Fuel Ball Collapsing

L'attitude · 07-06-2012, 02:16 PM

I am posting because this problem has been plaguing me for over a year. I have a 25' Gradey White with twin Yamaha 200's and with 2 fuel takes, and 110 gal main, and 90 gal aux. From the each fuel tank, there are two lines that run to a switch, than separate lines out of each switch to each engine. Each line to engine has its own water separator and primer ball. There is one vent line per tank. The fitting for the fuel tanks do not have any anti-siphon valve that I can tell.

When running at cruise of about 4500RPMS, the primer ball will collapse until you switch over to the main tank. It will do with either engine, it will allows follow the aux tank.

I have changed all the fuel lines from both tanks all the way to the engine including primer balls and filters. I've taken the switch about and there is nothing clogged in it. I have changed both vent lines. I have blown out the vent lines to make sure fuel is not clogging them, which no fuel in vent lines. I've also had emerald coast marine completely clean out both tanks and remove any build up.

PLEASE HELP! This annoying problem nags at me every time we take the boat out. Plus, it limits distance on offshore strips.

Ocean Master · 07-06-2012, 02:27 PM

To help with diagnosis, and if you have clean fuel, I would attach the fuel lines directly to the engines. By passing the fuel/water separator. Just to see if it still collapses the primer bulb.

Are your primer bulbs before or after the separator?

L'attitude · 07-06-2012, 03:26 PM

Thanks for your reply!

The primer balls are after the water seperators. There is a seperate one for each engine and the ball collapsed with either one

aroundthehorn · 07-06-2012, 03:44 PM

Quote:

Originally Posted by Ocean Master

To help with diagnosis, and if you have clean fuel, I would attach the fuel lines directly to the engines. By passing the fuel/water separator. Just to see if it still collapses the primer bulb.

Are your primer bulbs before or after the separator?

This is good advice. Remember, too, that the bulbs can malfunction at any time. Something that it's hard to remember to check.

ctilton · 07-06-2012, 04:05 PM

Quote:

Originally Posted by aroundthehorn

This is good advice. Remember, too, that the bulbs can malfunction at any time. Something that it's hard to remember to check.

2nd the good advice, some times going through the fuel water seperator is too hard of a vacum to pull fuel and the bulb is weaker than the walls of the fuel line so it collapses.

Valhalla · 07-06-2012, 04:18 PM

If i am reading your symptoms right there is nothing wrong with your primer bulbs, seperators or fuel lines. If this was the case your problem would occur when running off your main tank as well as your aux tank. Is your fuel line coming from your aux tank the same size as the one coming from the main? smaller diameter hose could collapse your bulb as engine demand increases, you mention switching from main tank to aux, is this an electrical switch or mechanical? maybe it is not opening fully thus limiting fuel flow? what about the hose/fittings coming out of the aux tank? same size as the main tank, just a small difference from a 3/8 to a 1/2 inch can make a big difference. what ever it is it sounds like something is restricting your flow in your aux tank plumbing before the switch assy -after that the main and aux share components and plumbing. good luck and let us know what you find, always good to learn from each other

abacodan · 07-06-2012, 04:24 PM

I would also check the air vent outlets. On our old Grady White, circa 1982, this issue arose from two things, one of which you probably have already cured, that was the micron filter on the pick up in the tank being gummed up, the second was the metal screen they had in the outboard end of the air vent line had corroded to the point of restricting air flow, which led to air and fuel restriction, collapsing bulb.

L'attitude · 07-06-2012, 07:44 PM

I have replaced all the fuel lines and they are all the same 1/2". I also changed the vent lines. There are no screens at the vent at the side of the hull.

The pickup is the tub that goes to the bottom of the tank below where the fuel lines connect? That is the only area that I have not touched yet. Are those removal? I haven't been able to tell. Or can they be cleaned with compressed air?

Sequoiha · 07-06-2012, 08:06 PM

ill be honest with you about your choice of fuel line, you just posted you replaced everything with 1/2 inch fuel line, this is not always good, depending on the length of the run and if there are any dips or climbs in the line. the bigger fuel line holds more fuel thus takes more suction to pull it threw. your lift pumps are only designed to pull 4.5 hgs, any more than that is considered a restricition. if you had some 350 4 strokes then the 1/2 " fuel line is appropriate. for your application you need 5/16" fuel line. just a thought, and im assuming the main tank is closer to the front, or further from the engines. just a thought

L'attitude · 07-06-2012, 08:20 PM

Kenny, thanks for your reply. I replaced the lines with the same as was in there, and fairly certain the ones I replaced were original. I don't know if you remember the boat, you flushed the tanks in winter, it's an '89. I just don't what else to look at except replacing the fuel tank itself?

