Can't get gas to the engine!

[Gas Giant]

I apologize if this belongs in a specific engine section, but the problem here isn't my engine, its in my fuel lines/tank.

To start off, this is a boat that I have been working on and I have never used the in-floor gas tank before. I cleaned out it using some methods I found online.

I then ran a new fuel line from the tank to a new water separator I also installed. From there I ran a new fuel line with a primer bulb to the engine. The primer bulb is facing the right direction (after I first installed it in the WRONG direction....).

However, I can't seem to get any fuel to the engine, or even to the fuel separator. Squeeze away until your foreams looks like Popeye and you still have no fuel. So, I took the primer bulb fuel line off the fuel separator and tried it, and I had suction at the fuel line.

So I reinstalled that end, and took the fuel line off the other end of the fuel separator (the fuel line that runs from the separator to the gas tank). I checked for suction, and at the hose barb on the water separator I had suction - but the water separator and fuel line showed no evidence of having gas in them.

This is about as far as I got before I had to stop for the day. There isn't much left to check; but does anyone know why fuel wouldn't come out of the fuel tank even with suction? Tomorrow I'll check for blockage in the tank outlet, but other than that I'm lost.

Any advice would be appreciated! The boat is basically ready for a test run on the water (I was hoping to do that today, but oh well) if I can get this goofy fuel problem resolved.

And yes, it does have gas in it. 10 brand spanking new gallons I put in this morning. Thanks in advance!

 

[HT32BSX115]

Re: Can't get gas to the engine!

Howdy,


You probably have a "stuck" or plugged anti-siphon valve,

http://www.google.com/products/cata...og_result&ct=result&resnum=1&ved=0CCIQ8wIwAA#


or a plugged in-tank fuel screen or both!!

Try replacing the anti-siphon valve first....It should be installed in the fitting at the top of the tank or in an elbow fitting etc....... Be careful removing it, most of them are aluminum and will break if you "wrench" on them too hard!


Regards,


Rick

 

[Fireman431]

Re: Can't get gas to the engine!

1) Make sure the tank vent is working. If no air gets in, no fuel goes out.

2) Make sure the pick-up tube isn't clogged at the bottom with gunk or the filter screen isn't all fouled up.

3) Put the primer bulb on now and pump it to see if fuel is coming from the tank. If so, remove the primer bulb and put the line on the input side of your filter/separator.

4) Make sure the lines going to the fuel/water separator and going in/out on the proper barb or fitting. There should be directional arrows or, at least, labeled in/out.

5) Put the primer bulb on again and pump it until the filter is full and you get a good stream of fuel from the tank. Leave the bulb on here.

6) Attach the other section of fuel line that goes to the engine and complete your connections. Test run engine.

Possible causes for no fuel flow:
1) Tank pick up is clogged at the filter sock, pick-up tube, or tank vent clogged.
2) Fuel line has delaminated inside and it is collapsing on itself.
3) Bad primer bulb or primer bulb 1-way valve faulty.
4) Hoses on the wrong fittings at the filter.
5) Wrong filter

Besty of luck and keep us up to date.

 

[Bob's Garage]

Re: Can't get gas to the engine!

A couple other suggestion;

• Did you connect the fuel line to the proper connector on the tank - it should be the one at the opposite end from the filler hose. The fitting next to the filler hose is the vent fitting.
• Check your clamps at the fitting on the tank, you may be drawing in air.

If you are getting suction on the tank side of the filter, and it will stick to your finger when sucking, then you can reasonably expect that you have a good line. If it wont hold vacuum then you have a problem "upstream".

If all else fails you might try "priming" the filter with gas, reinstall, and then try pumping.

If the bulb doesn't re-inflate after being squeezed then you may have a problem down stream, as with a blocked vent system. If that is the case, open the gas cap (don't operate the engine with it open),and try again. If the bulb re-inflates then you do have a venting problem.

Remember that the pickup tube must be below the fuel level to draw gas, so if the boat is positioned so that the fuel is pulled away from the pickup, you cannot get any gas. Not likely but possible.

Good luck and let us know what you find.

 

[Bob's Garage]

Re: Can't get gas to the engine!

One other thing to check is to make sure the pickup tube is still good. If it was sitting dry for a long period it could well have corroded and either become "holed" or broke off

 

[Gas Giant]

Re: Can't get gas to the engine!

All great suggestions. I will check them out this week and report my findings. Thanks!

 

[Gas Giant]

Re: Can't get gas to the engine!

I managed to get gas flowing; the little check ball in the anti-siphon valve just needed a little nudge to break it free.

Now on to why it's so hard to start the darn thing!

 

[Fireman431]

Re: Can't get gas to the engine!

Choke working?

 

[Gas Giant]

Re: Can't get gas to the engine!

Yep, the choke is working. Its kind of a long story, but a short summary would be this:

1) It requires starting fluid at first; will fire right up and run with starting fluid - but not for too long. After the first fire up, it may or may not want starting fluid again to restart. Of course, it only runs for 10-20 seconds, but usually runs pretty well during that time until it loses power and dies. I attempted once to "feather" the throttle but either I did it wrong or it didn't work, because it still died.

