OX66 Fuel pump testing

[mlh1955]

Seen it before but couldn't find it in a search. How to check for leaks without having to disassemble the pumps and visually inspect diaphrams?

[DMSOUTH]

I assume you're referring to the lp pumps--best way is to loosen from engine, pump bulb and look for leaks. If you don't want to loosen from engine, pump bulb and see if it stays hard--if not, diaphragms are bad.

[mlh1955]

[Rich Z]

+1 Just ordered mine from boats.net. $34 each. All three of mine were leaking enough to cause the motor to shot down at high rmp. Now that was scary but everything else checked out fine.

[mlh1955]

Tested the pumps by taking the bolts out of the power head to loosen the pumps. Never did get any fuel to leak through the diaphragms. I've replaced the squeeze bulb in case it had a bad check valve, no change. It's still difficult to get the squeeze bulb to pump up and once you do it gets softer in a few minutes. I've noticed in the fuel filter canister that you can see the top fill with air slowly after the bulb is pumped up. seems like it is getting air from somewhere. Motor tends to be slower to fire up when the key is turned and smokes more on start up too . Any more ideas?

[bluegambler]

I dont think you need to pump the ball on a efi motor

[MeanGreenPathfinder22v]

I'm new to all this stuff, does anyone have any pictures of the testing of the diaphrams? I would like to give it a shot.

[JUST-IN-TIME]

yes u do, unless u want to replace the high pressure pump at 600

[mlh1955]

Never had to pump it before. Have any ideas on where to look next???

[Mat_HT]

Make sure you put some nuts on the back side of the bolts when you pull them off to check your pumps. They need to have pressure against them to work properly. And you will only find a leak if it is pulled tight like it is mounted on the block.
Also, you can burn up your electric pump by not using the primer bulb......over time they will just wear out from being over-worked.

[mlh1955]

Thanks Mat, I failed to place nuts on them to test. Nice to see you on the Low Performance side . Does the HP fuel pump have a check valve, if so could that be the problem if LP pumps test OK??

[Ryan G.]

So with EFI engine you are supposed to pump the bulb everytime you wanna crank the engine? I thought you only needed to do this for carbaurated motors.

[mlh1955]

You should rarely have to pump it unless you have a problem/leak somewhere or run out of fuel. Unfortunately I have a problem. I always check mine before I launch to make sure it is still pumped up just in case.

[dobber21]

take the two bolts out of the pump. dont take off the lines. there is a weep hole on the back of the pump. pump the bulb and if it leaks its bad. oh yeah pull the pump away from the motor so you can see it leak. see if that helps.

[mlh1955]

[JUST-IN-TIME]

you should always prime