1955 15 hp Evinrude Cooling Problem

[rfevans]

Ok guys I am not much of a poster and I try to read till my eyes bleed before asking but I am stumped. I bought a 15 hp 55 Evinrude Fast twin with two line tank and hose at a auction last friday for 42 bucks and as the old story goes it was suppose to run.Well when I got it home i realized just what I had got myself into...lol the tank had four inches of rust in it and was not usable at all you can stick a screw driver through the bottom. So I started researching here and the progress Ive made I am pretty proud of in one weeks time most of witch was waiting on parts. I have rebuilt the carb and converted to a briggs and stratton pulse pump and a new wear plate and water pump. I put it in a run tank but I cant get it too cool when I pulled the lower unit the first time I noticed that who ever had installed a new pump before me had kinked up the grommet on the pump side of things the grommet itself had the copper tube plugged and there was no way it would cool. I replaced the grommet when I put back together but still no cooling. My fear is that when the P.O. installed this he cut the grommet and a piece got sucked or pressured up in the power head and created a blockage. The other thing I thought it might be is thermostat stuck but I am not sure this engine has one. I don't have a parts break down of this engine. The good thing about all this is I have it purring like a kitten but just cant get it too cool. I am a novice with outboards but pretty handy with a wrench on most things this was my first outboard carb rebuild and water pump so I could have missed something. If anyone has any ideas let me know I am going to pull the lower unit again tomorrow and see if I can figure this out...Thanks in advance signed almost fishin..

 

[HighTrim]

Re: 1955 15 hp Evinrude Cooling Problem

You're getting there!

There is no t stat, so nothing to worry about there.

First ensure the water intake area is free of debris. Second ensure you put the impeller key into the drive shaft. If the gearcase is down, run compressed air or the garden hose up the water line to see if it exits at the exhaust. Is it pumping at all? Is the water level just beneath the exhaust? The pump needs to be completely submerged beneath the water line, it is not self priming.

 

[Daviet]

Re: 1955 15 hp Evinrude Cooling Problem

A couple of thoughts.
I did not see a thermostat in the parts breakdown.
How deep did you have the engine submerged in the barrel, water needs to be just below the exhaust port.
You can remove the lower unit and submerge it in water and spin the driveshaft with a drill and see if it pumps water.
With the lower unit off you can try blowing into the water tube with compressed air and see if it sounds like it is going through.

 

[rfevans]

Re: 1955 15 hp Evinrude Cooling Problem

Thanks guys for the quick reply's...I had it submerged with in a inch or two of the exhaust port. so I know that cant be it...I will check the intake tomorrow and then drop the lower unit.It will probably be something stupid like the key but I am pretty confident in the install...I'll try the compressed air and check for blockage that way....I had a bad feeling about that grommet on the pump on the install as cut up as it was by the copper tube...Hey at least the fuel pump conversion worked witch I was skeptical about...almost fishing....

 

[rfevans]

Re: 1955 15 hp Evinrude Cooling Problem

Ok got it figured partly out...I pulled the lower unit and sure enough compressed air would not pass through the power head.....I took the water tube out of the upper grommet and took some mechanics wire with a tiny hook bent on the end and ran it up in there. Found the blockage not far in there turned the hook and pulled out piece the size of a bean. I then used compressed air and could hear the air passing through I also used a water hose after the compressed air and flushed got a few more very tiny pieces out. I then bolted the lower unit up and presto it started cooling got good flow out of the exhaust port so Im calling that good. The only problem I am having now is keeping it running...I had it running good before and it still idols well but runs out of fuel if you run it open throttle for a while. I am kinda starting to wonder if my fuel pump is working. I noticed it works fine with the tank in a elevated position but down in the boat its not.The other thing is now the primer bulb will not pump up hard so something is bypassing or a vacuum leak. I tested the carb before the install and it was fine. I guess that I will start at the tank and work my way through one piece at a time...Any thoughts or suggestions would be great...thanks again...still almost fishin..

 

[Daviet]

Re: 1955 15 hp Evinrude Cooling Problem

Did someone convert it to a single hose system?
If you have to keep pumping the primer bulb to keep it running it is a sign that the fuel pump is on it's way out.

 

[rfevans]

Re: 1955 15 hp Evinrude Cooling Problem

Yes in the earlier post explains..I put a fuel pump on it....I used the vacuum plug plan took the intake cover off took out the one way valves and used a vacuum plug to plug one of the two holes cut it to fit to so that the intake would hold it in place with pressure and bolted it back up...is there a way to check that running to see if its doing what its suppose to be for the pump???

 

[Daviet]

Re: 1955 15 hp Evinrude Cooling Problem

You can pull the fuel line going to the carb, pull the engine over, check the pressure and flow coming out of the line to the carb.
You could also install some clear fuel line between the pump and carb, take it out and run it and watch the fuel flow.

 

[rfevans]

Re: 1955 15 hp Evinrude Cooling Problem

I'll try that I have some clear fuel line...I elevated the tank to wear its gravity feed and it runs better but if I dont squeeze the bulb it will still run on of fuel...I was trying to figure out how to check the pulse from between the power head and the pump it self just to see it that was working...It is a new pump but that does not mean anything I know...Im thinking a small balloon on the vacuum line might work just to see if its pulsing...