2000 johnson 50hp

[fa2685]

I have got a johnson 50hp, its starts and runs and show symptoms of overheating (won't throttle past idle speed) I replaced the water pump about a year ago, its got good flow, intakes are not plugged, ran good last week.
It is acting just like it did when pump went out before however it is not alarming and out flow is fine from hose...any thoughts??

 

[Silvertip]

Re: 2000 johnson 50hp

"Showing signs of overheating"??? What signs other than won't rev over 2000 RPM. If it is overheating the alarm should be sounding. Is it running on both cylinders? Does the overheat alarm sound when you first turn the key on? Can you hold you hand on the engine without immediately burning yourself. Need a little more to go on.

 

[ziemann]

Re: 2000 johnson 50hp

Help us to understand why you think it is overheating versus something else.

If you have good water flow it is not likely that it is over heating. Yes, it is possible that you have some sort of blockage in the water jacket and have a hot spot, but I would look look at the basic stuff first.

Look at the simple things first- fuel (carbs need rebuilding?), spark plugs? When were they last changed? Old fuel? (was it stabilized before storage?)

You get the idea...

Just because it ran last weeks, doesn't mean that there isn't a fouled plug this week, or some gunk in the carb...

 

[tashasdaddy]

Re: 2000 johnson 50hp

check your spark on both plugs, how old is the gas? 99% you have either lost spark on one plug, or have contaminated carbs.

Read the TOP SECRET FILE

 

[fa2685]

Re: 2000 johnson 50hp

little more info,
When started this weekend, it alarmed for about one second then stopped. It has not alarmed since when started or when running.
Will change plugs this week (rule that out), did pull the plugs, inspect, dryoff etc. this worked for about five minutes...
The fuel was not stabilized before winter, hoping not to rebuild carbs.
Anybody have a short cut to carb rebuild??

 

[tx1961whaler]

Re: 2000 johnson 50hp

Carb rebuild instructions in the "TOP SECRET FILE" post at the top of the forum.

 

[HybridMX6]

Re: 2000 johnson 50hp

The fuel was not stabilized before winter, hoping not to rebuild carbs.
Anybody have a short cut to carb rebuild??

How long ago was it stored for winter? With the gas these days with ethanol in it, it will start to go bad within a month. It will be worse if you have a pre-ethanol fuel tank, because the ethanol will start to break up deposits in the tank, then your motor will suck them in. Hopefully a filter catches them first.
I'd do as suggested so far, check spark, then clean the carbs. As for a short cut, just search for carb rebuild, Tasha has a good write up on it. If you meant a short cut on how to, there isn't one, just do it right and take your time, make you clean every little passage as TD says. It's not fun to have to take them all apart again b/c you got impatient and didn't clean it good enough.