Water issue

[wild n crazy]

Hello once again, I have a water problem but I don't know where to start. I noticed that the water usually coming out of the two thumb size hole in the mid part of the motor but last time I took my boat out, the buzzer buzzed, I realized I have water problem, my tell tail does squirted water, but I noticed that the 2 thumb size hole in the mid rear of engine, the water don't come out from there, I like to know where is that water discharge from? do I have thermostat problem, how can I tell? please help. thank you in advance

 

[Bosunsmate]

Re: Water issue

Whats your motor?
yes probably a thermostat problem

 

[F_R]

Re: Water issue

The water coming out the rear has gone through the powerhead and done its job. The tell tale is water that has not yet gone all the way through the powerhead. First things first, check the water pump. It may be pumping, but not pumping enough.

 

[wild n crazy]

Re: Water issue

100 HP Johnson 1979 that's my motor sir

 

[wild n crazy]

Re: Water issue

and thank you Mr F-R. since the thermostat is easier, I take a look at that first, then my next assignment is the water pump, since the suggested that I need to change the impeller old or no. and thank you for your explaining of the water flow.

 

[Bosunsmate]

Re: Water issue

Have you felt if both heads get hot or just one?
Were you at idle or running past middle throttle when it overheated?
you could try running it without the thermoststs and see if that stops the overheat. if it does be sure to replace them as otherwise you will get a very hard to warm up motor and you will risk a cold seize.
If you take off the thermostat cover, its a bit of a pain, ive drilled holes into the lower cowling to do this and replugged them with a rubber boot, there is a little hole in the middle valve body, if that gets blocked the whole motor will overheat.
As FR says it might be the water pump, is it pissing out strongly out the tell tale? It should fill the block within about three seconds and **** strong on these after start up.

 

[Bosunsmate]

Re: Water issue

I recently rebuilt one of these that had a worn impeller and it overheated, blowing three sets of rings and a hole in the number 3 piston. They had thought waiting about 13 seconds for the motor to start pissing after start up was normal, but it meant a very worn impeller.

I drilled the hole in that thermostat valve body a touch larger so that itd take something bigger to block the water flowr

 

[wild n crazy]

Re: Water issue

I can't really tell when it's started to overheat, it was idling fine, then I put it gear, that's when it buzzed, when you talk about the head gets hot, I mean how hot it's hot to you, I felt it, and it's hot, and I didn't bother to touch the other side, the tell tale does **** almost right away, the only thing I see different is the water didn't exit the 2 thumb hole in the back of the engine, I know the thermostat when it reach it's temperature, it'll open up to let the water through, after that, can you tell me where that water go, because I was about to take the thermo. housing apart, I see it's kind a hard, and like you say, it does not have room to turn the bolts. and I also noticed that around the housing, it 's no where near the 2 thumb holes in the back. so I've stop and come in to read your replie. I am very glad and very thanks to have people like you up here helping other.

 

[Bosunsmate]

Re: Water issue

Yep those thermostats are hard to get out. You will need to remove the water pipes to them too. I just drill through the cowling so i can get a socket in their correctly, then i put a grommet in both holes afterwards
The water circuitry in these motors is still a mystery to me. There a holes everywhere that all do certain things. Even little pin holes ones halfway up the heads in between the cylinders i just saw the other day do something.
What you a describing is a thermostat problem so just go for it. You will probably need to replace the two gaskets that go either side of the thermostats. They a not expensive. About $1. OMC part number is 0332369 sierra which is a 2 pack is 18-0977-9.
If no water is coming out those ports id suspect that hole might be blocked as itd be unusual for both to go at once.
You could run it without the thermostats to see if that was the problem but dont do that for long as running cold on motors causes problems.

If you have muffs at home run it on the hose and see how long it takes too overheat as a baseline. Feel each head for any temperature difference. Post a video of the water pumping from start up if you have any concerns about if its pissing ok

 

[wild n crazy]

Re: Water issue

It's sux nowaday, by the time I get home from work, it's very dark for me to do any thing, the weekend I was free, but raining, I'll reply when I get my impeller changed, and my thermostat, transmission oil, and also have to fix my trim, hyd. leak too much work, LOL it's getting to my wallet

 

[wild n crazy]

Re: Water issue

I do have the video, but I don't know how to attatch video, but this is what my impeller and housing looks like, so I went and changed both out, now my engine is not buzz no more, but thanks to you and other that are good hearted of helping other trying to save a little bit of money .

 

[Bosunsmate]

Re: Water issue

No worries. Yeah that impellers worn.
Never start the motor until its submerged and Turn the motor over with the muffs on or in a tank every few weeks in winter, or whenever your off season may be. Thatl keep it going for longer

 

[boobie]

Re: Water issue

Bosun, how are you going to do this when the temp is minus 20* and the lakes have 2 feet of ice on them??

 

[Bosunsmate]

Re: Water issue

Bosun, how are you going to do this when the temp is minus 20* and the lakes have 2 feet of ice on them??

I thought it was powering an icebreaker!

 

[wild n crazy]

Re: Water issue

I thought it was powering an icebreaker!

To all that have a hard time taken out the thermostat on the 1979 Evinrude 100 HP. there are a few bolts you need to take out to move the lower motor cover, that will enable you to put a box end wrench on to the two lower bolts on the thermostat housing from the bottom side. that's how I got mine off. my thermostat is stuck even when I cook it, it don't even move.

 

[racerone]

Re: Water issue

The impeller picture in post #11 tells me the pump was run dry.--------Quickest way to ruin one !

 

[boobie]

Re: Water issue

Or just plain worn out from years of use.

 

[btomlins]

Re: Water issue

Yeah check that little hole between the t-stats. I found mine plugged yesterday with some scale in it.
I wonder if there is a "new" model that doesn't plug as easily?

 

[tazrig]

Re: Water issue

You should replace your impeller every other year just as preventative maintenance regardless of how many hours you have on the engine.

 

[wild n crazy]

Re: Water issue

Yes, it was worn out , I bought the boat used. so I don't know how long when the last impeller changed. I bought new T-stats and kit. Now I am back in here looking for diagram to put it back in, to be sure, cause I don't like re-do LOL