Mariner 20hp Waterpump DRIVING ME CRAZY

HI, newbe here. I just replaced the waterpump in my 1995 Mariner 20hp outboard. I water tested it on the driveway, and all is great. Water pee's out just fine.

I just took it on the lake and at higher throttle the entire upper half of my engine compartment is filling up with water.....

WTF????

Mike

Re: Mariner 20hp Waterpump DRIVING ME CRAZY

Are you sure you got the water tube mated with the bottom of the powerhead?

Re: Mariner 20hp Waterpump DRIVING ME CRAZY

coastalrichard said:

Are you sure you got the water tube mated with the bottom of the powerhead?

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There is not a lot of room to navigate under there. I was sure, but suspected this might be the concern....I guess if this was not mated a **** load of overflow would happen.....and fill up my upper engine compartment....??

Re: Mariner 20hp Waterpump DRIVING ME CRAZY

I don't know if that model has a t-stat. If not, it likely pees while still not getting all the water to the top.

Re: Mariner 20hp Waterpump DRIVING ME CRAZY

mgreig0230 said:

There is not a lot of room to navigate under there. I was sure, but suspected this might be the concern....I guess if this was not mated a **** load of overflow would happen.....and fill up my upper engine compartment....??

Click to expand...

Let's look at facts as I see them from here.

Prior to your water pump removal you had no water in the upper compartment.

You did the replacement and now you have water......where is the water coming from...that wasn't there before? What did you change? Get the drift.

The only confusing thing is that you said that you had your tell tale working which is nothing more than an small hole bored in the engine block/a water jacket that is part of the engine block cooling, and a tube to route the water from this hole outside where you can see it.

Just back the truck up and look at what you did. If the water pump is pumping water and maybe you didn't get the tube stabbed properly or lost a gasket........

HTH,
Mark

Re: Mariner 20hp Waterpump DRIVING ME CRAZY

Is there a gasket up inside there? I really think that I am not stabbing the return into the seal up top.....will continue.

Thanks very much.....will post with my sucess...

Texasmark said:

Let's look at facts as I see them from here.

Prior to your water pump removal you had no water in the upper compartment.

You did the replacement and now you have water......where is the water coming from...that wasn't there before? What did you change? Get the drift.

The only confusing thing is that you said that you had your tell tale working which is nothing more than an small hole bored in the engine block/a water jacket that is part of the engine block cooling, and a tube to route the water from this hole outside where you can see it.

Just back the truck up and look at what you did. If the water pump is pumping water and maybe you didn't get the tube stabbed properly or lost a gasket........

HTH,
Mark

Click to expand...

Re: Mariner 20hp Waterpump DRIVING ME CRAZY

I figured it out.....I was installing the return tube correctly inside, it turns out that I guess with the new pressure from a new water pump, I blew out the gaskets on the cylinder head manifild (side mounted-easy to remove).....Thank you very much.....this really stumped me, as I did not expect something else to fail....

mg.