses are highly appreciated.

 

[Snakecan2]

welcome to owning a boat. if you haven't heard it, there are only 2 time a man is truely happy in his life. Getting the new boat(even used) AND getting ride of the POS.

Do you have an electric fuel pump as well? or just the mechanical one?

The mechanical one should have a weap hole so when the diapraghm goes bad it will leak out for you to know. But if it is plugged up and the seal around the rod is worn/shot i guess you could get fuel in that way. If you have an electric pump as well then if the float is stuck you will be pouring gas down the intake.

I think you would need to post more info on your boat, than just year and hp, due to the possible configurations. That way some of the veterans here could give you better advice.
Good luck

 

[Rick Stephens]

Not quite right. A mechanical MARINE fuel pump should have a clear tube running from the pump to the intake side of the carburetor. If the diaphragm breaks, instead of dumping fuel into the motor, thereby making a bomb, it floods the carb and kills the engine. The clear tubing acts as a sight tube so when your engine starts running bad, if you see fuel in the line then you know you lost a pump.

Really old mechanical pumps had a clear glass bowl that acted as the sight tube. If the bowl had fuel in it then the pump is bad. Those were made obsolete and the clear tubing became the norm.

Anything beats filling the engine and potentially the bilge up with fuel and making the boat go boom.

 

[Fishingaddict88]

Unfortunately I've heard that saying, lol. Thought I'd be the odd man out. Nope!

It is a mechanical pump, not leaking any that I've noticed. I've tried posting pictures but it won't let me. Is there any other service besides photobucket?

 

[Fishingaddict88]

Rick, I've only read about these clear sight tubes and such. Although mine is mechanical, there are no clear tubes. Mine is black.

 

[Rick Stephens]

If you resize your pictures to under 700k in size - plenty BIG - you can post them directly to the forum by uploading using the button.

All Marine rated mechanical pumps will have some sort of way to handle a ruptured diaphragm. If yours does not, it is probably not a marine pump.

 

[Fishingaddict88]

https://m.imgur.com/lx9x4jd?r

https://i.imgur.com/VXvVQEd.jpg

https://i.imgur.com/ZYTVJPQ.jpg

 

[Fishingaddict88]

Not sure how to resize on mobile but found an easy uploading site. It kept telling me they were not .jpg format when I clicked that button.

It appears to be a marine pump but they switched out the clear tube with a black line.

 

[Rick Stephens]

We ll, it is a marine pump, just someone replaced the site tube with a rubber hose.

I took your picture, which was over 40 inches wide and 72 inches tall and made it 12 inches wide.

 

[Fishingaddict88]

Thanks Rick

 

[Fishingaddict88]

Theoretically though... If I undo that black hose and there is gas in there. My pump is bad?

 

[Fishingaddict88]

That would actually make sense. I've been running really rich and my engine bogs down at W.O.T.

 

[Rick Stephens]

Theoretically though... If I undo that black hose and there is gas in there. My pump is bad?

That is correct.

 

[Fishingaddict88]

Welp, no gas in "sight tube". It is possible it could have evaporated though. I've had the sight tube disconnected from the carb for like 2 weeks.

Any thoughts? Replace the pump anyway?

 

[Rick Stephens]

I don't know if the fuel will stay in the tube indefinitely, or if it drains back into the block. Never had a split diaphragm on a boat pump. Normally, I would expect you would hear the engine running rough or die, open the cover on the engine bay and see fuel in the tube. Wait a week, probably all drain back.

 

[Fishingaddict88]

I'm gonna try to swap the float in my carb and adjust it accordingly. I tore the fuel pump apart and the diaphram looks in great shape, as well as the rest of the pump.