1973 Johnson seaking 20 hp

[chiefcatchemall]

Re: 1973 Johnson seaking 20 hp

Alright well I got the flywheel off. By just looking at the primary coil under the flywheel it dont look right. Looks like the plastic melted off of it. But what I dont understand is why Id get spark everytime out of the top cylinder and only once in a while out of the bottom cylinder...If the primary coil was bad wouldnt that make both of them not get spark?

 

[chiefcatchemall]

Re: 1973 Johnson seaking 20 hp

Does it look fried to you guys? I was talking to a couple guys and they said they put that waxy crap on the bottom because thats where the wires come out of the coil and its used to protect them. Anyways I put it back on replaced the condensers and points and I got great spark on both cylinders. First pull loud pop (backfire) like it was gonna run then nothing after that...just like before. I got great spark compression and fuel....Sooo lost right now...After trying 20 times or so I pulled the plugs and they were dry...The other day when I was pulling it over without success I pulled the plugs and they were wet like they should be....I have nooo idea....

 

[Howard Sterndrive]

Re: 1973 Johnson seaking 20 hp

if you haven't already, buy 2 new spark plugs
I scanned over this thread, and see no mention of changing the plugs.

After that, here is an interesting read: http://forums.iboats.com/showthread.php?t=279981

 

[Sea18Horse]

Re: 1973 Johnson seaking 20 hp

Well, if now you have a good fat spark that will jump 1/4 '' at least and the plugs are dry then I'd say the next thing is to look at the carb. You might try getting a spray bottle with some premix in it and see if it will run for a bit on that. Then you'll probably need to overhaul the carb. Good luck! Sounds like you're getting there!

Cheers...................................Todd

 

[chiefcatchemall]

Re: 1973 Johnson seaking 20 hp

well when i unscrew the screw in the bottom of the bowl gas comes out so there is deff gas in there...

 

[kfa4303]

Re: 1973 Johnson seaking 20 hp

Glad you're getting gas chief. I was looking at your last pic again. It looks like you still have the old, original power coil. While it may be ok, I would replace it with a modern one and hold on to the old one, if need be, just to be safe. Sounds like you're getting closer to having her run. Make sure your carb is nice and clean so that the fuel in the bowl can actually get to the cylinders. Make sure that the Lo/Hi speed needle passages are super duper clean. You're almost there.

 

[chiefcatchemall]

Re: 1973 Johnson seaking 20 hp

Ripped the carb off for the second time for a cleaning. I sprayed all the jets with carb cleaner and now its out in a bucket soaking for a while. Gonna pull it out in a few more hours and let it dry. Picked up a can of compressed air (9 bucks!) and gonna spray all the jets after its dry. Hopefully itll do some good...

 

[chiefcatchemall]

Re: 1973 Johnson seaking 20 hp

Also I noticed it is harder to pull over now since I replaced points and condensers yesterday. What could cause this? The flywheel not too loose before?

 

[Sea18Horse]

Re: 1973 Johnson seaking 20 hp

Ripped the carb off for the second time for a cleaning. I sprayed all the jets with carb cleaner and now its out in a bucket soaking for a while. Gonna pull it out in a few more hours and let it dry. Picked up a can of compressed air (9 bucks!) and gonna spray all the jets after its dry. Hopefully itll do some good...

So you say you took it off and sprayed out all the jets. Did you also take it completely apart? Remove all the jets, needle(s), seats, core plugs and float? It really needs to be disassembeld completely, cleaned, blown out and reassembled with a new gasket kit and maybe a new float for it to be effective.

Also I noticed it is harder to pull over now since I replaced points and condensers yesterday. What could cause this? The flywheel not too loose before?

Replacing just points and condensers shouldn't have had any effect on that. You're sure the flywheel key was/is ok? And you torqued the flywheel down correctly before trying to start it? Nothing dragging when you spin it over by hand with the spark plugs out? Very odd!

