Fuel Feed Problems

[MattBuss]

I could use similar help. I have been playing with mine for sometime, and it looks like the anti-siphon was not preventing the fuel from draining back into the tank. I changed the Anit-siphon valve, but still concerned what is the line is dry. My fuel pump does not come on with the key, but does come on with the ignition. Is there something wrong with my relay or one of the diodes?

4,3GL Volvo penta

 

[GA_Boater]

You should start your own thread.

Done.

 

[MattBuss]

Thank you BruceB. I tried starting a thread but I/m not that savvy. I have looked further into it, and have 13.97 volt when running, 10.97 vdc when starting. I think the anti-siphon valve was leaking fuel back into the tank so the pump was running dry. I have replaced the valve, and have an outboard primer bulb in line now for testing.

Question. If the line is dry, or not fully charged with duel, should the pump be strong enough to draw fuel to the carb?

Thank you

1999 Larson 186LXi
4.3GL Volvo Penta SX

 

[SeattleMatt]

MattBuss, it seems we have similar names, similar boats, with similar problems.

http://forums.iboats.com/forum/engi...ines-outdrives/10467370-fuel-pump-running-dry

Anyways, take the relay off (next to the pump on the housing) and try jumping the socket on pins 30 to 86 using a test wire with the ignition on (but not running).

See Don S's troubleshooting and diagram for assistance.

http://forums.iboats.com/forum/engi...nes-outdrives/561511-fuel-pump-relay-question

If the fuel pump runs, but sounds like it's not pumping fuel, then it might be same problem as mine.

Try topping off the filter to brim and spinning it back on.

 

[MattBuss]

Thank you. I have gone through the jumping exercise, and found that the pump (when line was dry) would run for a short while then stop. This led me to believe the pump was failing. Every Service tech I spoke to said they thought that if I was using a straight jumper, the pump would run without interruption until it burned up. I put a primer bulb in the line like you would see on an outboard set=up and ii purged the line with fuel. Once I did this, the pump started running continuously, and everything works fine. It will take time to see if my only problem was a leaking anti-siphon valve.
Now, I am wondering if the pump should be strong enough to dry fuel through a dry line, or if it just needed to be primed all this time.

 

[bruceb58]

The pump should be strong enough to pull fuel up to the carb and should never stop with voltage applied.. Sounds like you need a new pump.

 

[dypcdiver]

There is a non return valve in the primer bulb, which will substitute for the anti syphon valve if it has failed.

 

[SeattleMatt]

That's the same question I had, can the pump work through a dry line and get going, or does it need to be primed....

I like your inline primer bulb idea, I may do that, although I hate the thought of changing the configuration of the boat to hack a problem.

 

[bruceb58]

I like your inline primer bulb idea, I may do that, although I hate the thought of changing the configuration of the boat to hack a problem.

It's illegal to use a primer bulb in the bilge of any boat and which is why it is only used on outboards.

 

[Maclin]

Remove the primer bulb, it is against regulations stated in number (2) just below, has to do with how much fuel is allowed to leak from the "plumbing" after a catastrophic hose-severing event. Instead of the primer bulb, I would rig in a push button momentary switch that when you push it the fuel pump gets power to run while you are trying to debug, either in the driveway or as temp patch to get out on the water. Then if that works you can work on finding the problem in the supply side. Good luck, be safe!



FEDERAL LAW
183.558 - Hoses and connections
(b) Each hose used -

(1) For a vent line or fill line must be:

(i) "USCG Type A1" or "USCG Type A2"; or
(ii) "USCG Type B1" or "USCG Type B2" if no more than five ounces of fuel is discharged in 2-1/2 minutes when:

(A) The hose is severed at the point where maximum drainage of fuel would occur,
(B) The boat is in its static floating position, and
(C) The fuel system is filled to the capacity marked on the tank label under Sec. 183.514(b)(3).​

(2) From the fuel tank to the fuel inlet connection on the engine must be:

(i) "USCG Type A1"; or
(ii) "USCG Type B1" if no more than five ounces of fuel is discharged in 2-1/2 minutes when:

(A) The hose is severed at the point where maximum drainage of fuel would occur,
(B) The boat is in its static floating position, and
(C) The fuel system is filled to the capacity marked on the tank label under Sec. 183.514(b)(3).​

 

[dypcdiver]

Oh Boy, I was not advocating running with a primer bulb, I was pointing out that the non return in the primer would mask a faulty anti syphon valve. Please note in post Number 4 MattBuss states that he has a primer bulb in the line for testing.

 

[Maclin]

Oh Boy, I was not advocating running with a primer bulb, I was pointing out that the non return in the primer would mask a faulty anti syphon valve. Please note in post Number 4 MattBuss states that he has a primer bulb in the line for testing.

My posts were for the OP, we cool...

 

[SeattleMatt]

So is it likely this problem is the anti-siphon valve?