1964 Johnson 3hp Model JH19A Serial # 101739 Rebuild

helicopterjohn

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Hi Indy46,

First thanks for your valued input.

I don't know the history on this engine but based on how the engine came apart I doubt it was a salt water motor. I believe it has sit for many years without running and that was the main problem. All the bolts came loose without any issue i.e. broken bolts. The foot has no corrosion and even the bolts at the impeller area came right out with no issue. The inside of the the exhaust housing also looked corrosion free. Thanks for the point gap information. I will have to take a closer look at the coil laminations to see where they line up with the mag plate.

I am waiting on a few parts that are due in next week. While I am waiting on the parts I will tackle the ignition system, cleaning it up getting rid of all the rust and goo and order and replace parts as necessary. I have no idea what the goo is on the cam. It has probably been there for 20 or so years. Ha Ha

John
 

helicopterjohn

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Hi Chinewalker,

Thanks for the valued input.

Yes, I need to do some research on the part numbers on the points and condensers and get some on order.

John
 

helicopterjohn

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Hi Chris,

WOW! You guys are the best. I really appreciate all the information and help you guys have given me.

I found a parts motor and it had a really nice looking reed valve plate so that takes one thing off of my to do list.

I will try those tests you described when I take the ignition system apart for cleaning.

How long to you soak your parts in Pine Sol?

John
 

HighTrim

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Then,

after your ignition is all set, your carb is cleaned installed, and static setting of low speed needle, you need to linc n sync.

See the attached picture.

When your speed control lever is within the dotted line, or 2 embossed dots, your throttle plate should just start to open. To accomplish this, there is a brass cam attached to mag plate with 2 bolts. Look from underneath. Loosen the bolts. Put speed control lever between those 2 dots. Now pull out cam, or push in, so that it is just touching the cam follower at this point after taking up slack. Re tighten the bolts and you are done!JW carb timing.PNG
 

oldboat1

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If new to magneto work, it's a good idea to do one side at a time so you have the other side to check for assembly. The relevant condenser and set of points are to the right of the coil. To replace plug wires, the plate needs to be lifted off and flipped over -- wire placement is self explanatory. They should be 7mm solid core wires -- check at NAPA stores, or maybe cycle or small engine shops (maybe farm implements -- think old tractors use the wire.) Make sure the wire core makes solid contact at the coil and with the spring connector in the plug boot. Also want to be sure the wiring is tucked in during final assembly so as not to engage the spinning flywheel.

There's an interesting video instruction describing the coil testing mentioned earlier: http://www.penn.itgo.com/video-pages/coil-testing.html (Worth checking.)
 

helicopterjohn

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Hi oldboat1,

Thanks for your input.

When you say solid core wires, do you mean a stranded wire or do you mean carbon impregnated type fiber?

I tried your supplied link but was unable to get it to work. I did a little searching and found this link to his YouTube video. https://www.youtube.com/watch?v=KT8rk5QWgS0


Here is another link where it shows you how to check for spark. https://www.youtube.com/watch?v=qJwY0heWa2A

I have one of those spark testers and it is an invaluable tool when working on small engines. A friend of mine bought me one at Harbor Freight and gave it to me as a present.

John
 
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lindy46

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Tune-up kit for your motor is OMC 172522. Includes points and condensers.
 

helicopterjohn

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Hi Hightrim,

I just checked the coils and they both tested good. I will order some new points and condensers and the ignition system will be ready to go back together.

Hi Lindy46,

Thanks for the tune up kit number.

John
 

helicopterjohn

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Carb. Update:

I finally got my Carb Kit 439071 which included a new float. I did some additional cleaning i.e. removed the welch plug on the low speed needle circuit and cleaned the 4 holes shown in the pictures. I also used my trusty flashlight shining through the holes to verify that they were cleaned properly. Sorry, the flashlight beams in some of the pictures did not show. I guess it was because of the flash on the camera. If you look at the pictures you will see that I also verified that the low speed needle seat was cleaned. The low speed needle was also smooth and clean and had no groves that might impede the flow of fuel. Furthermore, I attached a picture of the high speed jet with the inspection plug removed. The Carb. is now ready for re-installation on the motor.

