Fuel Pump Bad?

[LaqueRatt]

Took the boat out again today, with the Fastwin. Started nice, ran strong, then started to falter. Stopped it, took off the cover. Air bubbles in the line again and fuel in bottom of pan. Pumped the bulb, gas dripping off bottom of pump. Snugged up the lines tried again. Same thing. Seemed like the gas was coming out around the front cover on pump so tightened that center screw a little bit. Ran a paper towel around the pump while squeezing bulb. No more leak. Started her up, same crap. Tried pumping the bulb and found she'd run well again for a minute or so. That indicates the fuel pump is bad doesn't it? Another odd thing was as I was coming back in, the bulb went flat and wouldn't pump any more. Removed gas cap on tank, still flat. Has anyone ever seen that happen?

 

[racerone]

Fuel pump is working very well if it pulls the bulb flat.------You have a blockage from bulb to the bottom of the tank I think.

 

[saltchuckmatt]

Fuel pump is working very well if it pulls the bulb flat.------You have a blockage from bulb to the bottom of the tank I think.

Or maybe the check valve in the bulb.

 

[LaqueRatt]

Bulb went flat while was squeezing it trying to limp into port, not from vacuum I don't think. Going to clean out the tank real well, but still think that fuel pump is suspect because the only way could keep her running was with squeezing the bulb. Can the check valve be removed and serviced? When I got home the bulb was working fine again. Think my boat is possessed. Can anyone recommend a marine exorcist?

 

[saltchuckmatt]

Bulb went flat while was squeezing it trying to limp into port, not from vacuum I don't think. Going to clean out the tank real well, but still think that fuel pump is suspect because the only way could keep her running was with squeezing the bulb. Can the check valve be removed and serviced? When I got home the bulb was working fine again. Think my boat is possessed. Can anyone recommend a marine exorcist?

Lol, yes I believe sometimes that's exactly what is needed.

So the check valve is in the bulb....otherwise it would pump one direction (to the engine) the fix is a new bulb. But after thinking more, and Racer said it best, junk in the tank. If the draw tube gets filled with stuff the motor can't draw fuel fast enough and the more you use it the worse it gets. Also, explains why it relieved itself after you got home.

I'd try a different tank or clean/inspect that one really well and try again. Unfortunately, since you pumped and pumped possibly tons of stuff up towards your engine you may have to go clean out everything again first.

Tank is probably your problem.

 

[tphoyt]

Just for kicks pull the line off the pump and pump some fuel into a glass jar and see what you get.

 

[LaqueRatt]

You guys rock! This all makes perfect sense and as I've been transferring fuel back and forth as I switch motors, I've been finding gray filmy stuff in my paint strainer. It breaks up easily when I touch it. No idea what the heck it is, but I could see it building up and clogging the screen on the in tank pickup.

Going to flush and clean out the tank really well and refill it with fresh fuel. Also going to test the pump as suggested.

Is there some kind of screen in the fuel pump though that can be removed and cleaned? If I pull out the center screw I can access it right? What are the chances of getting it back together without replacing gaskets? should I just leave it alone? Seems like if I got crud in the gas some of it could have found it's way into the pump.

 

[saltchuckmatt]

You guys rock! This all makes perfect sense and as I've been transferring fuel back and forth as I switch motors, I've been finding gray filmy stuff in my paint strainer. It breaks up easily when I touch it. No idea what the heck it is, but I could see it building up and clogging the screen on the in tank pickup.

Going to flush and clean out the tank really well and refill it with fresh fuel. Also going to test the pump as suggested.

Is there some kind of screen in the fuel pump though that can be removed and cleaned? If I pull out the center screw I can access it right? What are the chances of getting it back together without replacing gaskets? should I just leave it alone? Seems like if I got crud in the gas some of it could have found it's way into the pump.

Yes, center screw and you will find a screen inside. Most likely you will be able to re-seal but check seal.

Good chance you will need to clean your carb as well.

 

[Ronniewhite]

You guys rock! This all makes perfect sense and as I've been transferring fuel back and forth as I switch motors, I've been finding gray filmy stuff in my paint strainer. It breaks up easily when I touch it. No idea what the heck it is, but I could see it building up and clogging the screen on the in tank pickup.

Going to flush and clean out the tank really well and refill it with fresh fuel. Also going to test the pump as suggested.

