1999 Johnson 130hp fuel starvation issues?

thyNemesis

Seaman
Joined
Apr 19, 2013
Messages
73
I'm having some fuel delivery issues and I'm at a loss of where to starting looking again.

The boat had been running for quite sometime without issue. One day I ran out the channel, about 2.5 miles out or so, did some fishing and started to head back in. The motor started up and I ran for a few minutes up on plane, all of a sudden, engine started to die. I pumped up the fuel bulb and started the engine again, came up on plane for a few minutes and engine dies again. I had to do this over and over again all the way back in. However, while running the no-wake zone, about 15 minutes or so, boat would idle all the way back in without shutting down.

So far I have replaced the primer bulb, installed new fuel line from fuel pump all the way back to the water seperator with new clamps. New in-line fuel filter, replaced the Water seperator filter, installed a new check valve on top of the pick-up tube, blew out the pick-up tube with compressed air, 10-15 psi.

Any other ideas I'm missing? Am I in the right area, i.e. fuel supply, from tank to fuel pump?
Could it be my fuel pump? Any way to test the fuel pump prior to re-building it myself?

Thanks
Jeff
 

Bosunsmate

Admiral
Joined
Apr 7, 2012
Messages
6,135
Yes you a pointing your nose in the right direction,
sounds like fuel pump is going. To test it, when the engine starts dieing, quickly pump the prime ball again to act as a manual pump, if that fixes it its your pump.

You may also want to check its not an overheating issue.
Those pumps look expensive so will pay to diagnose properly.
Id run an electric pump myself instead of paying for a new one of them
 

Chris1956

Supreme Mariner
Joined
Mar 25, 2004
Messages
28,340
You may have an air leak at the main strainer, or one of the other fittings. Why do you have a water separator and an in-line filter? You do not need the in-line filter, and it will cause resistance to fuel flow. You did clean the main strainer, right? It has a seal. Is it sealing? Is the vapor pump working? Is the vapor separator sealing?
 

thyNemesis

Seaman
Joined
Apr 19, 2013
Messages
73
Chris,

The reason behind the in-line plastic filter is so I can quickly ID a fuel problem be looking at the clear in-line filter to verify fuel is present. I've run my boat for a year or so with it in use, never had a problem running.

As far as air leaks, I've replace all hoses and new band-clamps on all fittings from the fuel pump to the water seperator.

Main strainer, is this in the tank? I've tried soaking the pick-up tube fitting that is on the internal plastic fuel tank, very difficult to remove this. I don't want to crank to hard on this connector since it is attached to a plastic tank, I don't want to bust or rip off the fitting! Not sure how hard I can crank on this fitting!

vapor pump working? Is the vapor separator sealing? Not sure where look for this? I did, however, use 10-15 psi and blew into the pickup tube, right at the tank entry point of the pick-up tube. I have yet to take it back out since doing this procedure.

If my fuel pump is going bad, Bosumnsmate replied "He'd run an electric pump myself instead of paying for a new one of them." I looked at a fuel pump rebuild kit, $75 -vs- a auto electric fuel pump at around the same price. However, if I need a new pump > $400 or so, I would like to be able to convert to an external fuel pump, not sure how to do this convert, if posible.
 

Chris1956

Supreme Mariner
Joined
Mar 25, 2004
Messages
28,340
The main strainer is under the airbox, kinda in the center of the motor. It is a white knurled knob. The vapor separator is above the OMS pump, and the vapor pump is on top of the separator. It looks like a standard fuel pump.

Electric fuel pumps add danger to your boating experience. Unless you wire them through some kind of relay, that is run off some circuit that only has power when the motor is running (tach circuit or voltage regulator), they will always pump fuel when the ign is on. If the fuel line were to rupture when the ign is on (motor was running) the elec fuel pump would continue to pump fuel into the boat, and that is not good. I would recommend you stick with the mechanical fuel pump for safety.
 

thyNemesis

Seaman
Joined
Apr 19, 2013
Messages
73
During my troubleshooting session, When I removed my water separator filter, I noticed that the fuel level inside my water separator was about an inch below the center pick-up port.

When I was running my boat, it had died due to fuel starvation, I tried squeezing the bulb to see if I could keep the engine running but I noticed the primer bulb was collasped somewhat. It's like there was a negative vaccum preventing fuel flow. I thought it might be my fuel tank cap vent, so I opened the gas cap and the vaccum was still holding the primer bulb collasped.

This seem like the fuel is being restricted, flowing onto the water separator, just below the center pick-up post, fuel is being drawn off and once the fuel drops below the center pick-up port, the fuel syphon is broken and a vaccum is soon produced in the water serpator causing my fuel starvation problems?

Does this sound plausable?

I do have an external tank I will be running this weekend, trying to determine if it's my fuel pump or something back towards the fuel tank delivery system. I will also replace my water separator filter as well. It's (new filter) just started out the second season with it.
 

