Johnson Seahorse TN-28

[HighTrim]

Re: Johnson Seahorse TN-28

Uh OH :facepalm:

The TN flywheels usually pop off pretty easy being only a 5hp. Hopefully some rocket scientist didnt loctite it on!

What are you using to hold the flywheel? Do you have an extension on the wrench that is on the center puller bolt? Put a pipe on the wrench and crank on it, she will pop.

 

[mindspin]

Re: Johnson Seahorse TN-28

I'm using the rope trick from the biglureslittlelures site in the lower spark plug hole. Seems to hold everything in place.

I don't have an extension yet but will dig through the shed this afternoon to see what I can come up with.

 

[sutor623]

Re: Johnson Seahorse TN-28

Man I know some guys are against it, but what I do is thread the puller in real good, then put an air compressor on it set really lightly. Since you now dont have to worry about holding the flywheel still, it should pop right off.

 

[kfa4303]

Re: Johnson Seahorse TN-28

A little rubber strap wrench, or a buddy, is helpful for holding the flywheel in place too. Reference the pic I posted earlier for the proper use of the puller. It shouldn't be too hard to get off being that it's only a little 5 hp, but you never know what might the PO may have done to it. You should be able to find appropriate springs by taking your one good one with you to the the hardware store and finding some that match the diameter and coil count. They may be longer than yours, but you can always cut them down to size and shape them as needed. Good luck.

 

[nwcove]

Re: Johnson Seahorse TN-28

Man I know some guys are against it, but what I do is thread the puller in real good, then put an air compressor on it set really lightly. Since you now dont have to worry about holding the flywheel still, it should pop right off.

i also find an impact gun....used right.... will usually get the stubborn ones off.

 

[sutor623]

Re: Johnson Seahorse TN-28

i also find an impact gun....used right.... will usually get the stubborn ones off.

Oh yeah man. You just have to make sure that the main stud is threaded all the way through the puller. I have stripped the stud out because it wasn't threaded all the way through.

 

[mindspin]

Re: Johnson Seahorse TN-28

I FINALLY got it off! No special trick or anything, I just kept pulling and this time it popped off.

Again, I'm no mechanic but here's the problem... It looks like the other coil (blue) had been replaced at some point but I'm assuming I'll replace both while I'm at it. Everything is pretty dirty and there's cobwebs underneath everything.

 

[nwcove]

Re: Johnson Seahorse TN-28

she should be running in no time!! hope my tn 26 comes apart without to much grief.

 

[1946Zephyr]

Re: Johnson Seahorse TN-28

Shoot, I would just put those coils back into service. Just fix that broken ground wire and replace the spark plug leads. Those coils generally don't fail, unless the insulation is cracked. You can probably get by with cleaning and regapping the points too.

 

[mindspin]

Re: Johnson Seahorse TN-28

I was going to see if I could find an ignition tune-up kit at napa or somewhere locally but the ground wire should be easy enough. The blue coil seems to be in great condition after further investigation but the brown one I'm not so sure of. It's not cracked so I'll replace the wire and see what happens.

 

[HighTrim]

Re: Johnson Seahorse TN-28

Yeah both those coils have already been replaced recently. They are not original. I have never seen a brown one like that though, anyone know the maker?

I would definately test them though before closing her up. This will help you with how to do that.

http://www.pochefamily.org/outboard/Coils.htm

The points and condensors have been changed as well. I would dress (file) the points, clean them with acetone, fix the ground wire and you will likely be good to go. So far so good. Next step carb or waterpump?

 

[mindspin]

Re: Johnson Seahorse TN-28

Thanks for the link, I will check the coils with a multimeter tomorrow and file the points. Is it crucial that the ground wire be an exact match or will any similar thickness wire that will ground it work?

I was going to do the carb next, is there anything special that I need to know with something this age?
I'm going to follow this http://www.pochefamily.org/outboard/CarbService.html

 

[HighTrim]

Re: Johnson Seahorse TN-28

That link is pretty thorough.

