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2000 Johnson 50hp Model J50PLSSM

Jupiter Dinghy

Jupiter Dinghy

Regular Contributor
Hi folks,

I am looking at a cool restored antique (MFG boat from the 60's) that has the motor listed above.
Looks like it has very low hours and used in fresh water as I can't seem to find one corrosion spot anywhere inside or out.

I am getting confused by some internet posters who own this model and mention an "external oil tank", because I can't recall seeing any external oil tank upon checking it out visually.

Is this an oil injected motor? Or does it run on 50:1 like 99% of the other 2 stroke?

Also, if I go forward with this one, is the Seloc service manual worth purchasing? It's the only one I see at a "reasonable" price, but it lists so many models 2 & 4 stroke, that it makes me wonder if it can be any good on any specific (or all) of these models?
 
The service manuals that cover an assortment of models is confusing to say the least. Bite the bullet and pay whatever is required for the specific manual for that specific engine. It'll pay for itself the first week When/If you decide to sell the rig, the manual goes with it and is a selling tool!
 
scalhoun506 said:
parts lists on this site show VRO or old style fuel pump.
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Thanks.

joereeves said:
The service manuals that cover an assortment of models is confusing to say the least. Bite the bullet and pay whatever is required for the specific manual for that specific engine. It'll pay for itself the first week When/If you decide to sell the rig, the manual goes with it and is a selling tool!
Click to expand...
Thanks Joe. That's what I kinda figured based on past experience of a "multi-model" manual...

racerone said:
How did you arrive at this fact------" 50:1 like 99% of the other 2 stroke " ?
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Yeah, I take that back. After looking that up closer, I realize there are actually more oil injected 2 strokes than I thought there was.
On that tangent, and aside from the extraordinarily expensive E-Tec's, are there still any 2 stroke in production anywhere by major manufacturers?
 
kevinj said:
A 2000 Johnson 50HP should have a VRO for automatic oil mixing and use a remote oil tank for the supply. If there is no remote oil tank, then that means a previous owner has either blocked the oil side of the VRO fuel pump or they have replaced it entirely with an old style fuel only pump. Either way, if it is now a pre-mix you'll use a 50:1 ratio.
Click to expand...

Thanks Kevin, and would the oil reservoir be on the power head under the cowling?
I can't find ONE pic or exploded view for this motor showing an oil reservoir, hence my confusion.....
 
Funny... doing some research on the topic I found this old thread (2012) where on post # 6 someone had the very same question and wondered about the oil injection feature as he could not see it on his motor (same model) and later in the thread he mentions the VRO having been bypassed, which confirms your assertion, Kevin:
http://www.marineengine.com/boat-forum/showthread.php?399392-2000-50hp-johnson-oil-injection-bypass

I guess for the "comfort level" thingie put forth by Joe on this older thread, I would probably feel as good, if not better, making my own mix as usual.....
 
Thanks racer. I guess a bunch of those have been bypassed by their previous owners to stand clear of nightmare scenarios with failing VRO's / horn.
 
The VRO has an oil pump component and pulls oil into the mixing chamber.----It would need an oil hose from the tank to the VRO pump.
 
racerone said:
The VRO has an oil pump component and pulls oil into the mixing chamber.----It would need an oil hose from the tank to the VRO pump.
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Thanks, and that settles the score then, since the motor I saw was started with only the fuel hose connected to it, confirming the VRO has been bypassed...
 
The VRO, if still installed and bypassed so as to simply be used as a fuel pump, would be a hellava big ugly black plastic unit with one fitting on top that leads to the carburetor(s)... and three fittings on the bottom... one that leads to the crankcase to operate it, one for fuel, one for oil (plugged hose at some point).

If this unit doesn't exist, someone has no doubt installed the regular smaller fuel pump. In either case, premix (50/1) is required.
 
joereeves said:
If this unit doesn't exist, someone has no doubt installed the regular smaller fuel pump.
Click to expand...
That's what happened Joe. Here is the fuel pump:
2crwryw.jpg


Incidentally, you may be able to tell me what this threaded hole on the cylinder head is (see arrow)?
21eahht.jpg
 
Joe, on the model at hand here, is this the proper carb adjustment procedure?:

(Carburetor Adjustment - Single S/S Adjustable Needle Valve)(J. Reeves)Initial setting is: Slow speed = seat gently, then open 1-1/2 turns.Start engine and set the rpms to where it just stays running. In segments of 1/8 turns, start to turn the S/S needle valve in. Wait a few seconds for the engine to respond. As you turn the valve in, the rpms will increase. Lower the rpms again to where the engine will just stay running.Eventually you'll hit the point where the engine wants to die out or it will spit back (sounds like a mild backfire). At that point, back out the valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest slow speed setting. Note: As a final double check setting of the slow speed valve(s), if the engine has more than one carburetor, do not attempt to gradually adjust all of the valves/carburetors at the same time. Do one at a time until you hit the above response (die out or spit back), then go on to the next valve/carburetor.It may be necessary to back out "all" of the slow speed adjustable needle valves 1/8 turn before doing the above final adjustment due to the fact that one of the valves may be set ever so slightly lean.When you have finished the above adjustment, you will have no reason to move them again unless the carburetor fouls/gums up from sitting, in which case you would be required to remove, clean, and rebuild the carburetor anyway.
 
Thanks Joe, and sorry for the late reaction, been out of broadband services for a few days.
To be forgiven, here are a few pics of my "new" 1964 MFG Westfield Deluxe with the motor in question:

2vkgpc3.jpg

70j67l.jpg

auvz1v.jpg
 
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