OMC Pressure Tank

[Goman]

Hello All,

It’s a 6 gallon tank I rebuilt worked fine running a motor in a barrel for about 20 minutes. 3 trips to the river later motor won’t stay running unless you pump the tank. I knew of problems with the pick up tube and check valve from the get go. I’ve soaked it in lacquer thinner, carb. spray, acetone and used air pressure from the start. Seems fine when put back in to the tank. The last 2 times I’ve taken it apart it’s been the pick up tube/check valve. Has anyone cut into this pick up tube to get to the check valve and put it back together? Am I missing something?
Kind of frustrated
Glen

[billw]

First, don’t forget that the rubber pressure valves in the MOTOR can go bad….Once the motor has run for a few minutes, can you crack open the tank cap and get a satisfying, yet scary, hiss of explosive gas fumes? (Don’t forget: The gas cap has to be screwed down tightly, for the system to build any pressure and be able to force fuel back up to the motor….) The check valve in the pick up would not be causing the problem you describe, I don’t think. It’s function is to work with the primer button. If it is stuck open, the primer button won’t pump fuel; although if you somehow were to get the engine started, it would pressurize the tank and stay running. If it is stuck closed, NO fuel will flow to the motor, either running or with the primer button.

For the record, I just recently went through the same pick up tube, check valve issue in a 4-gallon tank. I was able, with some twisting, to get the pick up assembly off of the steel tube, at least. I couldn’t get the valve itself apart, which was probably a good thing. With the tube off, at least I could get in at one side of the check valve, which is a small, wafer-type thing, not a ball. Some soaking with lacquer thinner and picking at it with a small tool, followed by blasts of compressed air, finally made it work right.

Long live American manufacturing!

• This reply was modified 3 years, 6 months ago by billw.
• This reply was modified 3 years, 6 months ago by billw.
• This reply was modified 3 years, 6 months ago by billw. Reason: clarification/wording

[Goman]

I didn’t check for air leaks around the glass filter on the motor last time maybe something there? The last 2 times I pulled the pick up tube out of the tank that little wafer thing would not rattle near as well when I first put it in sometimes not at all. Same thing the second time I pulled it. It’s my first pressure tank and may get a chance to look into it a little further this week.
Thank You
Glen

[frankr]

The glass bowl gasket got nothing to do with it. That is on the pressure side of the system, and the worst it can do is drip gas.
As bill said, if the pickup tube was stuck, it wouldn’t get gas to the motor, not even by pumping the primer button.
Can we assume the sintered filter in the glass bowl is not partially clogged, not allowing sufficient gas to pass through under normal pressure, but increasing the pressure by pumping the button thereby “fixes” it?

[billw]

Obviously, you have to be CAREFUL doing this; but the best way I know to check that valve (pardon the pun) is to take the tube off the main assembly, put it in your mouth and blow, then suck, on it. OKAY, NO GAS IN IT!!!!! I KNOW!!! Let’s not be stupid here. You shouldn’t be able to blow through it; but you should be able to suck through it. I still think your original posted problem doesn’t have anything to do with this check valve, though…

Long live American manufacturing!

[Goman]

Well I finally got back to it. I removed the fuel fitting on the motor and couldn’t even blow through the air tube part of it. The new hose to it had debris in it as well. It’s a ’58 Johnson 18hp in good shape and have no ideal how long it had been sitting till I got it running a couple of weeks ago. I guess that fuel fitting is something I need to tend to every now and again until all the debris works out of there. Thanks for the help guys it sure beats rebuilding pressure tank pick up tubes Ha!
Glen

[labrador-guy]

Obviously, you have to be CAREFUL doing this; but the best way I know to check that valve (pardon the pun) is to take the tube off the main assembly, put it in your mouth and blow, then suck, on it. OKAY, NO GAS IN IT!!!!! I KNOW!!!

Whatever you do don’t put a sparkplug in your ear! Kapluie!!
LOL

dale

[billw]

Today, there is a general tendency to overstate the seemingly obvious, in terms of safety. Did you ever look at a bottle of Tylenol or a can of spray paint? I just figured that if I DIDN’T say, or at least imply, ‘don’t suck gas into your mouth,’ somebody was going to call me on it.

Long live American manufacturing!

[Author]

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