One of the weak points in some of the old Cats is the steer clutches. I don't know in how many models,but experienced it with the 9u D6.Do not just let go of the steer clutch lever and let it fly forward.Would surely apply to the 3t D7 as the steer clutches are the same.


I was digging a spring for my dad lots of mud. I don't even remember why I got off the tractor but got mud all over my hands. Went back to pushing and pulled the clutch to put all power into one side. Lever slipped out of my fingers,:confused2:and had one of those moments of what happened what did I do. All the bad stories came rushing to mind. As both tracks now spinning in the muck,maybe I got away with out damage.

I don't remember how long but within just a few hours I had not power to the one side. When it was apart the short shaft in the steer clutch was sheared. The metal looked crystallized but in 1000's hours that is the only one of those shafts I had break.So I am sure the shock was the the cause of the break. So I can say that story was proved and I don't need to do it again.

I have tow started some old tractors, but more often around here they get parked on a hill and coast started. Never heard any stories of breaking axles in any of them. So as with many things don't give big jerk to thing when towing.

Just make sure you hang on when coast starting something. A guy that I would bet coast started all his tractor of all brands a 100 times for every time he used a pony or a battery fell off a TD 9 and was killed about 10 years ago.


Good deal that it ran for you. From experience and observations 30 year old diesel is better to have in the old tractors than the 5 year old junk diesel we buy today.

"d2gary" wrote:

Better be careful Nathan, 1 Cat can be justified because i have this job or that job to do with it but 2 is getting dangerously close to becoming a "COLLECTOR ".
Looks like a good score and close to home and running is a huge bonus.
Hopefully the border will open soon because now I'm wanting to come and see your projects.
My 5t was the first d4 I acquired and I have done a lot of work with it.
Keep on collecting 😆

Haha yes good points Scott. Maybe I should have considered that before I bought but I think I already had "yellow fever". Problem is my wife has been out of town with the kids for a few days and I've done this without her knowing. She might have a slight hiccup when she figures our what happened 😮 Good thing I didnt spend too much! It is almost out of sight. We only have .75ac so hard to hide things 🤣

You can only see the top of the canopy from our boot room so maybe it wont be too obvious!

"Mangoman" wrote:

Haha yes good points Scott. Maybe I should have considered that before I bought but I think I already had "yellow fever". Problem is my wife has been out of town with the kids for a few days and I've done this without her knowing. She might have a slight hiccup when she figures our what happened 😮 Good thing I didnt spend too much! It is almost out of sight. We only have .75ac so hard to hide things 🤣

Haha the old wife's out of town purchase!
When I got my first d2 for reasons I will never know I took my wife along with(that hasnt happened since) you can't believe the expletives that came out of her mouth when she saw my diamond in the rough. The "first" d4 was questioned with some enthusiasm but after 8 or 9 that have come and gone she's pretty well worn down and doesn't even comment anymore.
You just have to wear them down , besides with all those youngsters you don't want them fighting over a tractor best to have one for each! 🤣

Pulling something “off” to start it is much less strain on the driveline components than operating it.

Only gotcha I can think of is if it was hydro locked from some liquid in one of the cylinders. Pulling machine has no “feel” to detect that resistance before a connecting rod is bent.

Things are bound to break eventually, something will eventually give, but the D6b is the only tractor I’ve ever heard of breaking the bevel gear shaft on one side. They’re not too different from the U series D6 or the R’s for that matter, so I’m guessing the increased hp available from the D333 with the transmission in low gear could eventually find a weak spot somewhere.

On the other hand you hear of the hot rod AG tractors with 6-71 Detroit diesels that were created in the pacific NW USA! I think an operator had to use a little common sense to keep one going long term!

I’ve got a 6V-71 out back and some 9U’s......maybe I should make one just for fun!

I think we were at little risk of hurting anything as I had taken the cover off the fuel pump and worked it back and forth with a little penetrating oil until it was smooth. I had turned the engine off the fan blades prior, decompression at low speed with a smooth engagement of the main clutch. I have to replace a coolant pipe gasket up top, get the.pony running. Also the radiator has some really foul looking rusty sludge in there. Have to deal with that. Free up the left steering clutch. Missing one top roller. Check and/or change oils. Oh I guess I have a bit of work! So far my wife hasnt noticed it in the yard. I will just leave that be for now 😁

This weekend I went through the carb. I drilled out the solder plugs, made sure the float still floated, carefully put a torch tip cleaner into any small orfice. It's got new gas in a clean plastic tank, new fuel line, new plugs, comp tested the other day and was getting maybe just shy of 40psi on first pull and peaking out closer to 60. I cant get any signs of life. I'd like to replace the plug wires but the spark does seem good. Has new Autolite 386 plugs. I didnt check the gap but perhaps later this week. Any thoughts?

And yes my wife NOW knows about my "new" Cat. She didn't notice on her own though. I brought it up! She did get pretty excited. May have said "if you bring home another piece of junk I'm leaving!" 😬😮😁 I'd better hold off until she softens up 😂

"Mangoman" wrote:

This weekend I went through the carb. I drilled out the solder plugs, made sure the float still floated, carefully put a torch tip cleaner into any small orfice. It's got new gas in a clean plastic tank, new fuel line, new plugs, comp tested the other day and was getting maybe just shy of 40psi on first pull and peaking out closer to 60. I cant get any signs of life. I'd like to replace the plug wires but the spark does seem good. Has new Autolite 386 plugs. I didnt check the gap but perhaps later this week. Any thoughts?

And yes my wife NOW knows about my "new" Cat. She didn't notice on her own though. I brought it up! She did get pretty excited. May have said "if you bring home another piece of junk I'm leaving!" 😬😮😁 I'd better hold off until she softens up 😂

-40 psi on the first bump sounds a little weak, but i think it should fire and run...?
- can you squirt some gasoline in the carb intake or spark plug hole....should fire at least if timing is anywhere close...?
-i like autolite plugs, a gap anywhere between .020 and .030" should work fine...

Yes I didnt think 40psi was great but I comp tested my D4 7U as well and it was about the same and it started all last winter, mind you on electric. I cant get a caugh, nothing. I drizzled down the carb as well. May check the plugs later this week.

40 pounds is plenty, guys have talked about 25 pounds and running happy, sounds like a spark issue to me, if you are pouring raw fuel down the holes and not getting a poof, you have no spark where it's needed. Having a spark outside the cylinder, is no guarantee you have sparks inside the cylinder under compression, get your magneto serviced.