2004 Honda 40HP 4-stroke - no water circulating


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Jul 31, 2022
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Rescue Ca
Hi all, I went to look at a boat yesterday that has a 2004 Honda 40HP 4-stroke.
The motor was started and ran fine with a water hose attached. Noticed that there wasn't any water "peeing" out.
The cowling also has paint bubbles and possible heat related damage.
The current owner says that water wont circulate until the motor hits a certain temperature.

I am relatively new to boats but I thought outboards always circulated water regardless of the temperature of the motor.

Is this guy trying to sell me a damaged motor ?
I just bought a 2005 Tracker with a 60HP Merc. It would not pee when hooked to a hose with muffs but circulated fine once in the water.
Strange that there is evidence of heat on the cowling. Suspicious I would be without putting in the water.
Started and run a ton of Yamaha 4 strokes. They start flowing from the indicator as soon as the block fills not when the thermostat opens.
One easy check though is to put a toothpick or wire up into the indicator nozzle and clear it. If the pump is good it should start pumping at this point.
Secondly.....if he is running it on a set of muffs that are square or rectangular instead of round it probably will not pick up water as readily as the good round ones.
Burned paint around the cylinder head is never a good thing. Is this where the block/head shows paint damage or on the cowling. If it is the cowling there may have been an electrical fire under the hood. Check all wiring. Ask for receipts for work performed. Ask if the engine has ever been serviced, do a compression check, etc.......
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My Honda 50 (much newer 2018 model) starts peeing right away. Mine has a third water intake under the cav plate. When running on muffs, put a piece of duct tape over that intake. Also I wonder if the guy was simply not turning the hose on enough.

There could be a legit reason like Pappy says. Guy should know. If he tries to say it is normal, I would be very suspicious of that motor.

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