High Maniflod temp on C-7

[Big Jay]

We have 3126's which i believe are the early version of your C-7's if i am not mistaken.

There's a LOT of zincs on those motors. You need to change them every season if not you will get some bad electrolysis in the cooling system. Get a freshwater flushing system that attaches to your intake strainers so you can flush out the cooling system after use.

To clean the exchanger go to your nearest sporting goods store and purchase a .22 LR cleaning brush and kit. You may need a bigger caliber depending on the size of the veins in the heat exchanger. That should take care of your problem

Your raw water impellers should be changed every 2 seasons no matter what.

[Questsportfishing]

new pumps installed and my hats off to the cat mechanics.. they cleaned up the engine room and did thier job very well.

[Big Jay]

I just do them myself every 2 years, really easy job. Not paying someone $1200 for something i can do in 3 hours and $120 in parts.

[Reveille75]

Big Jay:
Tell me more about the fresh water flush unit you mentioned. When I looked in the end of my intercoolers, I could see were the raw water had pooled up at the end. My boat is lift kept and is a little low at the back end so rain will run out the scuppers easily. A good flush every now and again might save some grief.
David

[Fortunamate]

well if your raw water cooled then you can get a sea strainer the has a valve at the top you open and then close you thru hull and it has a garden hose fitting on top and thread the hose on, start the enigne and turn the hose on and run it for like 5 to 10 minutes and big jay we also have the same engine 3126 great engine but i think we have like 11 zincs as you say and we change half of them every oil change and the scary thing is we need to change them