1988 evinrude 20hp excessive moisture coming from exhaust

[Rodrider]

I have excessive moisture (more so than usual coming out the exhaust and the alarm sounds after a few minutes
The impeller is working fine( as in there is a stream of water come out like it is supposed to. The only thing I could think is that my exhaust gasket is fried???

 

[racerone]

The water that comes out the tell tale does NOT go through the engine block.------Could be a blockage in the engine.-----Possible blown head gasket.----Start with a compression test.

 

[F_R]

Water is SUPPOSED to come out the exhaust (prop hub). A lot of water, in fact. Can we assume you are running on muffs? Sounds to me like you are starving it for water supply.

 

[Rodrider]

The water that comes out the tell tale does NOT go through the engine block.------Could be a blockage in the engine.-----Possible blown head gasket.----Start with a compression test.

Did the compression check
Came out at 120 psi each

 

[Rodrider]

Water is SUPPOSED to come out the exhaust (prop hub). A lot of water, in fact. Can we assume you are running on muffs? Sounds to me like you are starving it for water supply.

I was on the lake and And was starting to get excessive steam coming off the motor and then the alarm went off turned off the motor let it sit for a while started back up no alarm few minutes later the steam and then the alarm again and repeat till I got back to dock

 

[Rodrider]

Water is SUPPOSED to come out the exhaust (prop hub). A lot of water, in fact. Can we assume you are running on muffs? Sounds to me like you are starving it for water supply.

Excessive steam

 

[racerone]

Your motor is overheating.-----Stop running it and find out why.-----Thermostat checked ?------How did this motor run for you last year ?---Last month ?-----Any other history?----Checked grommet at the top of the water tube ?

 

[Rodrider]

Your motor is overheating.-----Stop running it and find out why.-----Thermostat checked ?------How did this motor run for you last year ?---Last month ?-----Any other history?----Checked grommet at the top of the water tube ?

It’s been running great for the past year, month. As soon as it started overheating we beelined straight back to the dock We take it out regularly from crabbing to fishing and yes I run fresh water through it every time within 2 hrs
I haven’t had to do any work to this motor since I got it 2 yrs ago minis your regular maintenance plugs, prop oil and greeting
Looking at the clymer manual now to start checking those other things
Thank you

 

[webbd]

Have you changed the water pump impeller recently? The impeller is a rubber part that wears as you run the engine and also over time. It might still pump water, but not enough.

Have you ever run the engine without water, even for a few seconds? This is a sure fire way to destroy the impeller.

Chunks of impeller rubber can get stuck in water passages.

As R asked, is the thermostat working?

- DW

 

[racerone]

It was overheating and you kept running it ??-----For how many seconds after the alarm and was it at full throttle ?

 

[Rodrider]

It was overheating and you kept running it ??-----For how many seconds after the alarm and was it at full throttle ?

Never ran it full throttle started trolling from the dock
When the alarm sounds I turn the boat off for a few mins then turn ignition on, when no alarm start it and made my way back to dock
Pulled the t stat and it’s stuck open
Could that be the problem?

 

[racerone]

Not the problem.

 

[Rodrider]

Well I guess I have some troubleshooting to do
Thank you for your help

 

[Rodrider]

T stat is stuck open
Going to run water through it

Have you changed the water pump impeller recently? The impeller is a rubber part that wears as you run the engine and also over time. It might still pump water, but not enough.

Have you ever run the engine without water, even for a few seconds? This is a sure fire way to destroy the impeller.

Chunks of impeller rubber can get stuck in water passages.

As R asked, is the thermostat working?

- D

 

[GA_Boater]

Saying this gently - CHANGE THE DANGED IMPELLER!

 

[Rodrider]

Saying this gently - CHANGE THE DANGED IMPELLER!

I deserve that

 

[kbait]

I had a 15 that would overheat even after impeller change and water peeing from indicator. Thermostat was stuck open. Changed thermostat and it then cooled normally (barrel testing with water level above waterpump). I have no idea why it would overheat w/open thermo, but you could change thermo and test. Probably change out impeller too. Don’t test with water muffs..not a conclusive test for waterpump function.
Good luck!

 

[Rodrider]

Thank you all for your input
Will be replacing the t stat and the impeller and see where that lands me
Again
Thank you

 

[Rodrider]

Update:
Pulled the lower gearbox and inspected
Impeller was in great shape not brittle at all
Pulled the exhaust housing apart, no debris
Blew air where the water would go, all clear
The only problem I found was the t stat was not working after putting it in a pot of of hot water

 

[Rodrider]

I had a 15 that would overheat even after impeller change and water peeing from indicator. Thermostat was stuck open. Changed thermostat and it then cooled normally (barrel testing with water level above waterpump). I have no idea why it would overheat w/open thermo, but you could change thermo and test. Probably change out impeller too. Don’t test with water muffs..not a conclusive test for waterpump function.
Good luck!

Thank you
This is my next step