I was given a 3 hp Johnson yesterday, a friend of my dads bought it at an estate sale about 10 years ago where it sat by his shed since. Its from the 60s or possibly the 50s, the serial number and model number are clearly visible, the starting instructions say to move the magneto position to start, then choke it, thats why i figured it was so old. Its a 2 cylinder, only bad thing is its been sitting with one of the spark plugs out, no doubt it has moisture inside, and it doesnt spin over when i pull on the rope. I'd like to call Bombardier, try to get the build date on it and see if parts and a manual are still available, then try to free up that stuck cylinder with some MMO. If I succeed in that I'd then like to tear it completely apart(engine, foot, etc) and rebuild it, give it a good paint job and have a nice working vintage motor. It has a self contained metal gas tank, it must have been dropped at one point as one side has a big dent in it. Most if not all the bolts will have to be soaked in some kind of penetrant before I even attempt to take anything apart. It was made in Belgium. So, were these some good little motors, and were the belgium made ones just as good as the OMC American made ones?
3 hp Johnson
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Belgian used to make awesome cars, like Minerva.
More seriously, this thread needs pics!
More seriously, this thread needs pics!
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$50 site donor 2024
I think you have a nice nostalgic decorator piece for around the camp if left original.
After all the time and money spent - what would you power up with something that weak ?
After all the time and money spent - what would you power up with something that weak ?
Don't take it apart until you are sure you can get gaskets for it.
From that time period it probably is a 2 cycle, so you would want to run gas with a 2 cycle oil mix.
From that time period it probably is a 2 cycle, so you would want to run gas with a 2 cycle oil mix.
3 HP would be a nice engine for many sailboats.
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$50 site donor 2024
Maybe a newer 3 hp - don't trust the wind that much
It'll be fine for rental boats on small lakes and such. 3 HP from back in the day was more like 6 HP today. Lots of torque for a small motor. Just not as many RPM's. And it's TQ x RPM that makes the HP formula work. W/o the higher RPM, it "only" rates 3 HP. But it'll push a little 14 footer right along. It won't plane, but it'll move just fine
Prolly dropped the spark on one cylinder is why they pulled the plug. Could not figure out why it was not sparking and let it sit.
Put it down with carb side down and fill the stuck cylinder with Liquid Wrench. Wait a week and try to turn it again by hand. You can take the tank off to get access to the flywheel.
Very likely that it lost a coil ... That's why the spark went away and they started fooling with it. Coils can be found for these old motors. Just need to get a parts diagram so you can search by actual part number.
Many old dealerships are being bought out and "updated". Their old inventory is coming up on eBay all the time. Get BRP to give you the dates and such. Search for a parts list first. Then get what you need
Prolly dropped the spark on one cylinder is why they pulled the plug. Could not figure out why it was not sparking and let it sit.
Put it down with carb side down and fill the stuck cylinder with Liquid Wrench. Wait a week and try to turn it again by hand. You can take the tank off to get access to the flywheel.
Very likely that it lost a coil ... That's why the spark went away and they started fooling with it. Coils can be found for these old motors. Just need to get a parts diagram so you can search by actual part number.
Many old dealerships are being bought out and "updated". Their old inventory is coming up on eBay all the time. Get BRP to give you the dates and such. Search for a parts list first. Then get what you need
This was the first OB I ever had, great motor, and parts should still be available. Many engine electrical parts were common with other OMC motors.
The oil / gas mix when new was 16-1 !!! I would guess 25-1 would be OK.
One thing to remember, the cork float in the carb was coated with shallac, shallac is soluable in alcohol. You may want to re-coat the float with epoxy.
The oil / gas mix when new was 16-1 !!! I would guess 25-1 would be OK.
One thing to remember, the cork float in the carb was coated with shallac, shallac is soluable in alcohol. You may want to re-coat the float with epoxy.
+1 Recoating all OMC cork floats with epoxy is a must now days. Carb or fuel tank gage ...
To RTexasF, I was not intending to imply this motor would make the equivalent of modern outboards at the prop. It won't wind that high. Modern 2-stroke outboards get their HP with motors that wind 5,500 to 6,500 RPM. And HP is a function of RPM in the calculation, whether measured at the crank or the prop ...
But the cylinder displacement is on the order of what a modern 6HP is, and therefor the torque will be about the same at say 2,500 to 3,500 RPM. This old motor will likely sign off at 4,500 - just when modern motors are really waking up. But in the mid-range, it will be surprisingly torquey and will move a light skiff nicely
To RTexasF, I was not intending to imply this motor would make the equivalent of modern outboards at the prop. It won't wind that high. Modern 2-stroke outboards get their HP with motors that wind 5,500 to 6,500 RPM. And HP is a function of RPM in the calculation, whether measured at the crank or the prop ...
But the cylinder displacement is on the order of what a modern 6HP is, and therefor the torque will be about the same at say 2,500 to 3,500 RPM. This old motor will likely sign off at 4,500 - just when modern motors are really waking up. But in the mid-range, it will be surprisingly torquey and will move a light skiff nicely
yes guys I need to get into the 21st century and make an account to post pics on here lol. what site do yall recommend? photo bucket? what would i power with something that weak? a 10 ft aluminum hull that I've been having forever, perfect for it. It doesnt matter to me if an engine is gas or diesel, (i prefer diesel) 1 hp or 1,000 hp, I can find a use for it. I'm going to an early labor day bbq I'll make a photo account when I get back tonight
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Originally Posted By: mobilaltima
yes guys I need to get into the 21st century and make an account to post pics on here lol. what site do yall recommend? photo bucket? what would i power with something that weak? a 10 ft aluminum hull that I've been having forever, perfect for it. It doesnt matter to me if an engine is gas or diesel, (i prefer diesel) 1 hp or 1,000 hp, I can find a use for it. I'm going to an early labor day bbq I'll make a photo account when I get back tonfight
I don't think it is you that needs to get into the 21st century.
Most other sites seem to allow pics, they add a lot of value to a post.
I have in the past posted pics here, but it really is a hassel.
Funny thing with your 3hp, the prop points down at an angle.
Never figured that out.
yes guys I need to get into the 21st century and make an account to post pics on here lol. what site do yall recommend? photo bucket? what would i power with something that weak? a 10 ft aluminum hull that I've been having forever, perfect for it. It doesnt matter to me if an engine is gas or diesel, (i prefer diesel) 1 hp or 1,000 hp, I can find a use for it. I'm going to an early labor day bbq I'll make a photo account when I get back tonfight
I don't think it is you that needs to get into the 21st century.
Most other sites seem to allow pics, they add a lot of value to a post.
I have in the past posted pics here, but it really is a hassel.
Funny thing with your 3hp, the prop points down at an angle.
Never figured that out.
Weedless prop
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