corrosion in water passages

[tcurtsinger]

I was trying to do some repairs on my 78 115hp replacing water pump and thermostats. After getting the thermostat cover and valve body off in six pieces I noticed a lot of corrosion under the thermostats. There is also corrosion under the water pump. Is this normal on a motor this old and is there anything I can run thru the motor after its back together to flush it out? I haven't run the motor since I bought it three years ago, the previous owner ran it on muffs for me and told me it would overheat after a few minutes. He said he had a mechanic go over it and was told the thermostats were sticking. The pump looked good but the thermostats were corroded and didnt look like they would open. I now have a good boat to put the motor on and I am hoping to get it in the water soon.

 

[tashasdaddy]

Re: corrosion in water passages

well it has been sitting 3 years, so you need to do the water pump also. sounds like the motor was not properly flushed by a previous owner. you have to run the motor when flushing, until the tstats open. nothing to run thru to take away current corrosion.