Rebuilding a Johnson Seahorse FD-10

[Basher]

Re: Rebuilding a Johnson Seahorse FD-10

Hello Everyone,

On the weekend I thought I would replace the gasket on the exhaust cover. Last time I test ran the motor I noticed it was burping some water out of the lower corner near the bottom spark plug. Upon removing the exhaust cover plate I noticed that the gasket was torn in that location.

Now I went down to NAPA and got myself some black gasket material, if it were sheet metal I would say it was about 16 Gauge in thickness. Seems to match fairly well to the original gasket material. I cut out two new gaskets and installed them, after cleaning the housing, metal baffle plate and cover of all excess grunge and old gasket material. While I was doing this I thought I might as well change the intake gaskets as well, cause if they were as brittle as the exhaust gaskets they would need to be changed sooner rather then later anyways. So I removed the covers and gaskets and installed two new ones there as well. I got a nice look at cylinders and rings while in the process of doing this, all appeared to be in extremely good condition, no scratches or rust anywhere!!! Hooray!!!

Now my question is, should I be using any type of gasket sealer on either of these four gaskets, there didn't appear to be any prior to replacement and I did not use any when installing the ones that I made but I was just wondering before I go and give it another test run.

I will post my pics of the inside of the intake and exhaust ports as soon as I can, but I just bought my first house and take possession on Friday, and the downloading cables are packed somewhere.

Basher

 

[Basher]

Re: Rebuilding a Johnson Seahorse FD-10

Hey everyone,

I finally got it out on the lake in Inveremere B.C. It runs great and planes out in about 10'. I got someone to pace me and clocked me at 17 MPH, I LOVE IT

Thanks to everyone here who helped me to get this old girl out on the lake.

Wade

 

[rjezuit]

Re: Rebuilding a Johnson Seahorse FD-10

Just for comparison's sake, how big a boat and how much of a load? Thanks, Rick

 

[Basher]

Re: Rebuilding a Johnson Seahorse FD-10

myself and one passenger in a 12' 6" aluminum, only load was motor and 4 Gal fuel can.

Wade

 

[tmcalavy]

Re: Rebuilding a Johnson Seahorse FD-10

Nice job on the Johnson. Wouldn't take anything for my restored FD-11. Nice skiff, too. Next time out, take an old milk crate and put it just in front of the rear seat. Sit there and see if she planes off quicker and runs faster. You can make a simple tiller extension from some pvc pipe, radiator clamps and a hunk of round wood handle. My FD-11 used to make my 15-foot tinny fly with just me and the dog in the boat. Spent less than $20 on the tiller extension.

 

[wbeaton]

Re: Rebuilding a Johnson Seahorse FD-10

Looks good. I get a max of 32 kmh / 20 mph GPS on 12-14' aluminum boats like yours. I suspect you get the same.

 

[dgmarklin]

Re: Rebuilding a Johnson Seahorse FD-10

Hi Everyone,
I am new here, but was surfing the web with google on my 15HP and ran across this post!

I have a FD-10 15HP too, and I am also in the process of working on her. I have gone through many of the same issues as this guy has. I got her running pretty good yesterday and put a video up on youtube.

http://www.youtube.com/watch?v=pe8rzWtSoIE

That afternoon though I went back out to try her again and she stopped pumping water. You can see in the video that she pumps fine, I don't understand why she would stop so suddenly!

Any Ideas?

Thanks

 

[Sea18Horse]

Re: Rebuilding a Johnson Seahorse FD-10

Did you replace the water pump impeller? If not that would be the first thing to do. Many people get an old motor like this running, see the water pump working fine and say "oh it's ok I'll just run it like this for this season and change it next winter" But what they don't seem to understand is that they all work fine....right up until the moment when they don't any more. If your very lucky that moment will occur when it's in the test barrel and you're looking right at it. But it can just as easily occur while your screaming across the lake at wot!

If you have replaced it I'd say that looking at your video the water level is borderline. The water pump housing itself needs to be submerged in the water. I can't tell for sure but yours may be a bit low. Make sure the water is up to the middle of the leg mounts and try it again.

Cheers................Todd

 

[BSDenning]

Re: Rebuilding a Johnson Seahorse FD-10

You probably need to replace the impeller, just as Basher did.

 

[Sea18Horse]

Re: Rebuilding a Johnson Seahorse FD-10

BTW, nobody needs a hood for one of these do they? I got an FD-12 parts motor. So I've got the hood sitting here on my bench at work and I know it just needs to go in the scrap metal barrel. But I just can't seem to make myself do it.
I'd much rather give it to someone who can use it.

Cheers.................Todd

 

[dgmarklin]

Re: Rebuilding a Johnson Seahorse FD-10

Thanks for the quick reply guys.

I have ordered a new impeller and the plate offline, hopefully it will be here soon. Haha, you guys are right though, thats what I was thinking, lets just run it this season as is. I think I "jinxed it" by saying I was gonna go boating out on the river tomorrow...OH WELL..

I am going to take her apart this afternoon probably to get a look at it in there.

Todd, the water was up to the pump, above it even, I learned about that last time I ran it. Everytime I get her running I learn something new it seems. This motor, like others, is a feisty old thing. I figured out last night that I have to move the low speed mix to the left to get her to start up, and then slowly shift her right.