....SOMEONE PLEASE HELP ME.1996 johnson 150 ocean runner fuel problem

[tobym333]

hey, i have a 1996 johnson 150 ocean runner . last night it started to sputter at full throttle . it seemed like it would get gas and speed up then bog down and then speed up and then bog down over and over until i got the boat back to the slip.. today i changed the fuel filter/ water sep. and the primer bulb... i pumped it until it got hard and started it and it ran excellent for about 4 minutes. then it died. when i pumped the bulb again it would start and i would choke it high and it would run for about 2 minutes then die. it wouldnt start again until i pumped the bulb ... please help me in this matter. i check the fuel lines and it seemed fine , a little old but other wise fine. this is my first boat.... please help. i know everyone reads and answers when they can and it gets old but please help me, i have no idea what im doing ...thanks in advance...

 

[d.boat]

Re: ....SOMEONE PLEASE HELP ME.1996 johnson 150 ocean runner fuel problem

be sure that the air vents in your tanks are open. If they're built in tanks, make sure the air vent is not blocked. There are other things, but that's first.

 

[tobym333]

Re: ....SOMEONE PLEASE HELP ME.1996 johnson 150 ocean runner fuel problem

this may sound like im crazy but where do i look to make sure it is vented? i looked under a portal hole in my deck and found where the plastic tank is.. is there a valve there ? or in the bilge pump area? what does the valve look like? thanks again for your prompt help i really really appreciate it..

 

[tobym333]

Re: ....SOMEONE PLEASE HELP ME.1996 johnson 150 ocean runner fuel problem

...

 

[Chris1956]

Re: ....SOMEONE PLEASE HELP ME.1996 johnson 150 ocean runner fuel problem

Fuel tank vent is thru hull and attached to the fuel tank via a hose, about 3/8" typically.

As a test, you may loosen the fuel tank cap to eliminate any non-venting (vacuum in the tank)concerns and retest.

 

[tobym333]

Re: ....SOMEONE PLEASE HELP ME.1996 johnson 150 ocean runner fuel problem

thanks, lets say that opening the fuel tank cap releases the pressure and it starts to work properly, how do i go about clearing the fuel tank vent hose? also what if the problem is the screen on the pickup in the fuel tank is getting clogged? i was told i can force air down the fuel line, is he talking about un hooking the line before the bulb and forcing air that way or the fuel tank entry where the gas goes? thanks again for your help...

 

[d.boat]

Re: ....SOMEONE PLEASE HELP ME.1996 johnson 150 ocean runner fuel problem

thanks, lets say that opening the fuel tank cap releases the pressure and it starts to work properly, how do i go about clearing the fuel tank vent hose? ...

Well, before getting into a lot of detailed hypotheticals, see if that works.

Then you'll have to find the air vent hose and how to clear it will probably be pretty obvious. There are probably two rubber hoses connected to your tank, one being fuel, the other vent. The fuel line obviously should be tracable back to the engine (maybe through a fuel filter cannister, etc.), and the air vent hose should be tracable to somewhere it goes through the hull or gunwale. The exit is usually protected or valved in some what so water can't splash into it.

If it's not clear to you, take some pictures of what you see. Maybe post a couple of photos of any hoses you see that connect to the tank and any fittings or hoses that go to connections that go through the hull.

... also what if the problem is the screen on the pickup in the fuel tank is getting clogged? i was told i can force air down the fuel line, is he talking about un hooking the line before the bulb and forcing air that way or the fuel tank entry where the gas goes? thanks again for your help...

Same thing with the fuel pickup filter - On my built in tanks it's obvious where the fuel line enters the tank, and how to remove it to inspect the pick up filter. But I dont' know about yours. Chances are if you can trace the fuel line to the tank, there will be an obvious connection point and that will be attached to a removable gasketed piece that holds the fuel pickup inside the tank. Hope that makes some sense.

Again, if it's not clear to you, just post some photos of what you see and go from there.

Good luck!

