1957 35 hp Johnson seahorse won't start

[HighTrim]

Re: 1957 35 hp Johnson seahorse won't start

Well pull the head first and have a look at the gasket and the cylinders, post pics if you can.

If it is just a head gasket you are in the clear. Dress the head before installing the new gasket as follows. Also ensure you use the proper torque in the proper sequence. 220 inch/lbs....start at 110 inch/lbs for a rotation, then about 165 inch/lbs, then the full 220 inch/lbs.

 

[Castellina]

Re: 1957 35 hp Johnson seahorse won't start

Thank you I will go take a look and post pics

 

[1946Zephyr]

Re: 1957 35 hp Johnson seahorse won't start

Can you post some pictures of this motor? The cosmetics will tell us a lot about the condition. If you got 73 on each hole with the hand starter, then that is actually pretty good, providing the compression releases are working the way they're supposed to. I usually open the throttle all the way and give it about 5 or 6 revolutions to get the readings. If you use the hand starter, then you can remove the compression release lever, by removing the two screws the connect the long stainless bar that goes to the recoil assembly or just lift the end out of the top of the recoil.

 

[Castellina]

Re: 1957 35 hp Johnson seahorse won't start

I attached some photos of the engine here

 

[HighTrim]

Re: 1957 35 hp Johnson seahorse won't start

Looks like it will need a good decarb later, but hard to see the cylinders from the pics. Any noticable scratches or damage to the cylinder walls?

Next remove the small bypass covers on side of the motor, and try to push on the piston rings with a screwdriver. They should bounce. Do they>? If not, they are stuck with carbon.

I cannot see any damage from the pics to the head gasket, did you notice anything in person?

 

[HighTrim]

Re: 1957 35 hp Johnson seahorse won't start

Looks like it will need a good decarb later, but hard to see the cylinders from the pics. Any noticable scratches or damage to the cylinder walls?

Next remove the small bypass covers on side of the motor, and try to push on the piston rings with a screwdriver. They should bounce. Do they>? If not, they are stuck with carbon.

I cannot see any damage from the pics to the head gasket, did you notice anything in person?

 

[Castellina]

Re: 1957 35 hp Johnson seahorse won't start

No I do not see any damage to anything. I am going to go open the bypass cover and check the rings.

 

[HighTrim]

Re: 1957 35 hp Johnson seahorse won't start

Let us know what you find.

Should also manually clean up alot of that carbon from the piston tops and inside of the head while you have it apart.

 

[1946Zephyr]

Re: 1957 35 hp Johnson seahorse won't start

Well, that certainly is a decent looking motor and should be revived without too much effort. I've seen a lot worse, that ran good. Don't give up on it. I think once you get the bugs out, it'll be a good runner. That in my book is the best motor OMC built and they're pretty forgiving. Like HighTrim says, do a good de-carb on it.

 

[Castellina]

Re: 1957 35 hp Johnson seahorse won't start

The bottom cylinder piston rings do bounce but the top cylinder rings don't.

 

[HighTrim]

Re: 1957 35 hp Johnson seahorse won't start

I was expecting it to be the other way around by the pics.

Well I guess you have a decision to make. Either re ring the pistons now, or gamble that a good decarb will free them up later. I would likely just re ring now and be done with it, but have been proven wrong in the past and others have successfully got the rings un stuck with Seafoam and a good decarb. That is not to say it will work for you though.

After new rings, new head gasket and dressing the head your compression will be up where it is supposed to be, and she should start up with ease.

You could try removing the exhaust cover as well, and spraying seafoam all over the cylinder from all 3 sides and see if you can free them up, but I personally find the Seafoam works best on a running motor. Cant hurt to try though I guess.

 

[Castellina]

Re: 1957 35 hp Johnson seahorse won't start

I will try using sea foam and if that doesn't work I will re ring the pistons. Thanks for all of your help. I appreciate it very much.

 

[Castellina]

Re: 1957 35 hp Johnson seahorse won't start

I used the sea foam and that worked. It freed the rings up. I also ordered a new head gasket.

 

[HighTrim]

Re: 1957 35 hp Johnson seahorse won't start

Awesome. Dress the head before you install the gasket as I posted earlier. It only takes a few minutes but is necessary. Equally as important is the torque and torquing sequence.

Use a putty knife or steel wool or something and clean the pistons as best you can, then when running do a good decarb on her as described in the FAQS.

Keep us informed on how it goes.

 

[Castellina]

Re: 1957 35 hp Johnson seahorse won't start

Thanks for all of your help. One more thing. When I opened up the exhaust cover there were som scratches on the piston. Does that matter?

 

[HighTrim]

Re: 1957 35 hp Johnson seahorse won't start

Light scratches are ok. If they are gouges that you can catch your fingernail on they may cause trouble.

 

[Castellina]

Re: 1957 35 hp Johnson seahorse won't start

Ok I appreciate all of your help. I will put everything back together and see what I find, and post what happens. Thanks again.

 

[ovnic1234]

Re: 1957 35 hp Johnson seahorse won't start

Picture number five: damage on the left side of the picture to the little square port looking thing. Not supposed to be mangled like that. You might be hunting a new head unless you can get it halfway back into shape and mated well to the block. Built up with JB weld?

Also check the block with a straight edge, where the two cylinder walls are almost touching in the middle can be a low spot, and you loose compression. I've had to lap the block ever so slightly before.

 

[HighTrim]

Re: 1957 35 hp Johnson seahorse won't start

My eyes are nowhere near that good, but looks like the gasket is damaged, not the head?

I too find low spots between the cylinder, especially on the head. Always seems to be the last spot sanded when dressing.

ovnic1234, gotta ask the story behind that pic! lol

 

[ovnic1234]

Re: 1957 35 hp Johnson seahorse won't start

Take a look at the picture again. Imagine the head is on the motor and someone has been prying on the bottom of the head. The little rectangular cooling passage is crushed in.

Chris, the picture: That's my father and I goofing around. He wasn't into it but my mother persuaded him to play along. He was trying to stop it from falling off his head that's why his hands are where they are. You can't see anything with one of those on. I was marvelling at how they kind of look like rejects at a Star Wars casting call. "sorry, you're too old, we're looking for a younger looking droid" Simple foolery.

Paul