50's Johnson Seahorse Doesn't Want To Come To Life

[JPBJustin]

Recently Aquired a Johnson Seahorse 3HP JW-10 model, which I believe puts her around '52-'54 era. The thing sat in a garage for quite a while. I'll go ahead and list out what I've done.
-Removed carb and gave it a good cleaning.
-Went ahead and gave the tank a good cleaning as well, including stone filter.
-Bought the carb kit and replaced seals and such.
-Pulled both spark plugs and confirmed there was at least something that would start a fire. (Blue sparks enough I'd assume?)
-Pulled off the top and checked out the ignition guts. Coils, points and probably condensors all looked like they could be replaced, but as I said there was a spark there.
So we tried to start the thing, and just got no reaction from her. Sprayed starter fluid right in her, and nothing. A little squirt of gas on the plugs and nothing. Rechecked for spark, cause my buddy who showed up to help didn't believe there was spark. Engine appeared to have compression. Anyone have any ideas? I'm already expecting to get a lot of advise on replacing the ignition parts up top, because as I said they need it. However, there was spark there, so without any reaction at all from the thing I would have a difficult time dumping around 75 bucks just to get a better jolt. Let me know what ya think.

 

[nwcove]

Re: 50's Johnson Seahorse Doesn't Want To Come To Life

compression numbers! and dont use starting fluid! borrow or buy a tester.

 

[freddyray21]

Re: 50's Johnson Seahorse Doesn't Want To Come To Life

there is spark and there is spark. Spark should jump at least a 1/4 inch on a tester. weak spark will show good across a plug, but not be hot enough to fire under compression. If you have spark, but weak then the condenser is most likely the culprit. If the coils are not cracked they are rarely ever bad and points and be cleaned and regapped.

 

[kfa4303]

Re: 50's Johnson Seahorse Doesn't Want To Come To Life

Hi JPB. Welcome to iboats. There are a couple cheap tricks you can try to see if you can get her running a bit. As the fellas already mentioned, compression is key, you probably want around 50+ psi per cylinder and they should be within 10% of each other. You can get a tester at Harbor Freight for like $20, or from an auto parts store. Assuming the compression is ok, try cleaning the points with very fine grits sandpaper until shiny and resetting them to .020" with the rocker arm of the points in the TOP position. Check the coils for any signs of damage while you're under the flywheel, chances are they've already been replaced by a previous owner over the years, in which case they're probably ok, but if they're original, or damaged in any way, they'll need to be replaced. Eventually you'll want to replace the s'plug wires, but you said you have spark, which is a good sign, and cleaning the points should help a lot. When you rebuilt the carb did you remove the welch plugs? If so, good, but if not you want want to remove and replace it, or thoroughly re-clean the lo speed passage. If you're sure the carb is clean try setting the lo/hi needles according to the link below. You'll need to dial in a proper idle and hi end on the water, but this will get you close. When you try to start her again be sure you're in a test tank. You can't use muffs on these older models. Also, spray a little 16:1 fuel/oil mix into the cylinders before you reinstall the spark plugs then give her a few pulls. Hopefully, the cleaned and re-gapped points, fresh, proper fuel oil mix and buttoned up carb will at lest get her to sputter a bit. Here's a link to a parts manual with exploded diagrams. It's for a '55 JW-11, which means you atually have a '54, but it should it help some. Gi e the links a read a report back. Good luck.



http://forums.iboats.com/showthread.php?t=167352
http://forums.iboats.com/showthread.php?t=158086
http://www.marineengine.com/parts/v...ntage-evinrude-johnson/376399/37639900001.htm
http://www.duckworksmagazine.com/07/columns/max/index1.htm

 

[JPBJustin]

Re: 50's Johnson Seahorse Doesn't Want To Come To Life

Just an Update here. After playing with the old Johnson as described above, it just so happened to be that my father had left a '72 Evenrude 4hp motor at the same guys garage I was working on the Johnson at. Go figure. After looking at the top end of the Seahorse and the top end of the '72 we all realized they appeared to need the same ignition tune up. The advice I was given was to put the money into the "newer" motor, so that's what I've been doing. I want to give more details, but I was wondering if it would be something that I should start a new thread on? Also, I've been using the information given here for the Seahorse for the '72 and wanted to give a thanks to all who helped.

 

[kfa4303]

Re: 50's Johnson Seahorse Doesn't Want To Come To Life

Hi JPB. IMHO I wouldn't put money into a "new motor". You can rebuild the entire ignition system in these old OMC motors for less than $100 in one afternoon and do all of the work yourself. That's why most folks around here prefer the older magneto style motors. That being said, I would start a new thread for the new motor. Although, I'm sure some folks here in the forum will take those old gems off your hands if you really don't want them.