YAMAHA COOLING FLOW

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YAMAHA COOLING FLOW

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YAMAHA COOLING FLOW

Posted by JACK DARMON on June 04, 2003 at 17:38:00:

I WAS NEVER HAPPY WITH THE STREAM OF COOLING WATER FROM MY YAMAHA ENGINES SINCE
I BOUGHT MY BOAT USED. I JUST REMOVED BOTH THERMOSTATS AND FOUND BOTH OF THEM
COMPLETLY CLOGGED WITH SALT .I HAVE REPLACED BOTH.I WOULD RECCOMEND TO REPLACE
BOTH EVERY YEAR OR AT LEAST CHECK AND CLEAN THEM IF THE ENGINES ARE USED IN SALT
WATER. THE JOB IS SO EASY AND ONLY TAKES 10 MINUTES EACH THAT IT SHOULD BE PART
OF REGULAR MAINTANCE.

Follow Ups:

Re: YAMAHA COOLING FLOW Dan Hofmann 04:05:49 06/10/03 (0)

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Re: YAMAHA COOLING FLOW

Posted by Dan Hofmann on June 10, 2003 at 04:05:00:
In Reply to: YAMAHA COOLING FLOW posted by JACK DARMON on June 04, 2003 at
17:38:00:


Hate to tell you this but if your thermostat was clogged, your cylinder head
passages are probably worse yet. I just failed a head gasket in a 6 year old
engine. It was because the water was not going through one of the passages at
all. You may want to read some of the old notes here and flush your engines out

Pull off the two hose from the head while the engine is running and make sure
you are getting good flow there

I had a valve problem in the other engine 2 years ago and saw the build up in
that one when I examined it. Removing a head and doing the valves is pretty easy
so I have decided to do that as a preventative fix after 4 years.
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