Post pics of the float and such when you get it apart. Good luck.

Before reinstalling the flywheel, be sure that the ground wire is tucked in tight to the coil like the blue one, and the wires off the condensors are pulled down tight, to ensure you dont get them cut again.

 

[1946Zephyr]

Re: Johnson Seahorse TN-28

Yea, I usually push them tight against the back of the coil, so the cam and flywheel won't hit them.

 

[mindspin]

Re: Johnson Seahorse TN-28

OK, in the picture below, if I push A in the direction indicated by the arrow then the other end (B) opens up and never closes like the other one does. I'm assuming the spring mechanism in the middle is broken somehow and not sure if its feasible to take it apart. Is there a kit for this to just replace the points and condensors or is everything separate? EDIT: Found it, SIERRA 18-5006 P 172522 J/E TUNE UP KIT

Also, the spark plug cables had been replaced at some point but the opening indicated by C is pretty corroded. I think I'm going to replace the wires and boots while I'm at it.

I'm having a small string of bad luck so far, I can't find the three small springs for the life of me for the puller and replacing the wire on the coil requires me to buy a spool everywhere I go, I just need 2 inches of similar wire to solder I'm assuming will do the trick?

Also, the blue coil is a Prufex 580-197 "Made in West Germany" to give you an idea of its age

 

[mindspin]

Re: Johnson Seahorse TN-28

OK, taking it apart and back together STILL doesn't work right. I guess the whole thing is bent some how? A $16 replacement kit is on the way.

 

[cajuncook1]

Re: Johnson Seahorse TN-28

Please look at this link. It may answer some of your questions regarding the wire, points, and coils. The diagrams in the link will identify which screws hold down what. You have supplied a picture of your magneto so you have a reference as well as the diagrams from the link. Replace one side at a time so you have reference of how the pieces go back. You will do just fine. We all started where you are now and have learned through guidance and hands on experience. If you read through the Johnson manual it explains a lot as well.

http://forums.iboats.com/showthread.php?t=531940

 

[kfa4303]

Re: Johnson Seahorse TN-28

HI mindspin. Glad you got the flywheel off. The rest is easy. For starters, part "A" should rub against the crankshaft cam which should be slightly oblong (oval shaped). As the lobe of the cam rubs against arm "A" and opens the points. Find highest point of the lobe such that it opens the points to their maximum. This is the point at which you want to set the points to .020" using a feeler gauge. The gap of the points, while in the open position, is adjusted using what looks like the flat head screw at the base of the points (circled in white). Use this to adjust the points accordingly. A .020" should just barely be able to slid in and out with a slight bit of resistance. Once the first set of points have been set spin the crankshaft clockwise 180 degrees such that the highpoint of the oblong is now on the arm of the other set of points. Repeat the gaping procedure described above and set the points to .020". The points function like castanets. When one set is all the way open due to the high point of the crankshaft cam, the other set fully closed. While you could try to repair the wire on the coil you have, I would probably just get a new one to be safe. Here's a pic of a nice pretty magneto with the point adjuster circled in white along with a handy link about setting up your magneto. I would get some fresh spark plug wires too. Be sure to get 7mm COPPER core wires (modern automotive wires will not work), and new 90 degree boots and connectors. I got my wire at Napa for a couple bucks a foot. The boots were about $5 for a pair too.

http://www.outboard-boat-motor-repa...on 3 HP 1952-1967 Ignition System Tune-up.htm

 

[mindspin]

Re: Johnson Seahorse TN-28

Thanks guys, I really appreciate all of this help and information. Hopefully I will have everything by the end of the week and it seems pretty straightforward. I'll post pictures as I go.

 

[mindspin]

Re: Johnson Seahorse TN-28

The parts came in today and everything is back in place. Note this pic was taken just for reference, I've since adjusted the wires and screws.

However, I can't figure out how to set these boots up with the coil spring. I've been browsing youtube but all the videos I've found so far are using different terminals. Can anyone explain this? Is it easier to using something else? This is what came with the kit I ordered.