Old Johnson

[labrador-guy]

I pulled the muffler off this morning. I have never seen so much carbon in an engine before! It was caked in there like a chimney plugged with tar. It is gonna like some new gas and synthetic oil! Does this motor have a tell tale for cooling water? I found a 1/8" pipe plug on the bottom of the cylinder. Could a person drill a small hole in that plug for a tell tale? Do they pump water good? I know it is one of those forward motion suction type that don’t do well in a barrel.
Thanks for the info on the condensers Doug. Will check into that.

dale

[Mumbles]

That’s probably from using automotive motor oil back in the day. I was going to suggest cleaning it out and the bypass disc if it has one. The small holes in it get clogged with carbon making starting the motor a chore and poor idling. There’s no tell tale on these motors as you might lose the circulating water in the system if air can get in. It would be the same as a loose water tube connection. If you want to test the motor on a stand, you can undo the pipe plug under the cylinder and install an adapter for a garden hose. There’s no impellers in these motors to worry about!

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[bsplit]

If it ain’t broke……you know the rest….

[labrador-guy]

Guys, what color would this 1941 KD15 be? It is seamist green now and as I am cleaning parts, I think I am seeing silver underneath the green.

dale

[garry-in-michigan]

The pre-war color was semigloss aluminum. The Seamist green started in 1946 . . . 🙂

[labrador-guy]

Thanks Gary, you’re the best!

dale

[Doug Wilson]

if its running good may be ok for now, would say keep putting penetrating oil or mixture of atf and acetone eventually it should come off but have heard of flywheels breaking but its rare. took a long time to get the one off of my k50

Doug

how is it motors multiply when the garage lights get
turned off?

[labrador-guy]

Carbon build up is really bad on this KD 15. Something to check if working on one of these motors. 8to1 gas oil ratio and 40w oil sure made a mess in this one. I am trying to clean the down tube in the lower unit. I cannot get a wire down it yet. I am soaking it with gumout. Hope it loosens up over night. Probably better cleaners for carbon removal but, I am using what I have.

dale

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[The Boat House]

quote labrador guy:

Yup that is the baby! Mine does not have that kill button. It has two metal tabs that look like they contact the housing when the go lever is moved all the way to the left. What is going on with the exhaust damper? A leaver from the carb controls, opens a metal washer on the underside of the exhaust duct. Maybe exhaust relief? Your motor has a cutout on the muffler. Mine has a bolted on cover. Were these motors racers? Plenty thick oil ratio, maybe trying to seal the crankcase? This motor is a learning experience for me. I made an offer and it followed me home!
thanks dale

From what I have learned its a Johnson factory item.
Don’t know if it was an option you could order or
or what determined what motors they would be
installed on. So far I haven’t found any factory
literature that shows it.

[Mumbles]

With all of the carbon buildup inside, I’m betting the exhaust cutout was open all the time to keep your motor running!

[Author]

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