Z129 Rebuild

So a guy gave me an at least slightly busted TO-30. I have pulled the head...not too worried about cash, but this is my first rebuild. I am thinking all the labor to get where I am...might as well rebuild the engine. Planning to call local shops that can do the mill work and install sleeves, pistons and button it all up for me...my question is...while the engine is off and out of the way...is there anything particular that
I should for sure take care of before putting the engine back onto the tractor? While my time and money is not endless, I fe
Much better about doing the work ONCE. It pains me to button something up and find out a $300 clutch replacement was in order. I guess I value my time and want the pride of knowing this tractor is sorted out. No matter if I sink $3k into a $2k tractor.
My 12 year old is helping and learning so it is a bit of an educational project.

Welcome to the group of guys who know too well that old tractors can eat more $$$$ than they are worth. Many of us are feeding the same dragon.

My brother has a Massey 202 with the Z 129. As they are a wet sleeve engine, they do not have a great deal of casting holding the 2 sides of the block together. Many of those engines have split at the center main of the block and the 2 sides of the block now bow outward. This results in the antifreeze gushing down into the oil pan. There is a shop somewhere in Missouri which will furnace braze the engine block back together, but due to the great heat, the block must then be line bored to get the 3 main crank bearings lined up with each other. So your block should be carefully inspected for this possible damage, and if you decide to go ahead with this repair, then it should be done before any engine machining is performed. Maybe you got lucky and found an engine which has not had that failure, but I am told that there are more Fergies than engines, so this is pretty common.

Best of Luck with your project!

Paul in MN

Thanks! The old man that gave it to me said I was mowing...and turned into some high grass...it started bucking and lugging and died. I could not get it started again. 15 years later, I have it, was trying to run a compression test and the radiator front cylinder would not turn over under pressure (like an exhaust valve stuck). Anyway, I dont think the block is busted, but who really knows.... I pulled the head and along the way found a sloppy front crankshaft bearing:seal. thanks for the tips!

Those are really simple engines to rebuild.

The cracked blocks are freeze cracked, not really something to blame on bad design, but it is worth looking into.

The crankshaft thrust bearings were troublesome, but repairable.

The pistons/rings/liners are replaced as assemblies. The liners simply sit in the block.

Disassemble the oil pump and inspect it carefully. They are minimally built an have reputation for the drive pin failing.

Look the governor over carefully for cracks in the cage, known for failing and dropping pieces of metal in the cam gear. Best replace if in the budget.

Where the machine shop comes in is having the head worked, the crank checked, turned, polished, whatever it needs, the rods checked and new bushings fit to the new pins.

With a shop manual in hand, you doing the basic work, letting the machine shop only do the necessary work, this is a doable job. Having a drop in ready engine is going to greatly increase the cost! A lot depends on where you live, and how wiling the shops are to even help with it. More rural areas are more willing to help. I live in the DFW area, and can't name a single reputable shop that will even look at an antique tractor engine!

Back to your original question, things to do while it's apart, visually inspect the clutch, pressure plate, flywheel surface. If any doubt, replace the clutch assembly.

Look at the starter gear on the flywheel. It will be worn in 2 places 180* apart. It doesn't need to be perfect but if any teeth are worn more than 1/4 gone best replace it. On the early engines, the gear pressed on from the back side of the flywheel. If converted to 12v, the starter will try to hammer the gear back. While you are in there, tack the gear in place, especially if converting to 12v.

And replace the transmission input shaft seal. Easy and you're right there.

Take a look at the front axle, the pivot pin and bushing, Chances are it is beyond worn. If the bushing is worn through, beyond the bushing into the bore, it will need to be sleeved and restored to the original size.

Have you checked the transmission cases for water? Very common for it to collect water, it gets in around the shifter boot and condensation. That can be dealt with any time, but if it's full of emulsified oil and water, it will take days to drip out. Don't be tempted to take the square cover off the bottom, that is not a cover, it's the hydraulic pump.

The electrical. Unless it's already been replaced, be prepared to either patch it up, or replace it all. You'll need to decide if you are keeping the generator and 6v system, or going to an alternator and 12v.

The gas tank. It's off, if it is original, unless it has had meticulous care, it's a rust bucket! A rust flaking tank will be a constant source of flooding problems!

Steering gear. Chances are it is dry, full of water, or leaking. Now would be a good time to open it up, clean it out, replace the seals, and pump it full of grade 00 grease. It won't hold gear oil for long.

Let us know how it goes...

Hello lux welcome to YT! I wondered if you would maybe be misunderstood by the terminology you used it almost seems like you may not be from the US. Please let us know so we can guide ourselves around the different explanations you might give. I am more of a Farmall and International guy but like to throw a hat in to say hello when new folks come on board.

Be aware after market parts come from the land of almost right and sometimes almost fit/perform. Think seriously about having components rebuilt versus replaced and head off future issues regardless if it costs a little more.

Replace the clutch release bearing.

I had mine rebuilt. Rebuild was great, but twice I had to replace bent or broken push rods after. Not a bad job, but took up my time. Anyway, tell machine shop to inspect the rods carefully before reassembling...save you some hassle hopefully.

I am in the DFW area as well. I will look for an engine shop today. Your insight is very helpful and straight to the point. Thanks so much.

I can tell you one not to use, Forbes in Ft Worth.

Like walking into the Deliverance movie! Avoid!!!

Seems the good machine shops are where the circle track racers go, but they stay so booked up with the regulars they want nothing to do with the walk in's.

If you find a good one, let us know!

Block is cracked in 3 places between each cylinder...so to the grave yard this tractor goes....

Texas man here. Not a foreigner at all. But I did live abroad for a couple years as an adult.

I think I am going se d it to Iowa. Midwest Cylinder Head. They can do the furnace braze block repair I read about on this forum. I am curious if anyone has ever done the tension rod repair in combination with the brazing. Seems like that would make it stronger.