Old Johnson Seahorse 5.5hp

[mhieronimus]

Hi everyone,

New to the forum here, and have been looking around for an answer to my question but can't seem to find it. I just picked up an old Johnson Seahorse 5.5hp from my grandparents. It was tuned up and run last year by a professional according to them.

The motor has the pressurized tank, which I have primed, but for the life of me I can't figure out how to start it. I've got the choke up but it has high speed and low speed adjustments and I'm not sure where to set those at. According to the starting instructions on it, it says to put them in the 'starting' position.. but beats me exactly what the starting position is. The tank still holds pressure well, I'm getting spark, so I'm thinking of maybe cleaning the carb tomorrow.

If anyone's got any advice for me, it would be appreciated, this is a great looking little motor, clean as a whistle and would LOVE to see it up and running great again. If ya'll need to know the year I can look it up. Thanks

Matt

 

[samo_ott]

Re: Old Johnson Seahorse 5.5hp

What model# is it?
The gas cap must be tight on the pressurized systems for the fuel to pump.
How did you check spark? Use a proper spark tester. Usually the coils fail due to age so it is important to test properly.
Read the top secret thread at the top of the forum. Read awakening a sleeping outboard.
Initial position are 1.5 turns out from stop position on the upper, slow adjust needle, 3/4ers turn out on the lower, high speed adjust.

 

[mhieronimus]

Re: Old Johnson Seahorse 5.5hp

Actually I got it running, but after a minute or two it will cut out. Try and restart it and nothing. I've got to prime the line again, the tank itself seems to be holding pressure but it stops getting fuel. I'm looking right now into getting a conversion so I can go with a siphon style tank instead. Thinking that should fix that problem...

But then there's another problem... when I go to turn the throttle to shift or slow, it dies. Doesn't slow down sputter and die, it just straight up dies like I went right to "Stop" position. Anyone have any idea on that one?

 

[F_R]

Re: Old Johnson Seahorse 5.5hp

First mistake you made was reading the instructions. (LOL). If it was tuned up by a pro last year, theknobs were set and there was no need to go twirling them. If you did, put them back where they were. Prime it, choke it, set the throttle on start, and pull it. Push the choke in when it starts.

Next you need to understand that pressure tank. You fill the carburetor with gas when you work the primer button on the tank. Once it is running, the motor pumps air into the tank, which forces the gas out to the motor so it can continue to run. However, it may be necessary to pump the primer a few more times to keep it running till the pressure builds up enough to keep going on it's own. As somebody said, the cap must be tight.

You can pretty much ignore the lettering on the throttle grip. They are not accurate, only a generalization. Fast is that-a-way, slow is the other way, etc.

Why does it conk out when you try to slow it down? We don't know. Does it involve the knobs?? Lack of tank pressure?? Something actually wrong with the motor??? Hard to tell from a distance.

BTW, there is no need to replace that tank if it is in operating condition, and clean inside, with fresh clean gas.

 

[mhieronimus]

Re: Old Johnson Seahorse 5.5hp

First mistake you made was reading the instructions. (LOL). If it was tuned up by a pro last year, theknobs were set and there was no need to go twirling them. If you did, put them back where they were. Prime it, choke it, set the throttle on start, and pull it. Push the choke in when it starts.

Next you need to understand that pressure tank. You fill the carburetor with gas when you work the primer button on the tank. Once it is running, the motor pumps air into the tank, which forces the gas out to the motor so it can continue to run. However, it may be necessary to pump the primer a few more times to keep it running till the pressure builds up enough to keep going on it's own. As somebody said, the cap must be tight.

You can pretty much ignore the lettering on the throttle grip. They are not accurate, only a generalization. Fast is that-a-way, slow is the other way, etc.

Why does it conk out when you try to slow it down? We don't know. Does it involve the knobs?? Lack of tank pressure?? Something actually wrong with the motor??? Hard to tell from a distance.

BTW, there is no need to replace that tank if it is in operating condition, and clean inside, with fresh clean gas.

Like I said, got it running, and I did try keeping it running by hitting the primer a couple times, can do that non-stop but when I stop after a minute or so it'll conk out. At the moment the only two throttle settings it has are "start" and "fast". It'll go just fine when in the fast position. I was looking at replacing the tank because I'm sure it'll end up having problems eventually... that and well pressurized gas fumes... not the greatest thing to have around.

Figured I'd just bring up the shift/slow throttle issue see if someone else was having a similar issue and what their fix was.