Look what I stumbled across

Not mine, just a came across it on the roadside. What can you tell me about it? What year? HP?

Looks like a mid 30s JTU, probably around 30 horsepower , were replaced in 37 by the ZTU

Wonder when the Twin Cities name ended and MM began? As there's some of both on this tractor makes it look like it was a phase out/in transition. I thought the UNIVERSAL name applied to the two front drive wheel/rear sulky tractor, but what do I know being more of a green, red, orange guy. Any old tractor is wonderful and interesting.

My '37 JTU says the same Twin MM City on the radiator tank.

The serial tag should be on the right hand side of the transmission case.

Thought of SN tag too late. It's now nearly 1,000 miles away.

Neat little Jay. Air cleaner in front of radiator long since lost.
Original Waukesha engine and "bag of snakes" manifold.
Bet the engine is just worn out. Bad reputation. Poor, make-do engines until the RE (R&Z) engines with side valves were ready to use.
The only NEWLY designed MM tractor to carry the Twin City name? This J is an all MM design.
The older models carried the Twin (MM) City name into at least 1938 on their cast iron rad top tanks.
The AT 20-35/27-44, the TY 12-20/17-28, the KT, MT and FT 21-32 were MS&M Twin City designs before the merger.
In 1936, the older models started to change from Twin (TC) City to Twin (MM) City on the top rad tanks. Changes coming.
Losing the Twin City name was a careful thing with MM. They didn't want to scare off regular Twin City customers.
A gradual change until the Z and Visionline Series in 37.
The new U in 38 (a new edition of the K's&M's) also helped the change from Twin City to MM.
Do I have all that about right guys?
I'm surprised the manifold looks about as bad as most manifolds around here and its worlds away in the desert versus the humidity here in MN.
See that PTO block-off cover? A KT101A. A KT part on a J... Neat.
And it says Universal on the tank rear. Cool.
All-Fuel manifold with a gas only tank...
Thanks for the very nice pics!
Sure didn't mean to give a full dissertation. Hope its OK to do so.

As I appreciate any old tractor, I really appreciate your full dissertation. Knew it was something special. It would be fun to get her running again, but leaving in
work clothes as the tin is so nice. High Wyoming desert is preserving it pretty well.

Probably one of MM/Tc biggest mistakes. The RE motor was not ready when smaller TC was needed. They stuck Wauk designed motor in
it. It failed badly and many were retrofitted with RE when it came out in 1937. All MM pto covers are same. KT/J /U/Z

Here's a couple pictures of mine. It's about as original as can be, and loose in every joint, but she runs great! I had it out last week one day and drove it around. Started on the second or third pull of the crank.

Nice tractor you have there. Does yours have that same label cast into the manifold heat exchanger? Looks to be labeled HEAT CONTROL FOR MANIFOLD
AND SEAB?? ? Wonder what those last two letters are?

Fuel and season it should read

Thanks - makes sense to me.