Cheers..........................Todd

 

[chiefcatchemall]

Re: 1973 Johnson seaking 20 hp

the key seemed good to me Todd...a tiny scrape in it. Nothing that would effect it. I torqued it to 40 ft/lbs

 

[chiefcatchemall]

Re: 1973 Johnson seaking 20 hp

Just put the carb back together. Tried to start it up. Didnt even sound like it wants to go. Threw new plugs in it too...I AM LOST!

 

[AlTn]

Re: 1973 Johnson seaking 20 hp

are you certain you put the ignition wires back on the proper plug?....by spraying fuel mix into the carb throat you should at least have the motor try to fire....with the carb inverted, was the float parallel with the carb body?..with the carb assembled, can you blow into the fuel intake barb with the carb upright and with the carb inverted you cannot?

 

[chiefcatchemall]

Re: 1973 Johnson seaking 20 hp

I bought a spark plug tester. I am getting great spark on the bottom now but a very weak spark on top. Replaced condensers and points the other day. So not that. Cannot be the main charging coil under the flywheel because I am getting a spark on both. So my guess would be a weak ignition coil on the top cylinder. I am going to go out and swap the bottom with the top and see. That should let me know if that is my problem.

 

[kfa4303]

Re: 1973 Johnson seaking 20 hp

I think you're on the right track chief. Double check the spark plug wires to make sure they're hooked up properly too.

 

[chiefcatchemall]

Re: 1973 Johnson seaking 20 hp

Yeah they are hooked up correctly. I just swapped the wires at the connecters on the coils. Put the bottom wire leading into the bottom coil into the top coil. After I did that I got great spark on the top and nothing on the bottom. So the problem was reversed. So that tells me that both ignition assembly coils are good. So I am assuming that either the wiring coming out of the top coil is bad or the points arent gapped correctly that the top coil wires lead to.



Any input?

 

[Sea18Horse]

Re: 1973 Johnson seaking 20 hp

When you set the points did you rotate the crankshaft around so that the points rubbing block was in the correct position for each one? Often the points cam will have an area on it marked "set" or "top". But in general the rubbing block should be at the highest point on the cam , usually this is aligned with the keyway. If you did then yeah the wiring between the power coil and the secondary coils is about all that's left. Good luck!

Cheers..................Todd

 

[Howard Sterndrive]

Re: 1973 Johnson seaking 20 hp

if not the charge coil, it can be a weak magnet in the flywheel. you can read that thread I linked to about adding a second trigger coil in parallel.

 

[chiefcatchemall]

Re: 1973 Johnson seaking 20 hp

Set the points in accordance to where it says on the crankshaft. If i set it like it says the one point closest to the crankshaft is slightly higher than the other point. Slightly offset. Also When I put the flywheel back on and torqued it, when I go to pull it over the flywheel wont move?...Didnt have that problem last time

 

[Sea18Horse]

Re: 1973 Johnson seaking 20 hp

Set the points in accordance to where it says on the crankshaft. If i set it like it says the one point closest to the crankshaft is slightly higher than the other point. Slightly offset.

Sorry, I'm not following. Maybe a picture would help me understand. The points are always an equal distance from the crankshaft where they mount? And always the same height if they are installed correctly? I suspect we have a "failure to communicate'' when it comes to "set the points".

Also When I put the flywheel back on and torqued it, when I go to pull it over the flywheel wont move?...Didnt have that problem last time

Hmmmm, looking at the picture of your magneto on the previous page. Is that coil screw loose? The one farthest from you? Something doesn't look right about that. But it may just be the picture quality. Good luck, and keep at it!

Cheers..................Todd

 

[chiefcatchemall]

Re: 1973 Johnson seaking 20 hp

Nope I figured out what you meant! I am gonna replaced the primary charging coil. See if that fixes the problem. Will report back once its replaced! The wire leading to the top cylinder out of the primary coil was pinched and looked bad. Tried to twist and shrink wrap. Didnt do the trick. Wires probably broke off inside the rubber