Is there some kind of screen in the fuel pump though that can be removed and cleaned? If I pull out the center screw I can access it right? What are the chances of getting it back together without replacing gaskets? should I just leave it alone? Seems like if I got crud in the gas some of it could have found it's way into the pump.

The grey stuff is probably the inside of your fuel line getting eaten away.

 

[LaqueRatt]

Well that's disturbing. I do have new fuel lines on it now, but under the cover, not from tank to motor. Cleaned out the tank today and found some stuff in there. Do you think this could be a problem? LOL

 

[LaqueRatt]

Haven't tested the pump yet, but noticed it's leaking gas again. Around the front cover. Can I make a gasket for it? Will a standard OMC kit work on this pump, it's not square like others I've been looking at.

 

[dingbat]

Well that's disturbing. I do have new fuel lines on it now, but under the cover, not from tank to motor. Cleaned out the tank today and found some stuff in there. Do you think this could be a problem? LOL

Hose liner

 

[racerone]

You can get a new gasket for the cover.----Don't rush out and buy a new pump.----In my opinion these PRESSURE operated pumps are easy to inspect and repair.

 

[saltchuckmatt]

Well that's disturbing. I do have new fuel lines on it now, but under the cover, not from tank to motor. Cleaned out the tank today and found some stuff in there. Do you think this could be a problem? LOL

Nice stuff. At least you know your issues.

 

[tphoyt]

Some of that crap is probably jammed up in the pump and causing it to leak.
That pump needs to come apart.
As mentioned they are easy and cheap to repair and far better than anything you can buy today.

 

[Ronniewhite]

Well that's disturbing. I do have new fuel lines on it now, but under the cover, not from tank to motor. Cleaned out the tank today and found some stuff in there. Do you think this could be a problem? LOL

New hose from tank to motor

 

[LaqueRatt]

Thanks for the support guys. I assume it's mostly guys here? LOL

A few comments. Since the crap is in the tank, isolated from the lines, I don't think whatever that gunk is came from the hoses which are downstream. Since there is a fine strainer on the pickup and I guess another screen in the pump, isn't that stuff designed to keep junk out of the pump and carb? Guess I need to pull the cover and check the screen, but got my fingers crossed that none of it got further than the screens. The crud though is oddly not at all gritty and pretty much dissolves into nothing under finger pressure. I recently cleaned the carb though so it's no big deal to do it again.

What is a big deal though is as far as I can tell there's no parts for this fuel pump. Is it a an oddball? I don't see a kit for it on marinengines.com. If somebody could link me to a rebuild kit or the gasket anyway, I'd be really grateful. For reference: Engine M/N: 18502S

 

[saltchuckmatt]

Thanks for the support guys. I assume it's mostly guys here? LOL

A few comments. Since the crap is in the tank, isolated from the lines, I don't think whatever that gunk is came from the hoses which are downstream. Since there is a fine strainer on the pickup and I guess another screen in the pump, isn't that stuff designed to keep junk out of the pump and carb? Guess I need to pull the cover and check the screen, but got my fingers crossed that none of it got further than the screens. The crud though is oddly not at all gritty and pretty much dissolves into nothing under finger pressure. I recently cleaned the carb though so it's no big deal to do it again.

What is a big deal though is as far as I can tell there's no parts for this fuel pump. Is it a an oddball? I don't see a kit for it on marinengines.com. If somebody could link me to a rebuild kit or the gasket anyway, I'd be really grateful. For reference: Engine M/N: 18502S

There might be someone on here that knows where to get something, if memory serves me, but in leroys ramblings he says there unavailable. I think you have to convert to a newer style. Hopefully someone will help you out here.

 

[racerone]

These pumps operate with a PRESSURE pulse.----There are many pumps that will fit / work on your 18 HP.----Do not limit your search to the 65 model year !!----A diaphragm is easy to make.----Take pump apart and see what it might need.---No need to be scared of a simple pump.

 

[LaqueRatt]

That's good to hear, but it isn't helping me solve the problem. Sure, I can make a gasket, bet most of us here can. Can prob make a diaphragm too. From what I've read it's pretty hard to find the appropriate material. Is there something common around the house I might have? Or something I can find locally that would work? How about a thread on how to plumb in a pump for a different year? I'm guessing the main problem is mounting and pressure pulse.