Johnson seahorse 35hp siezed

[Fourscoot]

Well, its a free boat kinda cool the age and all. I think it is a 1957-58 model engine. The boat and engine have been parked in the garage of my folks for over twenty years. It ran when it was stored. After pulling out and cleaning upI tried to turn the engine over but nothing. The engine won't turn by hand or with the starter. I know there is work to be done with other parts such as carbs and such. First I want to see if I can get the engine to spin.

Any suggestions?
Thanx, Scott

P.S. does any one have a pdf version of an engine diagram?

 

[samo_ott]

Re: Johnson seahorse 35hp siezed

First, find the model # on the transom and post.

Next to try and unseize: Remove plugs and put the engine so that the plug holes point straight up. Pour in Marvel mystery oil, 2 stroke oil, PB blaster, etc into the holes liberally. Remove the pull start and put a wrench on the flywheel nut and try and move back and forth gently... Keep putting oil in... could take days... or longer... But watch as it will leak out the carb and/or exhaust, so put rags down... Try this for awhile. I've had it work and not work... So see what happens...

 

[Fourscoot]

Re: Johnson seahorse 35hp siezed

I started to use marvels today. Will the pull start unwind if removed? I'll post the model and serial number tomorrow. Thanks

 

[tmcalavy]

Re: Johnson seahorse 35hp siezed

The pull start won't unwind...it comes off as a separate unit. Twenty years? Hmmm...was it sitting there with the spark plugs out? That allows moisture/rust to get into the cylinders. If it was stored with the plugs in, there's a chance you can free it up...using the method mentioned. Hope you didn't smoke the starter trying to start it. Shine a flashlight into the plug holes...if you see brown/rust it may be a lost cause.

 

[Home Cookin']

Re: Johnson seahorse 35hp siezed

I've also heard of people putting a wooden dowel in the spark plug hole for the "up" piston and tapping it with a hammer. Others with more knowledge than I can comment on whether that's a good idea.

 

[Chinewalker]

Re: Johnson seahorse 35hp siezed

It is really not a great idea to unseize a motor and then run it unless you've done at lease a partial tear-down to inspect the bearings along the crankshaft. You may free up the motor, but if any one of the bearings is compromised by rust, then the motor likely won't last very long. I know there are folks who will swear their motor is "fine" and has been running for years after being stuck, but I've too many motors have a catastrophic failure that could have been prevented by a closer inspection...

 

[Fourscoot]

Re: Johnson seahorse 35hp siezed

Well, I think it is a mute point as marvels mystery oil has failed.

Here is the information from the motor: RD-19C 1737236 Johnson Seahorse 35

Any Information on were to find parts and a diagram of hte motors would be nice, as I will be tearing it down.

Thanx everyone

 

[tx1961whaler]

Re: Johnson seahorse 35hp siezed

www.outboardbooks.com

 

[Fourscoot]

Re: Johnson seahorse 35hp siezed

Does anyone know where a good place to buy a full rebuild kit from?

 

[Willyclay]

Re: Johnson seahorse 35hp siezed

I scanned and saved the non-factory service manual that I used to completely rebuild a seized 1959 Johnson 35HP. It covers all 30-40HP outboard motors built by OMC from 1956-1964. Send me a Private Message with your email address and I will send you a copy of the manual as an attachment. Good luck!

EDIT: It is a pdf file.

 

[tmcalavy]

Re: Johnson seahorse 35hp siezed

Might be simpler to buy a complete replacement powerhead, unless you're sure of what you've got with the seized powerhead. Either way, try the free classifieds at www.aomci.org