50 h.p force will not run

I have a 50h.p force outboard that all of a sudden slowed way down on the lake to a slow idle and then could not get it to run ever since. the motor cranks and sputters like it wants to fire but just wont. I took the carb apart and cleaned it and replaced the plugs once again. The motor gives me signs of life but I dunno what other step to take. Please help ser. 508f90d

Re: 50 h.p force will not run

Start by checking for spark, and compression, on both cylinders.

Re: 50 h.p force will not run

What Roscoe said....
Then, to check for fuel delivery problem, spray a mist of fuel directly into the carb. Watch out for overspray outside of the throat of the carb, (will ignite if it comes in contact with any spark), but use an old spray bottle if you have one. Another trick just to check for a fuel problem is one of those small butane refills. Shoot a blast of it into the carb.
If you get a good sputter or temporary startup out of the deal, you know it's fuel delivery... We can't rule-out a compression problem, or clogged exaust if this test is sucessful, just ignition -- because compression creates the vacuum required to operate the fuel pump, and to draw fuel into the carb -- Clogged exaust, and the engine cannot exhale.
Lettuce know what happens.

Re: 50 h.p force will not run

Wow, I am having the EXACT same problem. I ran the boat maybe a mile and noticed the boat slowing down. I slowed to idle and the boat motor sounded strange so I shut it off. A burning smell and smoke came from the engine. The engine was VERY HOT. I let it cool for an hour and then tried to restart it. It would turn over but not start. The only way to get it to start was manually push the trottle way up on the carb. It would start and run but when you got close to idle it would die. I never noticed if water was coming out of the exaust before I shut it down. When I wass able to get it to run but throttling it way up I did see a little water coming out. Today I pulled the lower unit off and the impeller looks fine. There was some milky build up around the waterpump housing but I'm not sure that really matters. I drained the oil from lower unit and it was dark and smelt a little burnt, but wasn't milky and I couldn't feel any metal flakes. I've had someone check the compression and it read about 90. He thinks it should be around 100-110 but since both were around 90 he feels it's okay.

Any suggestions on what to check next?

Re: 50 h.p force will not run

Can I join your club here? I have a 50hp also 1999. (Not sure of the model number). Thought it was flooded, but had to be towed. A tech I called yesterday said to check the kill switch. I don't even think I have one, but I pulled the yellow/black wire that should be kill switch, and it didn't start. Today, I pulled the fuel line and tried to start and it started after about 30 secs of turning. ran until fuel was out. Reconnected and it started right up until I noticed fuel leaking again and then it died. Repeated the first success again and pulled the carb. There was something sticky on the float. I wiped it off and reinstalled it. It started, but then the leaking began and death once again. I got it started with the fuel line off again and then connected the fuel line and throttled it, and it maintained. Put it back to idle and the leaking begins and it starts to die again until I throttle it. Could my idle be set too low? If so, how do you adjust it? There is only one screw on top of the carb that I saw.

Re: 50 h.p force will not run

Well could we get a couple more posts added here.
Cosmo it sounds like your float or float valve is sticking or not closing for some reason.
Foe sounds like a major overheat that slowing was the motor seizing up.
If your lucky you may just need to change the head gasket.Check the compression.From your discription I would pull the head and check for damage.Cylinder scoring etc.
Of course check the impeller and thermostat.
Now you'll get better results if you post your questions seperately..

Re: 50 h.p force will not run

foe2379 said:

Wow, I am having the EXACT same problem. I ran the boat maybe a mile and noticed the boat slowing down. I slowed to idle and the boat motor sounded strange so I shut it off. A burning smell and smoke came from the engine. The engine was VERY HOT. I let it cool for an hour and then tried to restart it. It would turn over but not start. The only way to get it to start was manually push the trottle way up on the carb. It would start and run but when you got close to idle it would die. I never noticed if water was coming out of the exaust before I shut it down. When I wass able to get it to run but throttling it way up I did see a little water coming out. Today I pulled the lower unit off and the impeller looks fine. There was some milky build up around the waterpump housing but I'm not sure that really matters. I drained the oil from lower unit and it was dark and smelt a little burnt, but wasn't milky and I couldn't feel any metal flakes. I've had someone check the compression and it read about 90. He thinks it should be around 100-110 but since both were around 90 he feels it's okay.
Any suggestions on what to check next?

Click to expand...

90 lbs is NOT OK !!! You have a serious engine problem. On a 50 hp, compression should be around 135-145. I tested mine yesterday and it was 135 on both cylinders. The burning smell was your engine overheating. The lack of compression is probably caused by weak rings or scuffed cylinders. The impeller may have looked OK, but obviously wasn't. A water pump should be serviced ever season.