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1959 Johnson Super Seahorse WaterPump Impeller HELP!

K

KaVon

New member
I just replaced the impeller and I'm not getting any water out of the exhaust stern hole. As far as I can tell, all the connections were made correctly, there doesn't seem to me any obstructions (we blew air through when we had the lower unit off and pulled the thermostat off as well). Is there supposed to be a gasket for the water pump housing? The schematic only shows a stainless plate and the aluminum water pump housing itself. Is that machine fit or should there be a liquid gasket of some sort? The two tubes appeared to be fitted well when we put the lower unit up and connected back up. It flowed for about a minute, but then it stopped and the head got hot. Any suggestions? There was no water when we checked the spark plugs.
 
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Yep, twice,, used the new one that came with the kit, and then went back and tried it again using the old one. It did shove some water out, but then it stopped after one minute.
 
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Did you put all the thernostat parts back in?
Did you clean the surface under the stainless plate and use some gasket sealer there?
You are spinning your wheels if it isn't deep enough int the water (you say it is), or bucket is too small (too many air bubbles in water)
 
No, left the thermostat out so the flow had to go out the exhaust automatically. DId that to make sure that it wasn't a stuck thermo.
Cleaned the stainless plate, but no gasket sealer. Do you apply it all over the bottom of that plate? How about the bottom of the water pump housing?
We're using a 50 gal plastic water barrel. It goes as high as the water line would when the boat would be in the water. Used it before on other projects without problems.
 
Use the following sealer between the impeller housing and the impeller plate, and also the plate and lower unit (wherever it touches the lower unit).... Bombardier 3M Product #847 and may be listed as Scotchgrip 847, part number 776964.

Make sure the drive key/pin is locked in the impeller properly.

Install the thermostat and its related components in that engine. Without it, there is no back pressure effect which is required to have the powerhead fill with water. Also see the following:
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(Thermostat Purpose)
(J. Reeves)

Many engines are considered high performance engines and demand a thermostat(s), and many smaller hp engines also require a thermostat for the following reason. The pistons actually distort/twist off round when running. The thermostat is required to keep the outer wall surrounding the steel cylinder, and the cylinder wall itself at a temperature to compensate for the distortion.

With the thermostat removed, the difference in temperature between the inside the cylinder and the water jacket quickly reaches a point whereas (in effect) you have a oblong piston running up and down a round cylinder, or vice versa. Bottom line is without the thermostat, the piston and cylinder wall could be damaged in a short period of time.

The thermostat in your car isn't there simply to have the heater function properly..... think about it.
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You know where the water pump is located... make sure the water level is 2" or 3" above the top surface of the pump.
 
All the 59 Superseahorse 35 HP models left the factory with a thermostat.----And it MUST be installed for proper cooling !!
 
Sorry my bad for some reason I was thinking a 5.5 hp motor. So disregard what I said about the thermostat but where did you get the impeller from.
 
The parts book shows a thermostat for 1959 model 5.5 HP motors.----And what manual do you have ?-----Thermostats were never offered as an " option " on OMC motors !!
 
Wanna bet I had the original owners manual from my Grandpas 59 5.5 hp. It was stated in there a thermostat could be used. Not to mention I am the person who eventually put it in. I forgot how it was worded exactly but it was something to the effect that for colder temps a thermostat could be used. So I think we can agree to agree that I am right about the 5.5 motors.
 
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Joereeves: The impeller I bought was original OMC part in the box. Good to know about the thermo, but we never did let it run more than a minute or two before shut off. Never let it get warmer that we could touch bare handed. I know the key has been in properly and that there is enough water in the barrel to be well above the pump. Will get the gasket material and try that out this weekend. The original manual didn't mention that at all, but from some of the research I've been doing this week, I've found some threads that mention later updates about adding that to manuals after '59. Thanks for the info.
 
KaVon said:
Will get the gasket material and try that out this weekend. The original manual didn't mention that at all, but from some of the research I've been doing this week, I've found some threads that mention later updates about adding that to manuals after '59.
Click to expand...

Yeah, there's a few things that all of us learned over the years that you won't find in any manual.
 
