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CDMA
08-10-2000, 10:11 PM
I am having anothe problem on my boat. When I first put it in as I would accelerate as the secondaries would open the boat wouls stumble then go and after a couple hard passes just die. The fule bowl was just empty. So I looked around and found a loose connection on the vaccuum side of the fuel pump. The fuel pump is a brand new Carter Mougul. So after that there still was the stumble but I figured that was normal so I let it be. Well every so often this fuel starvation problem happens again. I am going along and the boat stutters and if I do not let off the gas it dies. Then I idle for a minute and go for 15 minutes fast and nothing runs like a champ. Can be a week before it happens again. I have checked all the fittings and they seem in order so what next?

Ideas?

Chris

PaulO
08-11-2000, 08:04 AM
Chris,
You need to check the fuel line the whole way including inside the tank. Pull the sender and pickup tube and make sure there are no restrictions and/or holes in the tube. If the problem only happens after a certain amount of fuel has been used, you may have a pinhole higher up on the pickup tube which is sucking air. I assume you have checked the pressure side also for restriction including the fuel filter(s).
PaulO

CDMA
08-11-2000, 08:29 AM
Paul,

When it happened yesterday it was with an absolute full tank. Had only used 3 or 4 minutes of fuel. I checked the fuel filters and even changed the big Racor I am running which is supposedly big enough for a BB. I also took a look at the little filter in the front of the carb and that seemed fine. The line from the fuel tank to the Racor is a Aeroquip aircraft grade hose with flare fittings professionally fit. From there goes a little hose clamped black hose, actually what came off your boat, to the fuel pump. Tha looked fine but I think I will change it any way. So I am at a little bit of a loss. I really only plan to use the boat for another month and then the engine comes out so I may just see if I can find an easy fix or leave it for now. I really am thinking about doing my tank this winter but I just am worried about damaging my paint.

Chris

RickSE
08-11-2000, 09:32 AM
The float level for your secondaries may be to low. Being low would not effect idle but you could be running out of fuel as you open it up and the secondary bowls empty. Also could be the needle and seat, they have a tendency to stick when engines sit unused, but they usually stick open.

PaulO
08-11-2000, 09:49 AM
Opps,
Just thought of something! Check the fuel tank vent. If the tank does not vent, it will create a vacuum. You can test it by running with the fuel cap loose or off.
PaulO

RickR
08-11-2000, 10:56 AM
The screen on your pickup tube may be getting debris sucked on it as you are moving. Then when you stop it falls off.

Also check valves on pickup tubes are notorious for causing problems.



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RICKR
mailto:riggerb@aol.comriggerb@aol.com</A>

CDMA
08-11-2000, 11:25 AM
Rick,

Ihave given a lot of thought to what you say about the pick up screen. The problem is the pick up fitting is welded in and can not come out as far as I can figure. That would account for the intermitedness as well as the fact I have to run for a few minutes hard flowing a lot of fuel to make it happen. I leave a week from today so I do not have the time to pull the tank but as we speak the fuel is being pulled out of the tank and run through a racor with a oil change pump I have that I fit with a gas impeller. I figure if I can get a lot of crap out with that and between running the boat and diluting the fuel the problem might just go away. If not out it comes and that 41 gallon tank Geoo put in goes in. I will keep you updated.

Chris

RickR
08-11-2000, 02:23 PM
Your tank should have baffels so work the siphon tube around if you can. Be very careful around all the gas http://www.donzi.net/ubb/eek.gifWhen you're under the bow wear your paint mask.

Check your vent tube also. Mud dobbers like gas vents.

BTW You can get alot of trash in your tank with portable 5 gallon jugs and a siphon tube. KEEP EM CLEAN!

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RICKR
mailto:riggerb@aol.comriggerb@aol.com</A>

[This message has been edited by RickR (edited 08-11-2000).]

Rob
08-11-2000, 03:38 PM
I hate to say this, but this sounds a lot like the problem I was having before I replaced my tank. Debris was clogging the pick up tube to such an extent that the carb would run out of fuel in extended WOT (or close) operation.

I also tried the pump it out and filter routine-with no success. If fact, I didn't know there was a special impeller for gasoline and almost had a bad fire. When I finally pulled the tank out, there was guk over an inch thick in the bottom. It took a high pressure car wash wand to knock it loose. Apparently the previous owner of the boat had filled up at a marina with rusted out storage tanks, and literally pumped the junk in.

If this is in fact the problem, you should be seeing traces of reddish brown material in your Racor. And if this does turn out to be the case, a potential short term solution would be to replace the pick up tube with a larger diameter one. The tube that comes with the original tank is suprisingly small. The larger tube likely pick up more debris as well, but your Racor will take care of that.