Starboard Cylinders Running Hot

emdsapmgr

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Sometimes new stats are defective, too. Swap the stats and see if the heat problem moves to the other head.
 

Hennysemitara

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took off starboard hose lots of water, and cylinder started to run cool. but then port ran hot when hose was disconnected?
 

Hennysemitara

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took thermostats out put them on the stove they opened at about 160. what else issues could it be? i mean how can one side run way cooler then the other?
 

Fed

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Are you 100% sure both the bleed holes inside the thermostat housing are clear?

On initial start up the cold water has to be able to get out of each side of the thermostat housing so it can be replaced by hotter water from the engine, this hotter water opens each thermostat and once opened the flow is naturally maintained.

FWIW when my hoses are both disconnected the water flow and temperature at idle on muffs is equal from both hoses.
 

Hennysemitara

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Are you 100% sure both the bleed holes inside the thermostat housing are clear?

On initial start up the cold water has to be able to get out of each side of the thermostat housing so it can be replaced by hotter water from the engine, this hotter water opens each thermostat and once opened the flow is naturally maintained.

FWIW when my hoses are both disconnected the water flow and temperature at idle on muffs is equal from both hoses.
I took thermostats out. Both bleed holes are open. I will run the motor tommarow with both hoses disconnected. And see the temps. If they run at the same temp, what would be the problem the thermostat? They both open at the same time. Ill check for closing temps also.i dont know what else it could be.
 

emdsapmgr

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Each head should idle between 143 and 155. Once on plane, extra water flows thru the block and the head temps and go down as much as 20 degrees from idle temps. Possible the low temp stat may be stuck open.
 

Hennysemitara

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Ok guys so i started my boat with the hoses disconnected on both port and starboard side. the starboard was hotter then the port by about 10 degrees. water flow was even.
 

Hennysemitara

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Each head should idle between 143 and 155. Once on plane, extra water flows thru the block and the head temps and go down as much as 20 degrees from idle temps. Possible the low temp stat may be stuck open.

i checked the low temp side thermostat is not closed
 

Fed

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i checked the low temp side thermostat is not closed
Do you mean the low temp side thermostat is open when it should be closed?
That can't be good.
 

emdsapmgr

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That would make sense. If the thermostat is stuck open, then that side of the block will get lots of cooling water. The stat should open at 143. If it stuck open, it may never get to 143.
 

Hennysemitara

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That would make sense. If the thermostat is stuck open, then that side of the block will get lots of cooling water. The stat should open at 143. If it stuck open, it may never get to 143.

I ment that it was closed, i put them on the stove they opened at 160 degrees...
 

phillnjack2

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Get a magnifier and look on the thermostats, they should say 143, if not then get 2 genuine ones,

you asked what is the chance of 2 new stats being bad ? I have had 4 of them from the same batch being bad, they would not open even at 180c.
obviously I got my money back for the lot of them. I got these as a job lot thinking it was a bargain ha ha .
when you think about it there is less chance if you got 2 separate stats from different dealers, but from same batch they are liable to be both bad.
but it sounds like just one is bad, the low temp one is opening to soon.

Also did you change the relief springs ? new ones should be red in colour.
and when on the muffs do you get water coming out the two holes at the top of the mid section at idle ? if you do then its indication of stat opening too soon.

temp under 135 with infra red gun on top of cylinder block is far too low, that one side is opening too early or relief is stuck open !!!
 

Hennysemitara

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Get a magnifier and look on the thermostats, they should say 143, if not then get 2 genuine ones,

you asked what is the chance of 2 new stats being bad ? I have had 4 of them from the same batch being bad, they would not open even at 180c.
obviously I got my money back for the lot of them. I got these as a job lot thinking it was a bargain ha ha .
when you think about it there is less chance if you got 2 separate stats from different dealers, but from same batch they are liable to be both bad.
but it sounds like just one is bad, the low temp one is opening to soon.

Also did you change the relief springs ? new ones should be red in colour.
and when on the muffs do you get water coming out the two holes at the top of the mid section at idle ? if you do then its indication of stat opening too soon.

temp under 135 with infra red gun on top of cylinder block is far too low, that one side is opening too early or relief is stuck open !!!
They both say 143 on the copper part. I got a kit so it came with purple relief springs. I will try switch the thermostats around and see if that helps...
 

Hennysemitara

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So now my problem is one is too cool and one is too hot sheez cant seem to get it right šŸ˜”
 

phillnjack2

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you will get it right.
just go get a new thermostat, the one that is too cool is the bad one. I think this will cure your problem. ( I hope so )

just one more thing that can sometime cause over heating on one side of the omc v4. ( dont think this is your problem but worth a mention)
Look at the top of the block under the lifting eye, this little cover is the area that the water goes up to before going down into the heads.
I have seen on these before where an old piece of broken impeller has got lodged in one side hole and stopped the normal flow of water getting to the one
hot side of the engine.
it could also be a build up of limescale in there too ? just a thought , as this are is nearly always over looked when over heating troubles on the v4 occur.
its part number 43 on this diagram below.

http://www.marineengine.com/parts/j...rer=Evinrude&section=Cylinder+&+Crankcase

always worth remembering especially if an impeller has broken up and a bit is missing !!!!
 
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