So what do you have anyway, 5.5 or 35hp? A Super Sea Horse is a 35hp. It will operate without a thermostat, albeit too cool. BUT the plastic thermostat housing and check valve MUST be in there or exhaust gasses will go down the second water tube and kill the pump prime.
 
fdrgator said:
so what do you have anyway, 5.5 or 35hp? A super sea horse is a 35hp. It will operate without a thermostat, albeit too cool. But the plastic thermostat housing and check valve must be in there or exhaust gasses will go down the second water tube and kill the pump prime.
Click to expand...
it is a 35 hp that was my fault as I misread the original post.
 
Yep, it's the 35hp. Didn't realize the prime would be cut off. The plastic part was busted, but had a parts motor as well, and that one had a great housing and thermo with a nice check valve as well. Will put it all back together. With the gasket material in place, I'm hoping that will do the trick. Thanks to all for the feedback.
 
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Tried it out.... still no water. The gasket sealer looked like it was going to do the trick, but no go. Still the same problem. Was spitting a little, but no pumping of water. There doesn't seem to be ANY clogs in the system,,, air flows freely when blowing through. Can't lift the tub any higher (the neck of the turning system won't allow the barrel to be lifted more). The thermo cup is back in, along with the thermostat. I really can't see up to the connection where the two copper tubes connect up inside the lower unit housing. Those are rubber gaskets, but they don't show on the schematics to order and replace???? Could I be not aligning perfectly there and causing a small leakage??? Pretty much flummoxed at this point.
 
Just what do you mean by spitting a little? Do you know that they only spit out a spray till the thermostat opens? Do yu know that the 'stat is constantly sampling teh water temp and opens and closes as necessary to maintain proper temp? Do you know that it idle it may never get warm enough to open? Not to mislead you into thinking it is ok when not, just sayin'. I suggest you launch the boat and start it up to verify you really do have a problem

The upper ends of the water tubes go into rubber grommets just like the lower ends. If they are snug and secure, they probably are ok.
 
Yeah,, ,it got hot,,, turned it off when the head was hot to the touch. Well over 170 let alone 143, so it should have popped. The thermo is on the way. Ordered a new one and a new gasket. The spring up there was great as was the plug and black bowl. The 'spitting' might just be hot water with the exhaust splashing getting up those tubes. So I should get new grommets like the lower end for the top too?
 
The 2 tubes were put into the proper place in the exhaust housing first I hope.----Then it is easy to guide those tubes into the pump grommets.----Water has to be 6" above the pump when testing in a bucket.----No way to get around that fact.
 
The 1959 35hp Super Seahorse Johnson, as I remember it, and double checking with the book, has a pressure relief valve, a water bypass valve so to speak. As such, especially with a new water pump assembly... water should be shooting out that large exhaust relief hole halfway down that long exhaust housing like it was blasting out from a large garden hose whether the thermostat is open or not.

And KaVon... you state that it is just spitting? That sounds to me like either one (or both) copper water tubes missed the greased grommets (you did lubricate them slightly didn't you?) and possible hit the edge of the grommet which would fold them over effectively creating a flexible shut-off valve... OR... you are misjudging where the water level belongs in that tank, trash can, large barrel, whatever.

Knowing where that water pump is situated, the water level should be approximately 7" or higher above where the lower unit joins to the long exhaust housing to be completely submerged. That water pump is not a self priming pump and must be submerged in order to function properly. Anything less and the pump will draw air.
 
The 1959 35hp Super Seahorse Johnson, as I remember it, and double checking with the book, has a pressure relief valve, a water bypass valve so to speak. As such, especially with a new water pump assembly... water should be shooting out that large exhaust relief hole halfway down that long exhaust housing like it was blasting out from a large garden hose whether the thermostat is open or not.​

Sorry, I gotta disagree. When the 'stat is closed, water goes through the relief valve and back to the water pump's inlet side via the second water tube, for recirculation till it gets warm enough. Just goes 'round and 'round, so to speak. A little bit goes out the exhaust during that phase to cool the exhaust. Nowhere near a garden hose flow.
 
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