2) Naturally, it requires you to close the choke during the first fire-up. After that, like the starting fluid, sometimes it wants the choke closed and sometimes it doesn't.

3) The primer bulb does get hard, but no matter what I can always squeeze it somewhat.

In short, I haven't learned the proper starting sequence for this engine yet, but nonetheless there is a problem somewhere since it only wants to run for 10-20 seconds. That is what I have to figure out.

Any suggestions? Fuel pump diaphragm, maybe? I do appreciate all the help so far.

 

[Gary H NC]

Re: Can't get gas to the engine!

I would replace the sticky anti-siphon valve.
What engine is this??

 

[Gas Giant]

Re: Can't get gas to the engine!

Suzuki DT75. I'll add that to my list of parts to replace. I don't seem to have trouble pulling gas from the tank anymore, but the fact that I can keep squeezing the primer bulb even after it hardens up worries me.

Unless that's normal.

 

[Fireman431]

Re: Can't get gas to the engine!

The primer bulb will never become so hard that you can't squeeze it. If you over pressurize it, you will screw up the one way valve that's in the bulb.

When you activate the choke (is it the ignition key style?), can you actually see or hear the choke engaging? Are you getting fuel to the carburetors? You can tell by removing one of the bowls or opening the drain screw on the bottom. Obviously, you have a fuel delivery problem if it will run on ether. Try cleaning the needle/seats and the low idle circuit screws.

Be careful with the starting fluid. Engines have been known to detonate internally with that stuff.

 

[Gas Giant]

Re: Can't get gas to the engine!

Ok, here is the latest:

Today, I replaced the fuel pump diaphragms, the fuel filter and the little rubber seal that goes with the fuel filter.

I also wrote down exactly what I did and what happened:

Attempt #1
-Used starting fluid and the choke was closed
-It started easily and ran smoothly for 15 seconds with the choke still closed.
-After 15 seconds, I opened the choke. The engine sped up, ran for another 5 seconds or so and died.

Attempt #2
-No starting fluid
-Choke closed
-It started easily and ran smoothly for 5 seconds with the choke still closed.
-After 5 seconds, I opened the choke. The engine sped up, ran for another 5 seconds or so and died.

Attempt #3
-No starting fluid
-Choke open
-Started easily and ran for 2-3 seconds and died

Attempt #4
-Used starting fluid.
-Choke closed
-Started easily and ran smoothly for a full minute with the choke closed.
-After 1 minute, I opened the choke. The engine sped up, ran for another 5 seconds or so and died.

Attempt #5
-No starting fluid
-Choke closed
-Started easily and ran smoothly for AT LEAST 3 minutes with the choke closed.
-Sometime between the 3 and 4 minute mark, I opened the choke. The engine sped up, ran for another 5 seconds or so and died.


The pattern, which is easy to see, is that when I open the choke the engine ultimately dies. When it was running with the choke closed, it was idling fast and strong - I should also note that I had the idle speed switch set to Fast Idle.

So what would cause this? Should I just let it idle for 10 minutes or so with the choke closed to let it warm up? I was told that I should be able to let up on the choke right after the engine starts.

Or is there something else wrong, that when the engine starts sucking in more air, it can't deliver enough fuel to compensate? Like I said, the fuel pump diaphragm and filter are both brand new.

Anyway, I appreciate your helping me with this wordy posts. Thanks so much, all of you. I love boating but I don't have a lot of money, so fixing everything I can by myself is a must.

 

[Bondo]

Re: Can't get gas to the engine!

So what would cause this?

Ayuh,... It sounds like the low speed circuit in the Carb is Plugged with Crud...

 

[Gas Giant]

Re: Can't get gas to the engine!

I was afraid of that - I take it there is no way to remedy that without removing the carbs. And I don't have a way to re-balance these things after I re-install them. D'oh!

 

[Gas Giant]

Re: Can't get gas to the engine!

I have the mechanic that rebuilt them doing it again; I will post the results for reference if anyone does a search in the future.

 

[BoatNoobie]

Re: Can't get gas to the engine!

I'm slightly confused because I'm a noobie. But on my old Merc 15 4S, there was a knob choke on the engine. I had to pull the choke out to start the motor. When I pulled it out, I thought this was "opening" the choke.

Right after the engine fires up, I push the choke back in, "closing" the choke.

Or do I have the opening and closing reference backwards. I dont know how the choke works or what it really does. I was told it either let in extra air or fuel to help with starting the engine.

 

[Bondo]

Re: Can't get gas to the engine!

Or do I have the opening and closing reference backwards.

Yes...

 

[NYBo]

Re: Can't get gas to the engine!

The frequent use of regular starting ether is bad for a 2-stroke- it contains no lubricating oil.

 

[Gas Giant]

Re: Can't get gas to the engine!

I'm using this starting fluid that has some form of lubrication in it; I got it at a marina and it says its safe for diesels and 2-strokes.

But I'm hoping that it'll start without it once I get it back.