Johnson TN 27 Question

[johnny]

Can someone tell me how many splines there are on a Johnson TN 27 driveshaft where it slides into the bottom of the crankshaft?

[Mumbles]

I can’t say off the top of my hat but they are multi splined. If I look around tomorrow, I should have a shaft out in the shop somewhere and could do a count.

[crosbyman]

maybe… 8

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[johnny]

I have two TN-27s that the splines in the crankshaft are rusty and are striped. I guess the only way to fix them is with replacement crankshafts that have good splines. That’s why I am asking how many splines they have. I know the TN-26 model only have 4 or 5 splines.

[Buccaneer]

Perhaps there’s a good “farmers fix”, or “crafty machinist” fix
for the crankshaft?
If so, I wouldn’t mind hearing them.
Then again, probably lots of TN-27 parts “out there”.

Prepare to be boarded!

[Mumbles]

The parts motor I have in the shop was a coarse splined TN-26. Sorry to keep you waiting.

If you have a bad shaft with good splines, the end can be cut off and grafted to a good shaft with bad splines. I’ve done this fix on quite a few motors with good results. When it warms up a bit, the ’69 Merc 200 will be the next one getting this treatment done to it. Watch for it!

And another one.

[bobw]

Mumbles – very nice machine work. Great fix.

Bob

1937 Champion D2C Deluxe Lite Twin
1954 Johnson CD-11
1955 Johnson QD-16
1957 Evinrude Fastwin 18
1958 Johnson QD-19
1958 Johnson FD-12
1959 Johnson QD-20

“Every 20 minute job is only a broken bolt away from a 3-day project.”
"Every time you remove a broken or seized bolt an angel gets his wings."

[Mumbles]

johnny wrote:

I have two TN-27s that the splines in the crankshaft are rusty and are striped.

Ahhh, it’s the crankshaft which is boogered. OK.

Here’s a JW which had the splines stripped in both the crank and on the shaft. To ‘fix’ it, I silver brazed a socket to the crank and cut and shaped the top of the driveshaft to fit. The three horse JW doesn’t develop a whole lot of torque so it should last for a while.

I picked up a four horse last year with a Macgyver fix for stripped splines in the crank so I’ll see if I can’t find some photos of it. The way it was done might be the easiest way for your TN.

Here’s the JW three horse.

[lloyd]

I can’t get to my shop to count the TN 27 splines, but I think it is 8 splines.
If you need new primer seals and instructions for your TN, as you probably will, just contact me directly at lautharr@sbcglobal.net or 231-929-7479. I tried to post an ad in the classified section, but it wouldn’t let me.
Good luck!

[crosbyman]

my picture above shows in plain view 3 splines + one on each side edge of the picture for a total of 5 PLUS

3 on the back side which we don’t see so ……

grand total must be 8

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