Old 50hp, new life.

[bonz_d]

Thought I would start a new thread as the other issue has been resolved. Thanks everyone!

1st the pictures.

Now for the story. This is a 1975 50hp Johnson that I've picked up to go on to my new project Alumacraft Classic 16. Found this while looking at another engine that was posted on craigslist that wasn't quite what I was looking for. When the guy told me he also had an old looper for sale we went and took a look. He also told me that he didn't know much about it as it came off a boat that he'd scrapped. How long it has been sitting is unknown.

So I first did a compression check that revealed 150psi on both cylinders which I was completely suprised and proved promissing. Next, checked for spark and there was none on either cylinder. Sad but not disappointed. So I went home to ponder this thing and decided why not if the price is right.

Is $100.00 the right price? I thought so.

Got it home and connected a start switch and battery and had spark for a bit and then it quit again. Over the weekend I went through and checked all the wiring and connections and couldn't find anything broken or loose so I tried it again and it now has beautiful spark on both cylinders.

Today I thought I'd give'r a go and see if it would start. Nothing. No spit no sputter, nothing. Then pulled the cover off the fuel pump and it was dry as an old bone. Tried to pump some fuel through it while the cover was off and still nothing. Pulled the hose apart and the end to the pump showed cracking and the hose was dry. Next came the hose connector at the shroud and discovered that it was completely block.

So that is were I am at with this so far. Tomorrow it's off to get some new fuel line and maybe a couple of carb rebuild kits. Then I'll see if the monster lives.

 

[1946Zephyr]

Re: Old 50hp, new life.

Looks like a steal to me. You did good. Keep on it. It sounds like you're getting things fixed up. 150 on each cylinder is excellent. I would say that motor has a lot of life left in it. Probably more left, than what was used in it. You might want to replace the impeller for good assurance too. I wouldn't want to see you burn this good ol' motor up.

 

[bonz_d]

Re: Old 50hp, new life.

Of course! Check the water pump. Just want to see if I can get fire to it and determine what else is going to need attention.
Preliminary check w/o it running it seems to shift ok into both forward and reverse but I think I'll need to see it run before I can tell for sure. Needs a good cleaning also as it's rather gummey uner the cover.

Yes I was really amazed when I took those compression readings. I was expecting them to be closer to 100lbs.

 

[bonz_d]

Re: Old 50hp, new life.

Just came in from the garage and I have to tell you that it purrs like a mean cat!

Not real familiar with this one yet but does anyone know if the tell tale is in the front of the exhaust housing just above the lower unit?

Now on to the next issue. It starts and runs very well but will not shut off with the ignition key? Wrong switch maybe?

 

[1946Zephyr]

Re: Old 50hp, new life.

Yea, it's possible that more wiring connections need to be cleaned up. As for tell tale, you might find a rubber hose going from the rear portion of the engine block to the lower shroud. Don't quote me on that, because my experience with this late of a motor, is pretty limited. I know water is supposed to come out the exhaust relief holes below the rear of the shroud.
To clean up the powerhead and de-grease it, I usually get a few cans of brake cleaner or carb cleaner. Spray it on and the grease runs off.

Good to see you got it running. Those are pretty darned good motors.

 

[bonz_d]

Re: Old 50hp, new life.

Went back out after looking over the wiring diagram for the switch and like a real dummy I found that I hadn't reconnected the black/yellow wire to the switch. Fixed that and tried it again. This thing popped right off. No hesitation at all. And now the switch works as it should.

Now my concern is when I shut it down there is a water stream coming from the front of the exhaust housing from a small hole. Also has water coming from under the exhaust housing swivel mounts. Is this normal? Must be pumping water as I can hear it drain back down.

 

[bonz_d]

Re: Old 50hp, new life.

Went to connect the throttle and shift cables this morning and ran into this problem. The posts that the cable ends connected to the 70hp had nuts and washers on them this 50hp only has the shift cable nutted. Is there supposed to be a clip on the throttle cable like there is on the smaller 35hp models?

 

[bonz_d]

Re: Old 50hp, new life.

Took the metal clip off another throttle cable end and gave it a try. Seems to be the answer! Working very well now.