1964 Johnson JH19A 3hp Low Speed Welch Plate Removed For Cleaning



1964 Johnson JH19A 3hp Low Speed Jet - Not Visible In Picture Is The Cleaned Low Speed Jet Hole From Flashlight Beam



1964 Johnson JH19A 3hp High Speed Jet - Not Visible In Picture Is The Cleaned High Speed Jet Hole From Flashlight Beam



John
 
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helicopterjohn

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1964 Johnson JH19A 3hp part # 205574 flange



The lower end of my crankcase on my Jh19A engine has a recess where this goes in. There is not seal on this piece and I wondered what the purpose for having it there. I purchased a used JW14 3hp power head for parts and that area on the back of the lower crankcase was flat. My flange will not fit on the Jw14 engine because that flange sticks out. All the other mounting holes are the same. Just wondered if I ground off the flange would it hurt anything????? The motor has about 70 PSI compression on both cylinders and would possibly be a good engine except that the internal splines on the bottom of the crankshaft are ruined. I know there are used crankshafts out there and this might make a good powerhead if the crankshaft was replaced.

Any input would be appreciated.

John
 

oldboat1

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would think that protrudes up through the gasket (0312946) giving you a flush seal(?).
 

helicopterjohn

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Hi oldboat1,

Thanks for the input.

I originally thought that, but there is no sealing surface on either the splined shaft that enters the crankshaft or a seal the fits on the end of the protruding flange that fits into the lower motor housing. Not a big deal at the moment as I am going to try install a couple of pistons in my present motor. The piston and head gasket are at the local post office and should be delivered tomorrow.

John
 

helicopterjohn

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Update:

1964 Johnson JH19A 3hp Gasket Set

A friend of mine has a CNC Gasket Cutting Machine. I think it is called a Cricket. I scanned the old gaskets on my Epson 545 Printer. He converted the files from Jpeg to a file that was readable by his CNC Gasket Cutting Machine. I purchased a roll of 1/32 thick gasket material at Advanced Auto Parts and he cut me a couple of sets for my engine.



1964 Johnson JH19A 3hp Magneto Plate Top Side With New Points And Condensers

I received the new points and condensers today. The only issue was that the new kits which were supposed to be made in the USA had a 3mm X .50 thread where the wires hook up to the points. The old points had I believe a 6/32 USA thread. Of course, the new point sets didn't come with new screws, so it is another trip to the local Ace Hardware. My buddy even powder coated the throttle lever for me. Ha Ha Looks a lot better than the original photos on the tear down shown on page 2 of this thread.



1964 Johnson JH19A 3hp Magneto Plate Bottom Side

I took the brass cam plate off and freed up the bolts and gave it a little polish on the 3M Scotchbrite wheel. It is now freed up and ready to adjust during the link and sync procedure.



Well, most of the dirty work is done and now comes the time for re-assembly.

I finally received what I believe are all the necessary parts to re-assemble the short block. Another friend of mine has a small brake wheel cylinder hone. He put a nice cross hatch pattern on the cylinders. Just need to give all the parts a good cleaning and then wash them in Tide detergent to get them really clean. That is a procedure he uses when building his NHRA Drag Car engines. He also built the motor for my 1966 Ford Cobra Kit Car.

John
 
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lindy46

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Are those old spark plug wires? If so, I'd replace them. Looks like the top coil wire is pulled out from the coil.
 

helicopterjohn

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Hi Indy,46,

Thanks, I will take a look at the plug wires

Question: The felt wiper that lubes the cam was gone. I am looking for a picture with one correctly installed. I got 2 new pieces of felt with the points and condenser kit. I only see one bracket to hold the felt. Guess they shipped a spare.

Never mind I took a closer look at the picture posted by HighTrim on page 2 post 24 and found my answer.

John
 
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helicopterjohn

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Hi racerone,

First, thanks for the valued input.

I believe you are talking about the 510289 grommets. (2 each) WOW $11.00 each. I would imagine the purpose is to keep moisture away from the internal screw connection to the plug wire. I will probably just use some Marine GOOP which makes a nice seal but is easily removable in case the plug wires ever need to be replaced.

John
 

racerone

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Those coils come with new boots.----Perhaps someone said---" don't need them " and tossed them out.
 
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