Leaking fuel at carb. HELP!

[tank1949]

The fuel drained out of the carb as it was sitting, so it's not pumping author the motor running. It is definitely an electric pump though and runs with the key "on". Thinking about it, it doesn't turn off on its own. Not sure if that's what you meant. So what do I do with the pump?

Scott is 100% correct. Buy manual and read part of electric fuel pumps or we will all read about u!

 

[timharper89]

The oil pressure switch is next on my list. Waiting on the switch to come in. I just recently bought this boat and have learned several things the P/O did that he didn't have done or didn't do that he should have done. Hoping to get the fuel issue taken care of. Pooling fuel in the carb is pretty dangerous and is taking top priority at the moment

 

[AShipShow]

Based on the sketchyness of all this, I would also verify that your fuel pump is SAE J1171 and/or USCG approved.. there should be a marking on it somewhere... if not, get a new pump

 

[timharper89]

The pump does have a marine sticker on it. Do I need a special fuel pressure regulator for marine use as well, or will aa automotive regulator work If the pressure is too high?

 

[AShipShow]

If the pressure is too high, you need a new pump. There isn't a regulator for the correct setup. The needle and seat should be sufficient to stop the flow. You're fuel line pressure should be between 3-7 psi. Test your fuel pressure and go from there.

 

[timharper89]

Fuel pressure was 10 psi. Definitely not 3-7. You're saying I can't buy a fuel pressure regulator and regulate it to 6 psI ?Why is this not something I can do?

 

[AShipShow]

Not saying its not possible, but if it were me, I wouldn't want to introduce an additional component into the system that wasn't designed to be there in the first place. If you do go that route, make sure the fuel pressure regulator is USCG approved. Personally, I would switch back to the mechanical pump that was meant to be on the motor in the first place and call it a day.

 

[timharper89]

So I'm having a hard time finding where the original mechanical fuel pump would have gone.

 

[dave 7 0]

What type of electric fuel pump? There are electric fuel pups that make way more pressure that a needle can stop. a low pressure pump for a carburetor only makes about 5 to 7 pounds of pressure. Anything more than that will blow the needle off the seat and flood the carb. Also is the float set properly?

 

[timharper89]

This is the only thing I could see that looks like it could possibly be something ,but the see no bolt holes, and this opening doesn't go anywhere.https://photos.app.goo.gl/h4C9eMkcnuqJ2EKA6

 

[dave 7 0]

Is that a V-8? If so that looks like the location and size opening for a mechanical fuel pump. I have no idea how oil hasn't been pouring out of there.For the older blocks when you removed the a mechanical pump to use an electric one you put a block off plate and a gasket to seal it up. this must be a newer engine the rectangular hole is still there but the hole for the push rod must not have been cut into it. also you have no holes tapped for the bolts

 

[Bondo]

Ayuh,.... That is where the fuel pumps used to mount,.....

How 'bout a picture of the fuel pump ya got,.....

 

[AShipShow]

Ahh.. things are adding up... how long have you owned this boat? The 4.3 motors switched to electric fuel pumps around the early 90s I believe. The gm blocks were cast with mechanical fuel pump area sealed off. Thinking your block was replaced at some point and an electrical pump was (improperly) installed.

 

[tank1949]

Fuel pressure was 10 psi. Definitely not 3-7. You're saying I can't buy a fuel pressure regulator and regulate it to 6 psI ?Why is this not something I can do?

If it is not a marine certified 12 volt electric pump and not plumbed to special oil pressure switch, you are treading on thin ice. Go out a buy a Sierra Marine electric pump and google how to install oil pressure in series. Good luck.

 

[timharper89]

It is a 4.3 v6. That "hole" is no more than a cave. I stuck my finger in and it does not go through. Just a bunch of dusty rust in there. Doesn't look flat like it could hold a gasket very well either. Here is my current pump https://photos.app.goo.gl/PLGoLfR7HDEbUCUw8

 

[timharper89]

Yes it seems the incorrect fuel pump was put on (and incorrectly at that). I didn't know about the blocks. I've only has this boat about 5 weeks. Had a few issues I knew about, and apparently some I didn't. P/O says the engine was rebuilt about 7 years ago (by owner previous to him) and confirmed by marine mechanic that it "appeared to have been rebuilt".

 

[AShipShow]

So.... not sure what to tell you at this point other than I would buy a SAE J1171 rated electric pump that provides around 6 or 7 psi, wire it correctly through an oil pressure switch, AND using A2 and or steel line.

 

[timharper89]

So I've been looking at fuel pumps. Most I can find have a very high gph (70+) flow rate. Is this an issue? I only need about 20-30 gph max. Is that just a possible rate maximum rate?

 

[tank1949]

So I've been looking at fuel pumps. Most I can find have a very high gph (70+) flow rate. Is this an issue? I only need about 20-30 gph max. Is that just a possible rate maximum rate?

Pump looks clean and able to get model # from it for u to research. Google model or try to find photo to compare. PSI is the main concern. 4-7 is about right for 6-8 chevy motors. Just as long as it is certified marine.

 

[timharper89]

Yeah I found that pump from the model. It is rated for 9 psi (it's pumping 10), so whoever put it on didn't pay attention to that detail.