Is this steam normal.. 1984 50hp Mercury

393Clevor

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I know it's a cold and nasty day and even my van is steaming pretty good.. New water pump has a good stream of water out of the telltale... seems like a lot of steam..

FF to 3.00 minutes

Video on the water
 
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racerone

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Looks like normal 2 stroke smoke to me.-----How did it run for you last season ?-----Or a new aquasition for you ?
 

393Clevor

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New to me this was it's first run.. I picked it up on a boat I bought for the aftermarket power trim unit.. The motor had a bad trigger I replaced it cleaned the carbs and put a water pump in it..
That's steam at 3 minutes into the video.. I don't remember any of my other boats steaming like that..
 

racerone

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Did not go to the 3 minutes till now.-----Best find out if it is running hot.----Is there an overheat sensor in the cylinder head?-----Can you hold your hand on the exhaust cover with motor at full throttle ?
 

393Clevor

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no sensor, hole has a plug in it.. and I could check the cover but I didn't.. water coming out of the telltale was hot but I could hold my hand in it.. So you think that's a little to much steam.. I thought so that's why I'm asking.. and where would one start to check for problems? pull the powerhead and check the passages for broken pieces of impeller.. Or??

I have another one,with the sender in the head, how does that work is it for a light or gauge?

Thanks..
 

Johnson110

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I hooked up a water pressure gauge, good to now how the water pressure is and if it gets clogged or not, could check with infrared gun at least give you and idea of how hot!
 

393Clevor

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That must be an alarm on the temp sensor so it would act like a switch.. maybe I'll test the sensor and see how it works.. biol it with a multi meter hooked to it and see how it reacts..
 

393Clevor

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I hooked up a water pressure gauge, good to now how the water pressure is and if it gets clogged or not, could check with infrared gun at least give you and idea of how hot!
I got one of those infrared guns somewhere.. I'll have to look, good idea.. not sure about water pressure though, what's a good number? Telltale blasts a good stream when the throttle it
 

Johnson110

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I think at idle 10 or 12 psi not sure, but when the pressure drops off you will know to shut it down to see whats going on!
 

393Clevor

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I think at idle 10 or 12 psi not sure, but when the pressure drops off you will know to shut it down to see whats going on!
wow, that's a lot.. most cars are only 15psi.. I don't think that's right but who knows that's why I ask questions.
 

racerone

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Why compare to a car.----The car has a pressurized cooling system.----The outboard floats / runs in it's cooling system with pressure to push water through it.----Lots of water to keep it cool at full throttle and load.
 

393Clevor

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Why compare to a car.----The car has a pressurized cooling system.----The outboard floats / runs in it's cooling system with pressure to push water through it.----Lots of water to keep it cool at full throttle and load.
he said it should have 10 to 12 psi.. pressure is pressure.. I think 10 to 12 is way to much, cars get there pressure from the water heating up in a close system.. I don't think an outboard would have but a few pounds if that at wot.. It's an open system and drains out as soon as you turn it off.. so.. the idea it might be low on pressure has nothing to do with it.. Moving on..
 
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Johnson110

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Yes totally wrong at idle should be more like 5 or 6 psi, as I said before you get a pretty good idea that something is wrong if the pressure numbers start going lower than what is normal.
 

racerone

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Instant experts .-----Some of you guys knows nothing about outboard cooling systems I say.------I like to see 25 PSI on my gauges at full throttle !!
 

BWR1953

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My 1985 50HP Mercury doesn't do that. :unsure:

Check at 0:54 seconds in.

 

393Clevor

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it's like freezing out here today like 50*, drizzly rain just nasty.. My van was steaming at the boat launch too.. I'll check temps in a few days.. go from there.. it was really cold and raw out today.. No sun shine that's for sure.. you can see the fog on the water..
 

393Clevor

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Instant experts .-----Some of you guys knows nothing about outboard cooling systems I say.------I like to see 25 PSI on my gauges at full throttle !!
you'd blow the telltale grommet right out of it..
 

Mark ofs

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I don`t know if normal or not, however I have a `85 35hp mercury, use to be my father-in-laws...I never recall it doing this, even when he was using it.
 

racerone

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25 PSI is a good pressure.----And no it does not blow the grommet.
 
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