99 johnson 50 hp bogging down at full throttle

[jay s]

I have a Johnson 50 hp seahorse with a possible fuel problem. Took it out the other day and was running fine at full throttle for about 15 minutes when it started bogging down. Bogged down to about 5 mph (didn't go any faster) and acted like it was not getting fuel. Took it home and replaced the fuel filter (which had some dirt in it). Took it back out and it ran fine at full throttle for 10 minutes. Started bogging down again. Its idles rough and stalls out occasionally when put in gear (forward and reverse). But, it revs up to a high rpm when in nuetral. Could it be sucking dirt from the fuel tank or is it something else?

 

[Solittle]

Re: 99 johnson 50 hp bogging down at full throttle

jay - Looks liek time to rebuild the carbs. It is fairly easyalthough a shop manual helps. Here is some homework:<br /><br /> http://www.outboardrepairs.com/carburetors/

 

[clanton]

Re: 99 johnson 50 hp bogging down at full throttle

Some 2000 50hp models had problems with starter rubbing a hole in the VRO pump pulse hose, not sure what year or serial number this started, but I think it is worth checking. You have to remove the starter to get a good look at the hose.

 

[mzescamilla]

Re: 99 johnson 50 hp bogging down at full throttle

This seems like the same problem I was having with my 115 johnson. I would drive at full throttle and all of the sudden I would loose speed. I could not go faster than about 2 miles/hour. I redid the carbs and that did not help. I cant figure it out. I can run my boat full throttle out of the water, but as soon as i drop it in the bay, I have problems starting it...

 

[jay s]

Re: 99 johnson 50 hp bogging down at full throttle

Sounds similiar. Was reworking the carbs very tedious? I haven't worked on many outboards. I was thinking that I was getting trash into the fuel lines or something. I wanted to try to solve the problem myself before I took it to a mechanic. What is the VRO????

 

[clanton]

Re: 99 johnson 50 hp bogging down at full throttle

The VRO is a fuel pump/oil pump, the name has been changed to protect the innocent. I cant remember the name change. Seahorse give us the new name.

 

[Cricket Too]

Re: 99 johnson 50 hp bogging down at full throttle

Try running off a different, portable tank to see if it is a fuel problem. What is the temp. of the motor when this happens, maybe your running hot and the alarm is not working. Good Luck.

 

[jay s]

Re: 99 johnson 50 hp bogging down at full throttle

thanks to everyone for the advice. I'll try some of these ideas this weekend. Thanks again.