intermittent water flow from pee-tube

[The Force power]

On this 1991 / 90 hp I just changed out the lower-unit (from chrysler to the Mercury modified version.

The Tell-tail will pee water full stream in idle or medium to low stream in WOT. and just steam
I had the overheat buzzer come on twice in two separate occasions/days

My first thought -the thermostat, but I have (at times) a full stream with a cold engine
My second thought - the impeller. but it is new but maybe spinning on the inner-bushing ??
My third thought - the thermostat faulty closed then open then close when engine hot ??

I have not pulled the LU or the thermostat as of yet. its up at camp & limited amount of tools with me.

Anybody any thoughts??

 

[foodfisher]

Tell tale only tells you if water is pumping. Your symptoms lead me to the impeller.

 

[foodfisher]

Edit, the telltale is usually attached before the thermostat so that makes the impeller even more suspect. Maybe the tube from pump to engine is not seated properly.

 

[jerryjerry05]

Pump/impeller..
Is there a thermostat?

I have a question, You said:

just changed out the lower-unit (from chrysler to the Mercury modified version.
What's that about?
I didn't know they'd made any kind of Mercury adapted drives?
Pictures?????​

 

[The Force power]

Edit, the telltale is usually attached before the thermostat so that makes the impeller even more suspect. Maybe the tube from pump to engine is not seated properly.

Thank you foodfisher,

I wanted to hear this, so i'm not pulling the LU for no reason (getting kind of heavy)

 

[The Force power]

Pump/impeller..
Is there a thermostat?

I have a question, You said:

just changed out the lower-unit (from chrysler to the Mercury modified version.
What's that about?
I didn't know they'd made any kind of Mercury adapted drives?
Pictures?????​

Hi Jerry,

I know....I totally worded that wrong. what I meant by that was; the LU's with the "merc.-style bearing-carrier.

and yes, there's a thermostat

 

[jerryjerry05]

Change the impeller, what condition's the wear plate?
Test the thermo?

 

[The Force power]

Thanks guys for the reassurance of my suspected culprit , I'll bring the necessary tools with me and drop the LU
and test the thermostat (although a little hesitant removing the bolts)

 

[The Force power]

Outcome was.....the tube not insert in the top of pump & cracked the pump-housing.
Inspected the impeller & cup was good, replaced the top-half and bolted back up.
She's pumping like it should, had brought the temp-gun; she's not overheating

I guess I was in a hurry to make that rookie mistake

 

[jerryjerry05]

Hurry, Hurry,Hurry!!!

 

[foodfisher]

Don't forget the drain plug.

 

[The Force power]

Don't forget the drain plug.

:facepalm: yes, but only once noticed it because the pump kicked in while it was still on the trailer