Johnson 140hp only runs for a few seconds.

[fishincop]

Hello all,<br /> I just recently purchased a 17'6 venture fish n ski with a 140 hp johnson. The motor is a 1980 model 4 cylinder. I am fairly new to boat motors and this particular one has been sitting for about a year and a half. Previous to that, the owner put a new top half of the motor on it and ran it for about 8-10 hours then parked it, and it's been sitting ever since. My dilemma is this. . i hooked up the ears to it(water hose ears) and it'll run for a couple seconds then die. i changed the gas, gas line, gas fittings , and batteries of course. Is there anything else I need to do to this motor before i let it run for a while.. i want to make sure its going to run before i get out on a lake and leaves me stranded. Or if you can tell me anything else to check on it.<br />thanks for the help<br />Bill

 

[JB]

Re: Johnson 140hp only runs for a few seconds.

Hi Bill.<br /><br />Sounds like it is burning up the fuel you pumped into the carbs with the primer bulb, and it isn't getting more.<br /><br />That could be a problem with the fuel pickup in the tank, fuel lines, primer bulb, connectors or the fuel pump.<br /><br />After thoroughly checking the tank pickup and fuel lines for restriction or air leaks I would see if pumping the primer bulb would keep her running.<br /><br />If so, disconnect the line from the fuel pump to the carbs and turn her over to see if the fuel pump pumps strong spurts into a plastic bottle.<br /><br />If not, overhaul your fuel pump.<br /><br />Let us know what you find, and good luck.

 

[sailor_turned_stinkpotter]

Re: Johnson 140hp only runs for a few seconds.

After checking the above you should probably clean and or rebuild the carbs since theyve most likely got gunk in them from sitting so long. Ive heard some estimates that gas can start to varnish in as little as one month given the right conditions, and mixed gas is obviously even worse.<br />regards,<br />dave.

 

[fishincop]

Re: Johnson 140hp only runs for a few seconds.

Well today I changed the plugs. PUt new gas line, pump ball, and fittings..same thing. where is the fuel pump at? is it in the gas tank? also i noticed the starter gets hot after a few minutes of trying to start it. I think it might be bad but not sure. after it gets hot it drags a litte. Is there a good place to order a starter for it or a rebuild it? Also another stupid question. my wiring needs a little work. Im just wondering if there is wires going to the fuel pump if they are in the gas tank. there is wires coming from the gas tank but i thought they just worked the gas gauge.. sorry for sounding so stupid! <br />thanks again.

 

[skeets]

Re: Johnson 140hp only runs for a few seconds.

Hello Bill E<br />Do a search on no fuel to carbs<br />A lot of info there might be some answers.<br />LOL

 

[iRich]

Re: Johnson 140hp only runs for a few seconds.

Bill, You need to get a manual for your motor...try to get a factory manual if possible. The fuel pump is mounted on the block next to the carbs. I wouldn't go replacing stuff until you know the problem...<br /><br /> The starter will get hot after a few minutes...You should never crank it that long..<br />Rich

 

[fishincop]

Re: Johnson 140hp only runs for a few seconds.

I spoke to a local boat mechanic who was highly recommended. Ht said it's probably in the carbs. the previous owner just parked it and didnt drain the gas or anything. he said he would rebuild them for about a hundred bucks. is taht something i can do myself or not, i really don't feel comfortable with two carbs. one i might try but two i don't know. i ordered a manual today, should be in tuesday but if the carbs are easy to do i might try it.. depends on your feedback.<br />as always.. thanks