 

[tobym333]

Re: ....SOMEONE PLEASE HELP ME.1996 johnson 150 ocean runner fuel problem

i believe there is a exit vent right above my fuel entry on the side of the boat... i will check tonight, i think im also going to check the anti-siphon valve for any build up. what do you think? if something is in my vent hose how do i remove it??? do i force air through which would cause what ever is in the hose to blow back into the tank? or should i try and suck it out with a shop vac of some sort? thanks ... Semper Fi

 

[d.boat]

Re: ....SOMEONE PLEASE HELP ME.1996 johnson 150 ocean runner fuel problem

Here I'm on shaky ground because I've never had to clear a vent hose. But I would not blow it into the tank. Two reasons: of course you don't want to blow stuff into the tank. Plus, whatever is clogging it undoubtedly came from the outside and blowing from the outside in would force it in further, probably making it worse.

I have no idea if hooking a shop vac up to the vent hose is dangerous (sucking gas or vapors?... I really don't know, but I'd be cautious until someone credible told me it was safe).

My inclination would be to unhook the vent hose at the tank, put my shop vac on "blow" or use compressed air and blow it out the other way. Three reasons - the possible safety thing, the fact that you'd be blowing it out the way it came in, and I've found getting good blowing pressure is easier than getting a good seal for suction. I gotta think there's a way to access that vent hose at the tank and that's what I'd do.

Even if this isn't your problem (as I said in my first response, this is just a starting point, and the simplest solution), it's never a bad idea to make sure your vents are clear.

 

[tobym333]

Re: ....SOMEONE PLEASE HELP ME.1996 johnson 150 ocean runner fuel problem

thanks d.boat. im going to do all that and check my anti-siphon valve tonight and will post my results tomorrow morning.

 

[Scottycat]

Re: ....SOMEONE PLEASE HELP ME.1996 johnson 150 ocean runner fuel problem

NO SHOP VAC, could have explosive results.
I am willing to bet it's not his vent hose.

It may be his fuel pump or accumulated gunk it the float bowl, not allowing it to replenish at full throttle.

Check these after you look into the vent hose...

 

[tobym333]

Re: ....SOMEONE PLEASE HELP ME.1996 johnson 150 ocean runner fuel problem

well i went home and made sure the vent hose was clear. i pulled off the anti-siphon valve and it was corroded on the out side but clean as a whistle on the inside. i tried for the life of me to get the 90 degree fitting to come off but it would just spin with the large nut that is connected to the tank. i wanted to pull that off and look at the pick up tube screen. im picking up a new valve today and trying to get the elbow fitting off again but im not sure i can, we'll see.

 

[tobym333]

Re: ....SOMEONE PLEASE HELP ME.1996 johnson 150 ocean runner fuel problem

also last night before i took off the valve i started it up and about 2 minutes into it i started to hear a knocking sound. i immediately turned it off. whats next? should i turn it over to a mech.??? thanks in advance... .Semper Fi

 

[Ozerimar]

Re: ....SOMEONE PLEASE HELP ME.1996 johnson 150 ocean runner fuel problem

I would do a compression check if you have not already done so. You should be in the 100 to 110 range. The Knocking sound is not a good thing. You might of leaned out a cylinder because of a dirty plugged up carb. The carb is part of your lubrication along with the recirculation system. The carbs got to be set just right not too lean and not too rich.

 

[tobym333]

Re: ....SOMEONE PLEASE HELP ME.1996 johnson 150 ocean runner fuel problem

thank you for your advice. i am dropping it off to the local mechanic today . over the phone he said it sounded like the fuel pump but would know more tomorrow. i will keep everyone posted in case other people have the same symptoms ...

 

[Ozerimar]

Re: ....SOMEONE PLEASE HELP ME.1996 johnson 150 ocean runner fuel problem

smart move on your part and please post back with results.

 

[tobym333]

Re: ....SOMEONE PLEASE HELP ME.1996 johnson 150 ocean runner fuel problem

hey guys i wanted to give everyone an update on what the problem was on my boat. it turned out to be the pick up tube in the tank. the screen was clogged and the inside was corroded. i replaced the anti-syphon valve, the pick up tube, the fuel water sep. spark plugs and it is running like a champ... thanks for every ones help and advise.

 

[tobym333]

Re: ....SOMEONE PLEASE HELP ME.1996 johnson 150 ocean runner fuel problem

also the compression is checking from 110 to 116