motor running too cool? 1984 Johnson 140 2 stroke.

[interalian]

i use a lazer temp, i shoot all over the head ex. starboard base of sparkplug, port side base sparkplug, side of heads same areas port and starboard. i will try measure the water temp like you said. will keep you folks posted/

I wouldn't use the base of a spark plug for temperature as that area is not cooled directly by the water jacket. Typical places to measure are flat areas anywhere on the "figure 8" shaped cylinder head cover, or the top of the block just forward of the head gasket, or at the outlet hose casting on the heads.

 

[oldboat1]

Good idea to check and compare hose water temps, as suggested, but can't use an IR gun for that -- would shoot through the water and give you the temp of the surface underneath. Might try a meat thermometer for getting water temps.

 

[Hennysemitara]

I wouldn't use the base of a spark plug for temperature as that area is not cooled directly by the water jacket. Typical places to measure are flat areas anywhere on the "figure 8" shaped cylinder head cover, or the top of the block just forward of the head gasket, or at the outlet hose casting on the heads.

yes i shoot those areas too. same outcome tho there is a 20-30 degree temp diffrence. its funny tho i shoot the port hose its hot and the starboard hose is cool. wierd!!!

 

[interalian]

yes i shoot those areas too. same outcome tho there is a 20-30 degree temp diffrence. its funny tho i shoot the port hose its hot and the starboard hose is cool. wierd!!!

If you're measuring temperature on the hoses and the stbd hose is cool but the port side is hot, it means there's little to no water flowing through the stbd hose. The hose should be the hottest part of the entire cooling system as that's the water that started absorbing heat around the cylinders, then around the head, then around the head cover.

Points to blockage in the bleed holes in the thermostat plate as the water has to bleed past the thermostat in order to open it and let the water flow.

 

[Hennysemitara]

If you're measuring temperature on the hoses and the stbd hose is cool but the port side is hot, it means there's little to no water flowing through the stbd hose. The hose should be the hottest part of the entire cooling system as that's the water that started absorbing heat around the cylinders, then around the head, then around the head cover.

Points to blockage in the bleed holes in the thermostat plate as the water has to bleed past the thermostat in order to open it and let the water flow.

thermostat plate bleed holes are open, i disconnect the hoses and they both have water flowing.

 

[racerone]

So are all cylinders firing and at the correct time ?-----Have you test run out on the lake ?

 

[Hennysemitara]

So are all cylinders firing and at the correct time ?-----Have you test run out on the lake ?

hmm i dont know, maybe its off? sometimes it acts up dosent start, then starts. how would i know if it fires correctly? would that make one side run hotter?? that makes more sence cause i did EVERYTHING i could to the cooling system.

 

[Hennysemitara]

Merry Christmas Everyone!

 

[Fed]

Are you doing all this testing on the muffs, in a tub or in the real water?
If you're using muffs you may be under or oversupplying it with water.

 

[Hennysemitara]

Are you doing all this testing on the muffs, in a tub or in the real water?
If you're using muffs you may be under or oversupplying it with water.

Muffs and barrel

 

[interalian]

If you're running it in a barrel, how deep is the water? It needs to be about this high:

 

[racerone]

Do you have the same amount of water coming from both heads and one side is cool ??----That would suggest no heat produced on one side.---Check the plug wires ( orange )----You have to do the trouble shiooting.---I am not standing beside the motor.

 

[Hennysemitara]

If you're running it in a barrel, how deep is the water? It needs to be about this high:

uhm the water is literally right above the two intake holes on the bottom.

 

[Hennysemitara]

Do you have the same amount of water coming from both heads and one side is cool ??----That would suggest no heat produced on one side.---Check the plug wires ( orange )----You have to do the trouble shiooting.---I am not standing beside the motor.

yes same amount of water coming from both heads, plug wires are black,

 

[racerone]

??---No, no, We talk about the orange wires from powerpack to the coils !!----Start the motor and pull the black plug wires off one at a time on the cool side and report what happens

 

[interalian]

uhm the water is literally right above the two intake holes on the bottom.

Two holes? Not sure which holes you mean.

There are 4 holes on each side of the leg, just above the hub. These are the intake holes for the water pump, and are where you put the muffs to run on a garden hose, but when you're in a barrel, the water level needs to be higher than the pump assembly or it will not prime properly or quickly.

The 6 holes above the plate just above the prop are water exit holes.

The two holes up near the motor cover are exhaust relief holes.

Anyway, what racerone is trying to get you to do is a cylinder drop test to see if you're firing on all 4. The idea being any cylinder that isn't firing, also isn't creating heat and will make that area cooler.

 

[Hennysemitara]

??---No, no, We talk about the orange wires from powerpack to the coils !!----Start the motor and pull the black plug wires off one at a time on the cool side and report what happens

will do

 

[Hennysemitara]

Two holes? Not sure which holes you mean.

There are 4 holes on each side of the leg, just above the hub. These are the intake holes for the water pump, and are where you put the muffs to run on a garden hose, but when you're in a barrel, the water level needs to be higher than the pump assembly or it will not prime properly or quickly.

The 6 holes above the plate just above the prop are water exit holes.

The two holes up near the motor cover are exhaust relief holes.

Anyway, what racerone is trying to get you to do is a cylinder drop test to see if you're firing on all 4. The idea being any cylinder that isn't firing, also isn't creating heat and will make that area cooler.

the water pump intake holes im talking about right where you seperate the lower unit to access the water pump thats where the water line is on my bucket

 

[racerone]

Water MUST be 6 / 8" above the pump !

 

[Hennysemitara]

Water MUST be 6 / 8" above the pump !

but would that cause 1 side to be that diffrence in temp?