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Newbe buys 1958 Johnson 7.5 hp outboard

No clean the breaker points.----Set them at 0.020"-----Test for strong spark.----The stuff under your flywheel likely was renewed within the last few years !!
 
Looks like newer condensers. The original had a different cap. They are probably fine. Put a drop of oil on that cam wick. I also guarantee that the points pivot post was not lubed. You can put a TINY bit of oil on the top of that pivot pin. By capillary action and gravity, it will migrate along the pin and prolong your points life. I have been doing this for over 50 years and very rarely see any form of lube on these pivot pins. Some may argue that it's not necessary to worry about this minor detail, as the fiber/composite bushing will handle the wear.....but guess what? There is a HELL OF ALOT of pressure from the points spring pushing sideways on that pin and bushing. When I tune up one of these, I expect to never have to work on it for at least 20 years.
 
I have noticed most repairs on these .....although simple.....are incorrectly done. Everything that has been done, needs to be revisited in most cases.
 
Thanks for the advice. I still need to get new ignition cables before I put it back together. In the meantime, I took the carburetor apart and to my surprise it was clean as a whistle. Only the float looked somewhat beat up, but it still functions. Looks like you’re right, this engine was overhauled relatively recently.
 
If it has the cork float, put on a thin coat of clear epoxy.....fuel tolerant. I prefer the cork over the composite materials.
 
Ethanol gas makes a sticky mess out of the old cork floats that had a varnish coating.



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The float in the picture below was never in any ethanol gas and it still looked pretty good after 62 years in real gas.

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Great info, Rook. Ethanol has destroyed many great motors, even the 454 in my Chevy truck.....the stuff is poison to older equipment.
 
Mine looks more like to top one. Anyway, I have another question. I just got a new spring for the starter pull. How many turns do I need to give it before I align the arrow?
 
Spool your rope and see first, how many rounds it does. Then try adding 1 to 2 more complete revolutions to tension the spring. If it feels good, then leave it at that. As the spring breaks in, you may need one more wrap. It really is best, however, to create just enough spring tension to pull the rope back in all the way snuggly.
 
Ok, well, I’ve got the starter pull working well and I’ve replaced the ignition cables and spark plug boots. So the latest news is the pressure tank that I bought on eBay just arrived. It’s in OK shape, but I had a question about the primer pump. How far is that supposed to move? The one I have only moves up and down about 3/4”. Is that right? Seems to me that it should travel two or three inches to pump in enough air. It doesn’t seem to be working as it should.
 
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Sorry----The primer does NOT pump air.------It pumps fuel into the carburetor.---When motor starts it quickly pumps air ( crankcase compression ) into the tank to keep motor running!!
 
They only move 3/4" they pump gas into the carb. Then when motor starts, or as you pull it over, the air from the crankcase will pressurize the tank. These are very reliable pumps. See if it squirts out gas at the nipple marked "gas" at the tank.
Racer....we are posting together....you beat me by 2 minutes.
 
Oh I see. I thought it worked like the old kerosene lanterns, where you have to pressurize the tank by pumping the plunger 10 or 12 times.
 
It's easier to pump gas than pump tons of air into a nearly empty tank, right? Smart engineering. Even if the pressure tank would fail, you could still "prime" your way back to camp.
 
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