1958 Johnson 18 hp starting issues

[Seemer]

OK - I just replaced coils, points, condensors and wires. Now for getting her started. I should add that I know nothing about this motor - a 58' Johnson 18 hp (FD-12). Here's what I have done without success.

1. Engine in neutral
2. pump the gas tank primer button (double line) until filter is full and button no longer presses in easily.....that's about 8 pushes.
3. pull out choke
4. pull start chord....pull, pull, pull
5. push choke in...pull, pull, pull

I get nothing.

Now I noticed that if I turn the throttle handle that there is a progressively widening fin under the magneto that bumps up against a rubber bumper which then connects to the carb. Where on the fin should that bumper be? The skinny part or fat part? Also noticed that when the choke is engaged, that bumper is pushed out away from the fin thing.

Please note that the carb is leaking fuel from the low speed needle....especially when I push the choke back in. Will this prevent a start?

Help!! Any ideas? I probably also need to check for spark...what is the best way to do that?

Thanks a ton.
Andy

 

[tmcalavy]

Re: 1958 Johnson 18 hp starting issues

Your procedure is almost complete, you should also roll the throttle over as far as it will go and then pull, pull...maybe twice. It has an advance limiter when it is in N.
Your carb needs to be cleaned/rebuilt...not too hard with the kit.

 

[Seemer]

Re: 1958 Johnson 18 hp starting issues

OK - Thanks. How about testing for spark without shocking myself? Can I just hold the plug or wire and watch for spark? Something tells me no.

 

[bktheking]

Re: 1958 Johnson 18 hp starting issues

Best way is using a spark tester, that way you can adjust the air gap. Using a spark plug can be deceiving, it will show spark but it's sometimes hard to tell how "strong" the spark is. Like TM said, rebuild the carb, probably half the battle.

 

[tmcalavy]

Re: 1958 Johnson 18 hp starting issues

You can get a good, inexpensive spark tester at auto parts stores or places like Harbor Freight...probably right here in the Iboats mall, too. I keep a test spark plug in the shop, it's electrode is bent out at least 1/4 of an inch. I plug it in to the boot, use a pliers with insulated grips to hold the electrode up against the block/powerhead with left hand, and pull it over with my right hand. if the igntn system is good, it will throw a fat blue spark across that gap. That's a basic test that generally works. Then there is spark under compression...there are testers that fit between the plug boot and the plug so you can test spark with the plug installed...even with the motor running, I think. Never used one of those, but sounds interesting.
If it is leaking from the high- (bottom) or slow-speed (top) needles, the packing around that needle is shot and needs to be replaced...which means the carb is old enough to need cleaning and service. Those carbs are very simple and generally easy to rebuild.