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25 johnson runs hot

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thumprj_11

New member
I am a new boater and not very

I am a new boater and not very familiar with outboard motors. I have a 1969 25hp johnson. The motor has sat for several years without use. I took it out on the water to test it out and I will need to do some work on this motor. The motor ran ok in the beginning and eventually just came to a screeching halt. We had to wait for an hour or so before motor started running again. It died again approaching the dock with the same screeching halt. A fellow fisherman offered the advice that I needed to check the motor cooler. He said I needed to replace it or check to see if it was clogged. I had no clue. Pls help!
 
"NOTE: The cavitation plate ju

"NOTE: The cavitation plate just above the propeller should be approximately 3/4" below the bottom of the boat at the transom. If it is inches above the bottom of the boat, then you have a short shaft engine installed on a long shaft transom. This will cause the water pump to be extremely high above the water level when the boat is under way. If this is the case, do not operate the engine.

Pam.... Always keep a eye on the hole that exists halfway down the exhaust housing (the housing between the powerhead and the lower unit). Water should really shoot out that hole with the exhaust when the engine is running at any speed.

The engine has overheated bad, causing the pistons to seize to the cylinder walls. Hopefully there has been no damage caused to the pistons and cylinder walls. A compression test will reveal their condition.

Be sure to check and tighten the powerhead bolts where needed (cyl head and side exhaust baffle plate area mostly).

You need to install a complete water pump kit, not just the impeller. This will most likely be available at your local NAPA store, also at any Evinrude/Johnson dealership at a higher cost.

Remove the lower unit by removing the small side plate that exists halfway down that exhaust housing, then remove just one of the 3/8" hex bolts that you see in the brass shift connector.

Now, remove the bolts that retain the lower unit to the exhaust housing. The lower unit should slide off, and the water pump location will be obvious."
 
Thank you for the advice. I w

Thank you for the advice. I will check out the motor and let ya know how it went. Thanks again for your help!
 
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