Chris1956

Supreme Mariner
Joined
Mar 25, 2004
Messages
28,340
If the primer bulb collapses, the restriction is upstream of it. It could be the antisiphon valve (usually screws into the fuel pickup on the fuel tank). It could be the first check valve in the primer bulb as well. I will assume you ruled out the tank vent, when you opened the fuel tank cap for a test.
 

thyNemesis

Seaman
Joined
Apr 19, 2013
Messages
73
It wasn't the pick-up tube anit-siphon valve, the fitting that was on there had no ball inside the fitting, although it looked as though a ball was there before. Anyhow, during my diagnosis phase, I remove and replaced all fuel hose and clamps from the fuel pump all the way back to the water separator. I installed new anti-siphon valve at the pick-up tube, blew shop air (10-15 psi) into the pickup tube, into the tank, sounded clean and un-obstructed. Used compressed air from the other end of the fuel line coming from the pick-up tube to the inlet side of the water separator, hose removed to verify a clear hose. New primer buld installed and checked for proper operation and orientation prior to installing (as before). I have yet to replace the water separator filter, yet.

I have rigged up a 5 gal external tank to eliminate the fuel pump side of things, will test this friday.
 
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thyNemesis

Seaman
Joined
Apr 19, 2013
Messages
73
Just got back from testing my fuel starvation problem.

I installed a new Water separator, ran it up on plane and shortly it died again. Dropped anchor and switched over to my external fuel tank. Ran back out the channel and made it all the way out this time!

So now I know that is NOT my fuel pump causing me all this grief but back towards the tank area. I only have to look at the fuel hose running from the water separator inlet back towards the tank anti-siphon valve(replaced already) and the pick-up tube(might need to replace) if I can lossen the connection to the plastic tank. It seems on there pretty well. I've been spraying it with a penetrating oil for a few days.

How hard can one crank on this pick-up tube fiting without doing damage to the plastic tank fitting?

I've almost got this problem solved!
 

HenryB

Petty Officer 1st Class
Joined
Dec 8, 2012
Messages
244
Replace the fuel line minus the check valve to make sure the stoppage is actually in the pickup assembly. Make sure the vent line is open. The vent line may be a duplicate of the pickup line and may have a tube and check valve with the tube extending into the gas. See if air or gas can be drawn from the vent tube and if air can/cannot be blown into the gas tank through the vent tube. With the vent line is clear and it’s determined a new pickup tube assembly is required (ugh!):

Say a prayer, if the metal pickup tube outlet fitting begins to twist (even the slightest) in the plastic tank, stop. Which way are you twisting the pickup tube elbo, clockwise or counnter clockwise?

Remove the sending unit. Siphon out the fuel. Flush the tank with water for at least two hours and keep the tank full of water.

Drill a hole using the proper hole cutter for a brass thru fitting close but not too close that will accept a new pickup tube. You should be able to touch the brass nut from the hole.

Get a cord and insert it through the new hole. Reach into the tank and retrieve the cord. Tie a block to keep the nut on the cord. You will find a brass through fitting, nut, and washer on line. Thread the outside cord through the fitting and draw the nut to the fitting and screw to tighten…well, leaving enough cord below the block for retrieval. Assemble a new pickup tube and the fuel sender to seal the tank. Plug the fuel outlet temporarily.

Plug the old pickup tube fitting.

With the boat on the trailer tip up the bow to get the water to the pickup tube and let stand overnight to make sure no leaks. Remove the sending unit and siphon the water as much as the siphon will draw. Vacuum the tank of remaining water and any debris. Replace the sending unit and cover the new pickup tube fitting all around with fuel proof epoxy.

Replace the check valve and fuel line.
 
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HenryB

Petty Officer 1st Class
Joined
Dec 8, 2012
Messages
244
I'd plug the pickup tube elbo to avoid damage in the event a new p/u tube is required.
 

thyNemesis

Seaman
Joined
Apr 19, 2013
Messages
73
I mananaged to remove the pickup tube elbow somwhat from the tank mounting flange, once removed I started to pull out the rubber hose attached to the aluminum elbow, once I got to the end of the hose it would not come out the hole, I think the screen is flared or something that prevents it from coming out all the way.

What if I were to cut the rubber hose as far down as I can on the old pick-up tube and let the end piece drop down into the tank and install a newer pickup tube in it's place. I don't thing that this small part will interfere with the new pickup tube operation, any concerns?

Thanks.
 

HenryB

Petty Officer 1st Class
Joined
Dec 8, 2012
Messages
244
It went in, you should be able to pull it out. Try a little harder. You’ve been very lucky so far. Cutting a piece off and letting it drop I don’t feel a problem. If you worry about it then drain and remove.
 

thyNemesis

Seaman
Joined
Apr 19, 2013
Messages
73
I've tried yanking on this pickup tube, will not come out no matter how hard I pull and twist this M' fer! I'm not sure what type of screen or filter is attached to the other end.

The fuel tank is a Moeller Model # FT-6003 or FT-6008 not sure of the last digit, very difficult to read. It holds 60 gals or 225lbs which doesn't calculate out properly, used 6.3lb/gal.

I'm waiting on Monday to call Moeller tech support about the pickup tube.
 

HenryB

Petty Officer 1st Class
Joined
Dec 8, 2012
Messages
244
Hopefully someone that experienced the same problem is reading this and can offer some advice. You might want to search this site for the problem. The situation is not uncommon.
 
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