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Cooling for a 86 120

S

scubadoo

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theromostats were melted this

theromostats were melted this morning when it over heated checked impeller and can't see any damage there
question 1:
after removing the melted thermostats reattached the housing cover I still don't have any water cooling the motor
question 2:
can I run the motor without the thermostats in
 
"Install a complete new water

"Install a complete new water pump kit (everything).

Thermostats are required, see below.

(Thermostat Purpose)
(J. Reeves)

Many engines are considered high performance engines and demand a thermostat(s), and many smaller hp engines also require a thermostat for the following reason. The pistons actually distort/twist off round when running. The thermostat is required to keep the outer wall surrounding the steel cylinder, and the cylinder wall itself at a temperture to compensate for the distortion.

With the thermostat removed, the difference in temperture between the inside the cylinder and the water jacket quickly reaches a point whereas (in effect) you have a oblong piston running up and down a round cylinder, or vice versa. Bottom line is without the thermostat, the piston and cylinder wall could be damaged in a short period of time.

The thermostat in your car isn't there simply to have the heater function properly..... think about it.

Thousands of parts in my remaining stock. Not able to list them all. Let me know what you need and I'll look it up for you. Visit my eBay store at:

http://stores.ebay.com/Evinrude-Johnson-Outboard-Parts-etc?refid=store"
 
this is a new water pump kit w

this is a new water pump kit what I have found is the impellar turns (when turning manually) but as soon as there is any pressure on the impellar you can feel it skip and then it doesn't catch any more
there were 2 plastic pie pieces that came in the kit the smaller of the 2 is the one that fits the larger there is no way it fits way too big
 
"Therein lies your problem. Th

"Therein lies your problem. That impeller does require a fairly large plastic/nylon key. With the driveshaft flat spot facing you the thin tapered end of that key faces left.

When installed as it should be, it is impossible for the impeller to slip past that plastic/nylon key."
 
"If You have run the engine at

"If You have run the engine at a temp where the thermostats have melted, double check the large rubber seal between exhaust and lower unit and replace if damaged. Otherwise You risk exhaust entering the pump."
 
Update
lower unit back toget

Update
lower unit back together just waiting for the new thermostats to come in then comes the water test.
I got very lucky the only damage was the thermostats
 
"morten...how do u figure,..ex

"morten...how do u figure,..exhaust,gets into the WATER PUMP,.from a bad exhaust seal....i have seen u post this,over and over....the last tech update,i had,of many,..never insisted on that seal...the wtr pump,is enclosed....i have actually,left out,..that exhaust extension,by accident,over the yrs,..and never saw a prob....that seal,in my opinion,and brp's-----is for exhaust exit only-----ur response,..i actively..await!!"
 
"Running at 'full' spe

"Running at 'full' speed the exhaust pressure and temp is rather high. The seal missing/damaged, You get exhaust at temps of far above 200 C going straight at the water pump. It does not take too long until the upper seal, O-ring and impeller gets 'damaged' with a considerably shortened life time due to premature wear. The leakage normally appear where the driveshaft goes through the pump-housing causing pressure loss or even exhaust entering the pump. As You say: --is for exhaust exit only--, meaning getting the exhaust out where it is supposed to go, and not somewhere else where it may cause damage!"
 
"i agree,..damage,..could,...p

"i agree,..damage,..could,...possibly happen...i have seen it on I/O's many times....never on an outboard....but,..i def agree about the heat factor...buut,...have seen them come in,w/exhaust tube missing,...evidently,..for yrs....heat,is ONE thing,...exhaust entering water pump hsng,under discharge pressure,even around the d-shaft...........aint gonna happen............in texas!.....melt down of wtr pump hsg,poss in etecs,...as i read...or di's...etc's........they r burning up everything, south of the pwrhd,...that is not ALUMINUM..."
 
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