Johnson 4HP

[ToolsnTrack]

My old man is into watter... boats in particular. He also likes a "bargain", something in boating circles which is unicorn-like in occurance. This wee outboard is one such example. Bought for a pittance and it shows.

He wrestled with it for a while but it is now with the Skunkworks. Not sure how many folk on here are into boat stuff, but I will be spending some time getting this wee lump recommissioned so might as well document it as I go..



So far I have it mounted on the bench and part stripped. For sure, it has no spark and the carb leaks badly, so some obvious hits for repair right there...

[usedabused]

Is it a seagull??

[ToolsnTrack]

You will have to forgive my industry ignorance... What's a seagull in outboard terms?

[collector]

Never let it run without the tail in water, if you do for a second of 10 the little rubber impeller who's responsible for the cooling of the engine is shot and therefore no cooling anymore. That results into since its a 2 stroke, a seized engine. No kidding it happens that fast !
The gap on the sparkplugs need to be real tight in order to get a wee little spark.
I have an 1970 chrysler 20 hp 2 cilinder 2-stroke outboard, bought for 75 euro, spend another 75 euro to get it running and is hanging in the shed since its okay. it didnt run in 4 years.
What i have done to it was 2 new coils and have eliminated the condensors and the points for an electronic replacement, this way i could bring it outside the flywheel and makes it easy interchangeble if it becomes faulty.
You will see the wooden post and at the ends i have taped the electronic point replacements.

[ToolsnTrack]

Nice!

So carrying on with the assesment, I started to address the ignition..



Lovely basic thing, cam on the centre shaft pushes each point into contact, that activates the coil, coil sends spark to HT lead underneath, lead to plug. Simples!

The coils themselves were the most obvious candidate for problems, so i took them off..



Plenty of gunk, but i suspect some of that might be the nasty melty stuff. Checked with a multimeter, and the primary windings seem ok... (loose wire to loose wire)



The secondary windings though, not so much (loose black to HT pin) as there is no conductivity through it. Ah, easy fault to spot. 2 new coils on order.

Up next, HT leads, plugs, cleaning the points then resetting!

[ToolsnTrack]

Coils ordered, onto the carb. Came with a chronic fuel leak, and a strip down of the carb revealed a few truths:

1. The carb is basic as bread.
2. Internally, it is in good servicable order
3. The gasket for the float bowl was cork, warped, and tragic
4. Replacements were import only, and horrendously dear.

Cue some Blue Peter-honed skills...



..voila! One home made gasket! Has it worked?



Yes, more or less. Carb holds fuel, I can hear the float moving so no hinderance internally. Even replaced the 4 mismatched screws for weatherproof bolts.

[taurus]

Jul 29, 2015 18:05:53 GMT ToolsnTrack said:

You will have to forgive my industry ignorance... What's a seagull in outboard terms?

A seagull is an old make of very simple outboard engine. Still plenty around since they were often used as an auxiliary engine so had very little use. Incredibly primitive little engines and some people collect them just for the fun of it.

As said, don't run it without the bottom of the shaft being submerged in water (a bucket will do). And don't underestimate the potential of so small an engine to cause you serious injury once the prop is turning. Keep any parts of your anatomy you are fond of out of harms way.

[ToolsnTrack]

Ah, cool! Every day is a school day. Yea, all testing will be done with the prop removed. I think I do have an oil leak down the shaft housing so a wee strip down of that once the engine is running may be needed.

[ToolsnTrack]

It was a pretty nice weekend, so I had a more relaxed tinker on the wee "Seagull". Fresh in the post came 2 new coils, so they went on and got aligned as best I could...



Continuity tested them through the secondary windings right to the plug end on the HT leads, so they are in good shape now. Cleaned up the points too. Still to check plug gaps and make sure they are on the right cylinders!

Other than that, I decided to clean up the casings a bit from the off wibblepoo NHS beige they were when it came in...



Here's the centre casing with the fuel tank now on. You can also see the magento flywheel back in place too. Gave it a hand crank and there is no fouling, so fingers crossed. Chose a different colour for the top casing:



...and painted on a little guide for the throttle lever seeing as the original sticker died. The gap, FYI, is the start point for pull-cranking...



...and there she is with the bottom casing. If I have time I may get some Johnson graphics just to break up the flat colours. Pretty happy with how its cleaned it up!

So, still to go: Test fire and make sure she runs, but before that I better strip down the lower drive for a look about... there is still a weep of oil down there from something.

[ToolsnTrack]

Stripped the lower drive down, transpired the oil "leak" was in fact latent oil sat in the bottom of the exhaust chamber. Following a decent scrub it seems to be cured.



All that was left to do was fire it up...



Job jobbed! Oh!, apart from the decorations... Amazing the difference some period logo makes.

[sunbuilder]

I had one of these that the sea scouts had had in a cupboard for many years unused. don't forget to change the water pump impeller in the leg.
it is a service part and pretty cheap and very easy to do. when left for a long time they tend to initially work and then after a short while break up in to pieces.

[taurus]

Sweet - nice little engine.