No fuel to plugs

[Timlp]

1988 Force 50 HP. I am slowly figuring out this "new" boat, but not quite there yet. I have gas to fuel pump. From fuel pump to carb. I think I did a pretty good job cleaning the jet, but the gas flow appears to stop there. But what I don't know yet is does the gas to the plugs come by way of the carb?

In the pic below there is the line from the tank that goes to the fuel pump on the front right. The line on the front left goes to the carb. But I noticed a line on the back left that goes into what I guess would be the block? Is this what supplies the fuel to the plugs? That line was clear till where it connects, but I didn't remove it from the block and check inside.

Slowly getting frustrated, but pushing through

 

[Timlp]

Re: No fuel to plugs



Forgot the pic

 

[jerryjerry05]

Re: No fuel to plugs

Short hose is the puse hose that operates the fuel pump diaphram.
If you cleaned the carb and use almost any cleaner,it's possible you have swelled the o-ring in the seat.
Or it's not adjusted right
Tilt motor all the way up.Try to start while tilted.
Use choke and oh yea hook up the water.
Once it starts or coughs,lower and start.

 

[stubtail]

Re: No fuel to plugs

On a different note, how have you established that there is "no fuel to plugs"? Have you verified that you have spark? If indeed fuel is not getting where it needs to be, your float needle may be stuck closed. Some aftermarket needles have rubber seats that have been known to stick. Drop the float bowl to check it out.

 

[Jiggz]

Re: No fuel to plugs

One way to find out. drop the carb bowl and inspect the float for proper operation including the needle as mentioned by Stubtail. When you removed the bowl do not disassemble the float and needle system yet. Instead, test it with the primer bulb and you should see fuel coming into the bowl section through the needle valve.

If fuel flows then the needle valve is working properly, i.e. opens with the float in down position. While doing this, lift the float and see if the primer bulb will harden and stop the flow of fuel with moderate squeezing of the primer bulb. If the bulb hardens and fuel flow stops, then the float and needle valves are working properly.

However, there is setting required for the float which is horizontal, meaning fuel should stop flowing as soon as the float reaches horizontal position. If none of the above is working properly, then it's time to disassemble and inspect the needle valve seat. And by the way, do not forget to make sure the air screw is set properly, 1 turn out from lightly seated. If this air screw is shut or barely open, no idle air fuel mixture will get into the cylinder when starting the engine (assuming the throttle valves are idle or in neutral position).

 

[Timlp]

Re: No fuel to plugs

I did test the plugs and both of them have good spark. I assumed no fuel to the plugs. If you remove the plug wire and try to crank it, that plug should be a little wet or smell like gas, right? They were bone dry.

As for the float, the needle was definitely clogged or something. I wasn't getting any fuel in the bowl and consequently the carb when cranking. Thanks for the tip. I messed with that "several" times and now it is getting fuel in the carb when cranking. Did forget to adjust the air screw first couple of times. Adjusted that. Now it got a little closer to cranking, still hasn't turned the corner yet. Gonna take it to the lake in the morning and play a little more.

Slowly fixing things along the way and learning a lot about how it works thanks to you guys and a lot of taking it apart and putting it back together!! By the way, any tips for the next thing I should take apart or check out?

 

[Jiggz]

Re: No fuel to plugs

Taking it to the lake while it will not run on the driveway or muffs will not fix the problem. You need to make sure the engine starts and runs fine before taking it to the lake. If it won't start while on muffs, neither will it start while on the lake. Verify the air screw and set to 1 1/4 turn from lightly seated and make sure the idle screw is set properly. If you do not know what is a properly set idle screw, then just screw it on one full turn at a time until you get it started. When the engine starts then you can set it properly to around 1100 RPM in idle and neutral. And then set the air screw around 1 turn out from lightly seated.

 

[jerryjerry05]

Re: No fuel to plugs

Now if you have fuel to the plugs and a good spark.
It should fire.
Now that it's getting fuel(don't usually tell anyone to do this)a shot of starting fluid.
Just a little and don't over do it.It wipes the protective oil from the cylinder walls.

You using the fast idle?

Check for a sheared flywheel key??

 

[Timlp]

Re: No fuel to plugs

Couple of questions to be sure I am adjusting the right screws. And my float seems to work and then quit I bought a new needle today. Now I know the first problem is that the needle wasn't letting gas through to the bowl. I followed Jiggz advice and left the bowl off and hooked it up. I had to keep moving the float around to get gas to flow through, but it just seemed to flow for several seconds and I had to pump the primer and wiggle the float again. So the needle and the seat is still apparently not working properly.


The screw with the bolt on it toward the middle of the pic is the idle screw?


The screw on the top of the carb in the front is air adjustment screw??

 

[Jiggz]

Re: No fuel to plugs

The fuel will only flow through the needle when you prime the primer bulb which provides the fuel pressure to push fuel into the bowl. This is the function of the fuel pump when the engine is running. So when the float is in down position and you press the primer bulb the fuel gets into the bowl, this is the normal process. And then when you lift the float and press the primer bulb the fuel shouldn't go into the bowl while the primer bulb becomes hard. This is also a normal process. Of course, if you press really hard, the fuel can be forced into the needle.

The first picture is the idle screw which is different from the air screw which is shown on the 2nd pic. I'm not sure about the 3rd pic but looks like the choke rod connector or maybe the throttle valve rod connector. Anyways, no adjustment required on the screw shown on the 3rd pic. As soon as you get your engine started and running, I recommend you de-carbon it and see if this will improve its starting and running.

 

[jerryjerry05]

Re: No fuel to plugs

That screw in the 3rd pic is the jet,it should be open.
There is a jet in the bottom of the carb too.
Make sure it's not plugged.
If you can get it out without destroying it,clean it and make sure the passage behind it is open.
The air screw should be set at 1 turn out for initial starting.
If the needle isin't letting fuel in or operating right,then the float isin't adjusted right.
Have the manual?
Most show the carb set up.Even Seloc and Clymer show how to set the floats.
Don't use WD 40 unless your gonna use it as a protective coating(turns gummy and sticky.I use soap and water AFTER i use a carb cleaner.Then air to blow it dry.
Then right on the motor and then pump mit full with gas/oil mix.
The other cleaners and stuff can swell the rubber and stop it from working.

 

[Timlp]

Re: No fuel to plugs

Ok, I think I figured it out, but want to follow up on a couple of your suggestions to make sure I got those right.

On the pics I tried to erase the 3rd pic. I thought it was the air screw at first, but found out it was a jet. Thanks for the confirmations so I now know I'm adjusting the right things.

I did a check for the flywheel key without taking it off. Remove cylinder #1 and turn flywheel until piston is out at the furthest point. Then check if the timing marker is close to lined up. It seemed to be pretty close which would mean the key is good. Is this correct? I don't know what or where the fast idle is.

I also did an compression test and #1 was at 100 and #2 was 102. I tried a little shot of starter fluid... nothing!

Dumbfounded as to what it was, but I saw a test for the fuel pump. Remove the pump, but leave the fuel line connected to it. Pump the primer bulb and make sure the diaphragm doesn't leak. The diaphragm looked perfect, but when I pumped the primer it shot all over the ceiling! So if it is leaking that badly then the fuel is running into the back side of the pump and into... something that it's not supposed to. Would that maybe flood the plugs and cause it not to start? Surely it means less gas is getting to the float bowl and hence the carb. And I can just replace the diaphragm without replacing the whole pump, right?

Thank you guys so much for all the help. I would be utterly lost without this forum.