Evinrude 15, 1980 water circulation

[Mikko]

By the way, those two motors look pretty identical. Both look like 1980 models. Neither look like a 1982. At least the covers look like 1980 motors, but also the mid-sections. Do they have different model numbers?

They do have different model numbers (1980 and 1982, year letters CS and CN).

 

[Mikko]

to lift powerhead you need to loosen 9 bolts + 1 bolt from gear tension selector.
you dont have to play with trotle handle when takeing out powerhead.
if you lift powerhead everything will vertical go up
when putting back its be careful with this vertical trotle shaft.it should fit in squere noth

This was what I was wondering. I could not figure out that the vertical throttle shaft comes up (out of control gears) without opening anything (cotter pin or two bolts up there).

 

[OptsyEagle]

I removed the throttle linkage, more for the benefit of when I drop the powerhead back down, then for removing it. There is a lot going on when dropping the motor down, I thought avoiding the alignment of the vertical shaft would be useful. Both hands will be busy holding up the powerhead, which is quite heavy and needs to be held high to get the exhaust and water tube into the correct places.

But as mentioned above, it is not absolutely necessary.

 

[Mikko]

No Title

I am progressing However, grommets were in pretty good shape. I'd like to remove and check the plastic Ell, but I'm afraid of breaking it while opening as it seems to be tight. At this stage, maybe I should open the water jacket as well? I'm gonna open the thermostat cover anyway, but I think not to open the head gasket as it has not overheated.

 

[OptsyEagle]

If you are having water pumping issues, I would definitely check the thermostat and water jacket while you have the powerhead off. No need at this stage to remove the cylinder head. Did you remove the exhaust tube to look at the grommet? Also, I do not know what a "plastic Ell" is.

 

[jrs_diesel]

The plastic ell is the connector screwed into the engine block for the tell tale hose.

Pull the water plate off to check out the thermostat and spring, and also to get a look at the general condition of the water jacket. If there's a bunch of crud there, then it would be wise to pull the cylinder head and clean out all of the water passages.

 

[Mikko]

What about the side exhaust water cover where the ell is connected? I blew air to the water tube with thermostat cover open and felt good blow from the thermostat housing but not from pee hole.

 

[jrs_diesel]

If your just blowing air up the main water tube from the pump, them almost all of it will go to the thermostat housing (path of least resistance).

Shoot some air through the water indicator outlet and see it that is clogged.

If it is clogged, it is usually the plastic ell since it's a 90? turn.. If you still have the powerhead off the midsection, just unscrew the ell from the exhaust plate and check it. Just be careful doing that since it is plastic and could break. If it does break, they are relatively cheap to replace.

One alternative is to run a piece of weed eater string through it first and hopefully unclog it that way.

 

[badboybill88]

I had an water circulation issue that sounds somewhat similar to what you're describing, and although I don't believe it to be the exact same, I came across a webpage that I found very helpful;
http://www.leeroysramblings.com/water_circulation.htm

Hope it helps!

 

[oldboat1]

need to remove the inner exhaust tube, reattach with new powerhead gasket in place.

 

[raczekp1]

drop exhoust tube to see upper grommet.
also install new termostat while the powerhead is out

 

[Mikko]

I removed the exhaust tube when I dropped the mid-section. Grommets were not so bad but I am gonna change the inlet one. It seems that there is no clear evidence about the problems in water circulation. It could be that water was circulating properly but pee hole (ell) is clogged.

 

[Mikko]

As expected the nozzle of the plastic ell was broken when I tried to open it (it was really tight), but finally I was able screw it out. It was almost totally clogged due to some debris (most likely from worn impeller vanes). So, lot of work almost for nothing, but still I think I could not have realized this without pulling the powerhead. Now I am pretty sure that cooling was working properly and I don't have to open the head. Thanks to all of you who provided me useful information. Let's see how I manage to put all together again.

 

[Mikko]

No Title

Necessary parts have been bought, but before the rebuild I'd like to ask the opinions from the others concerning the use of any sealant/glue on these gaskets. I have read the opinions here in the forum and some people seem to be in favor of using sealant while the others not. I am not going to use any sealant glue on these two gaskets especially as the both aluminium surfaces are in very good condition. Still I think there is some kind of glue in the original OMC gaskets?

 

[juno pierrat]

while things are apart take a look at this old post http://forums.iboats.com/forum/engin...ng-a-tell-tale
well after reading leeroys page, its all covered there

 

[oldboat1]

Install the t.stat before you bolt up the powerhead to the leg. The cover is a tight squeeze (need to remove the cylinder head to get at it, if the powerhead is on the motor). Problem is location of the t.stat down low at the pan (proximity to the hood latch). On leeroys page, he tells you how to reconfigure the latch bolt to give access -- have done that too. It's easier to work with the cyl head off, though, or the whole powerhead like yours. The t.stat cover is poorly designed, IMO, on the earlier models (pre '85). There is one bottom bolt, not two as your gasket would indicate (you have the right gasket). Recommend some OMC gasket sealer or some Permatex (black stuff, not the silicone RV sealant). Prep like you would a head gasket, and torque evenly to specs.

 

[Mikko]

I know the problem with t.stat cover if the powerhead is on the motor since I changed the head and t.stat cover gaskets in one of my motors without pulling the powerhead. Now it is only question about using any sealer in the gaskets or not. I did not use sealer when changing the head gasket and t.stat cover gasket in my previous repair.

 

[OptsyEagle]

I always put a light coating of OMC gasket sealer on those two gaskets but they would probably work fine going on dry as well. Personal choice I suppose.

 

[Mikko]

No Title

I succeeded in putting the parts back in place again, even though I was not very convinced that everything goes right, especially as the motor was upside down for several weeks There is a very strong tell-tale stream now as seen in figure1, so everything appears to be ok (although I see it very strange that the rubber upper grommet of the water tube goes against the base gasket). One thing that still surprises me is the water coming out from somewhere where the shift rod is located (see arrow)? There has been some discussion about it in this forum before? I run the motor about 30 minutes and the max temperature I measured was about 52 degree Celsius (about 125 degrees F, see figure2). Of course it was not possible to use full throttle in this tank, but still I believe it is ok now.

Another question concerns my second Evinrude 15 which I also tested in the tank for several minutes. I wonder why a lot of water is coming out from exhaust relief (see fig3) immediately after the start? This is the motor which experienced an intermittent tell-tale stream while in full throttle and I thought it was overheating a bit. In the tank max temp was only 40 degrees Celsius. In the tank everything seemed to be ok.

 

[OptsyEagle]

I believe that model has the T-stat at the bottom of the cylinder head (as opposed to the top) like my 1976 model. In my model the water out the exhaust relief hole is the only indicator of water flow and it is usually an almost unnoticeable mist until the T-stat opens and then it sprays out like your 3rd picture up there. If you are getting that much right away perhaps it does not have a t-stat in it or it has failed open. Just a thought. In the middle picture I suspect the t-stat is closed because I know from testing that it only starts to open at around 140F and is usually fully open at around 150F. I assume you measured the temperature of your second motor to see what temperature it was getting to.

As for water exiting around the shift rod. I suspect when this motor was brand new that probably did not happen but after 35 years the seal there is probably breached. Since it does not create a problem, I would ignore it.