07-06-2012, 02:16 PM	#1
L'attitude Junior Member Cigar Minnow Join Date: Jul 2011 Posts: 9	Fuel Ball Collapsing I am posting because this problem has been plaguing me for over a year. I have a 25' Gradey White with twin Yamaha 200's and with 2 fuel takes, and 110 gal main, and 90 gal aux. From the each fuel tank, there are two lines that run to a switch, than separate lines out of each switch to each engine. Each line to engine has its own water separator and primer ball. There is one vent line per tank. The fitting for the fuel tanks do not have any anti-siphon valve that I can tell. When running at cruise of about 4500RPMS, the primer ball will collapse until you switch over to the main tank. It will do with either engine, it will allows follow the aux tank. I have changed all the fuel lines from both tanks all the way to the engine including primer balls and filters. I've taken the switch about and there is nothing clogged in it. I have changed both vent lines. I have blown out the vent lines to make sure fuel is not clogging them, which no fuel in vent lines. I've also had emerald coast marine completely clean out both tanks and remove any build up. PLEASE HELP! This annoying problem nags at me every time we take the boat out. Plus, it limits distance on offshore strips.

07-06-2012, 02:27 PM	#2
Ocean Master Senior Member Sailfish Join Date: May 2008 Location: Gulf Breeze Intercoastal Posts: 2,090	To help with diagnosis, and if you have clean fuel, I would attach the fuel lines directly to the engines. By passing the fuel/water separator. Just to see if it still collapses the primer bulb. Are your primer bulbs before or after the separator? __________________ "How I Roll" On channel 68 "Wheelchair Accessible Fishing"

07-06-2012, 04:18 PM	#6
Valhalla Senior Member Mingo Join Date: Dec 2008 Location: Pensacola Posts: 143	If i am reading your symptoms right there is nothing wrong with your primer bulbs, seperators or fuel lines. If this was the case your problem would occur when running off your main tank as well as your aux tank. Is your fuel line coming from your aux tank the same size as the one coming from the main? smaller diameter hose could collapse your bulb as engine demand increases, you mention switching from main tank to aux, is this an electrical switch or mechanical? maybe it is not opening fully thus limiting fuel flow? what about the hose/fittings coming out of the aux tank? same size as the main tank, just a small difference from a 3/8 to a 1/2 inch can make a big difference. what ever it is it sounds like something is restricting your flow in your aux tank plumbing before the switch assy -after that the main and aux share components and plumbing. good luck and let us know what you find, always good to learn from each other Last edited by Valhalla; 07-06-2012 at 04:24 PM.

07-06-2012, 08:06 PM	#9
Sequoiha Senior Member White Marlin Join Date: Sep 2007 Location: Orange Beach Al. Posts: 2,970	ill be honest with you about your choice of fuel line, you just posted you replaced everything with 1/2 inch fuel line, this is not always good, depending on the length of the run and if there are any dips or climbs in the line. the bigger fuel line holds more fuel thus takes more suction to pull it threw. your lift pumps are only designed to pull 4.5 hgs, any more than that is considered a restricition. if you had some 350 4 strokes then the 1/2 " fuel line is appropriate. for your application you need 5/16" fuel line. just a thought, and im assuming the main tank is closer to the front, or further from the engines. just a thought __________________ Kenny Mann Ms Penny Fishing Team Member NRA 172499461 Barber Marina 1-251-987-2628 (BOAT) www.barbermarina.com Sequoiha@mediacombb.net

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07-06-2012, 03:26 PM	#3
L'attitude Junior Member Cigar Minnow Join Date: Jul 2011 Posts: 9	Thanks for your reply! The primer balls are after the water seperators. There is a seperate one for each engine and the ball collapsed with either one

07-06-2012, 04:24 PM	#7
abacodan Junior Member Ruby Red Lip Join Date: May 2008 Posts: 29	I would also check the air vent outlets. On our old Grady White, circa 1982, this issue arose from two things, one of which you probably have already cured, that was the micron filter on the pick up in the tank being gummed up, the second was the metal screen they had in the outboard end of the air vent line had corroded to the point of restricting air flow, which led to air and fuel restriction, collapsing bulb.

07-06-2012, 07:44 PM	#8
L'attitude Junior Member Cigar Minnow Join Date: Jul 2011 Posts: 9	I have replaced all the fuel lines and they are all the same 1/2". I also changed the vent lines. There are no screens at the vent at the side of the hull. The pickup is the tub that goes to the bottom of the tank below where the fuel lines connect? That is the only area that I have not touched yet. Are those removal? I haven't been able to tell. Or can they be cleaned with compressed air?

07-06-2012, 08:20 PM	#10
L'attitude Junior Member Cigar Minnow Join Date: Jul 2011 Posts: 9	Kenny, thanks for your reply. I replaced the lines with the same as was in there, and fairly certain the ones I replaced were original. I don't know if you remember the boat, you flushed the tanks in winter, it's an '89. I just don't what else to look at except replacing the fuel tank itself?

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