Logo
FULL SITE MENU

Running without thermostat

G

garzone

New member
Whats the thoughts on running

Whats the thoughts on running a '77 55hp Evinrude without the thermostat for "testing" purposes. Not continued use... Just trying to figure out if it may be getting too hot...
Any thoughts??

GZ
 
"Not a very good idea!!!
The

"Not a very good idea!!!
The thermostat is only a small part of the tepmerature regulating system, mainly at idle. At higher rpm, the pressure valve takes over, and removing the thermostat it will not work!!!"
 
"Thank you sir... I'll rem

"Thank you sir... I'll remove it and drop it in a pan of hot water then.....
"
 
"(Thermostat Purpose)

"(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"
 
"Makes sense... Thanks, I remo

"Makes sense... Thanks, I removed the thermostat, and it was not completely closed, and did not change when i put it into hot water... went from hot to cold / vice versa... no change. I will replace it today.

Please pardon my ignorance.... but...
**Should the thermostat be completely closed when cold, or is it normal for it to be open just a little bit?**"
 
"Never mind, answered my own q

"Never mind, answered my own question, bought a new thermostat, the old one was stuck open a little."
 
"Well, still running a little

"Well, still running a little hot...195F when it stalled...checked the impeller today...
time for a new one I guess...(guess this is common?)

287152.jpg
Impeller
 
Back
Top