M engine rebuild, where to start

This is my first go at this. I had a rod knocking, bad, checked it out and the crank has to be reground. The engine needs to come out to do this and the flywheel, clutch and all have to be torn down. So, while I'm in that deep, seems like to me I should just re-sleeve, piston, ring, crank bearings, head, valves and go the whole nine yards.

[b:57bd83c701]Problem is that I'm not sure where to start. If you guys could give some input on a logical progression of tear down it would be much appreciated. [/b:57bd83c701]

I don't know whether to just start taking things apart......or get all the parts first......or what....I'm at a loss here. Never cracked a tractor open and went this deep before. I want to do it completely myself, except for the machining............and have no experience or good friends that have a hankering to restore old tractors. I purchased the case/IH serviceman's guide from the local dealership and it is definately not a guide for a complete rebuild. It does not contain any real detailed information (an it cost me $50...bad decision) Your thoughts are much appreciated.

That's a big question!

You say no experience. Is that with motors and machinery in general, or just with tractors? That'll make a difference in the advice. No experience at all suggests limited tools and equipment. All very do-able, but you'll need some stuff.

As for manuals, either the IH Blue Ribbon Service Manual and/or the I&T IH-8 manual will be what you need. If this is your only tractor, start with the former.

Short version, the biggest challenge may be just getting the tractor split so you can get the motor off. This will require an engine hoist or a chain fall, jacks and wood blocking. There are splitting stands to be bought for this purpose, or you can make your own. The general approach is that you start dismantling the tractor from the front, and you need to have adequate,sturdy support to keep the rest of it from falling to the floor and breaking parts and bones.

General order of work? Before you do anything, check the compression on all four cylinders to get a sense of whether or not you'll need to address pistons, rings, sleeves . . . Take the head off first and get it to a shop for a good going over. Then, once the motor is off, remove the clutch and flywheel, and get the crank off to a shop for turning and cleaning. (Have the shop that turns the crank supply the new bearings.) At that point, you'll have a choice to make about how much you want to do yourself. You can pull the pistons and sleeves and redo them with new or leave them and have your machine shop evaluate them. (This is where the compression readings will come in handy.) Where you've had that knock going, I'd suggest that the crankcase go to the shop in any event, if only for a good hot tanking to get out any bearing filings. Take it to the same shop that has your head, and they can plane either or both if necessary to address any warping while they have them.

With the knocking, it might also be advisable to have a shop check out the wrist pins on your rods for wear, as well.

Best advice is not to be intimidated by it. There was a lot of engineering went into the design ofthese old tractors, but most of the work on them is a matter of assembly and disassembly, and most of that can be done with a good set of hand and socket wrenches, adjusting, fitting and checking as you go. (You'll note the absence of Phillips head screws!) And all the assembly you can certainly do yourself. A machine shop may be a good idea , if you haven't the experience or tools, to measure and evaluate things like the condition/fit of cam and the pistons, sleeves and rings.

This doesn't BEGIN to cover everything, but if you go through the motor methodically, it can make for a rewarding and worthwhile project.

Like the man said this is a big question. Be methodical and dont be intimidated. You will probably find as you go along that certain things will only come apart in one sensible order anyway, So "strip in sequence and lay all the parts out in the same sequence" because they will go back together easier that way. Remember most of these old ladies were assembled by semi skilled labour and when they got stuck they asked a skilled man what to do. You will have to read a manual in place of that skilled man. If it looks wrong it probably is and may I suggest that that is the point to ask on here what to do next. Someone will tell you in very short time. MTF

For starters, your going to have to remove the front end, and split the tractor. If you dont have what you need to do the job, and do it safely, then youll probably come out better in the long run to sell the tractor you have now, and find you a decent running M. So when you can answer the questions below, we can give you a little more advice.

You need to get a good shop manual that covers your tractor and engine. That tractor is very heavy and needs to be well supported for safety.
Spilling stands, cranes and a good set of tools are needed. You should find someone that has worked on tractors and heavy machinery to help you. You need to take pictures during the disassembly, make a lot of notes and sketches. If you don't feel up to it you may be better off to sell it and buy a good running tractor. Hal

Here's another copy of that procedure for engine removal and this is the first page. Hal

Welcome to the Club. I purchased a M 2 1/2 years ago and had no mechanical experience. By not being bashful and reading this forum daily I am now driving a completly rebuilt 1939 M. I had boxes, plastic containers from food items etc that I labeled as I put items removed into. I also laid them out on the table, floor in the order they came off. I was able to get every part needed through this site or others. If you have any questions E-mail me at [email protected]. Again, use this forum, these guys are great. Harley

Just make sure the main bearing caps are marked so you can't get them on wrong 6 months or a year later. Also keep the same caps and rods together. Take notes as you go, like the rod #s go to the cam side ETC.

If your anything like me = some days I can't remember what I had for breakfast. Take a lot of pictures as you take things apart (notes are good too". I would wait for info from the machine shop to order parts. Also clean everything as you take it apart. Good luck Jim

Excellent point. Somebody in a post down below mentioned pictures which can be helpful, too.

Something I always do is bag up and LABEL!! small parts. I use brown paper candy and lunch bags, but Zip-Locs work good, too. Then I can wind up with all my head nuts in one bag, the nuts and washers for the manifold in another with the bolts and/or nuts to mount the carb to the manifold in another. In the same line as your suggestion on keeping the rods and caps straight, I apply that to main caps, lockplates and nuts, as well, each set getting their own candy bag, LABELED!! for their position, and the lot of them going into a larger lunch bag to keep them together. For things that look alike but come out in order, like push rods, I label them individually for where they were before they go in the bag.

It may be overkill and a little obsessive (potty filter wouldn't let me use the ana- word!), but there's an AWFUL lot of 3/8" and 5/16" bolts on one of them things and it sure helps when putting things back together to have the right bolts of the right length and any nuts to go with them when you go bolting things like oil pumps, distributors, governor, . . . back onto a motor.

Should be splitting stands. Some of the men have made their own that post on here. They're very helpful. Hal

Looks like ScottHomey also address it, but your best tools are storage containers and a digital camera [you can have three books, and still have some part that you're not sure if was on "upside down" previously for a reason, or you just tried to reassemble it wrong].

For containers, I like those 30+/- oz [and a couple smaller ones] plastic coffee cans; also any pans you can steal from the kitchen, and convince your wife you're doing her a favor, make good rinse pans even if you have a parts washer.

The more parts you take in to get "boiled out" the easier assembly will be, even then you'll likely have plenty of small parts you'll be wirebrushing to remove grease caked gravel and crud.

There are a few tools that can be a considerable investment unless you can borrow them or make your own: Sleeve puller, a gear puller set, torque wrench, etc. Just check your manuals and perhaps search some threads here to make sure you don't get it half apart and "need" a tool you weren't suspecting. For a running tractor, less worries, but you never know if you need screw extractors, tap n dies ect. either.

At least you don't have to worry about it conking out in mid air.

Good suggestions so far. Line up your machine shops and price the parts and make sure you can afford the adventure before you start.

One thing though, I would hold off on taking the head in for machining until you take the crankshaft and camshaft along with having the journals miked and getting the block checked for cracks. Hate to see you get the valves ground, etc and then learn your crank is bad or there is a crack somewhere.

It's probably due for an overhaul or close to it so sleeves, pistons, rings, etc just makes economic sense because of the work to tear one down again. Then you are good for another 50 years.

Get you a gallon of carb type cleaner with the strainer in it. When you have a group of parts/bolts going into one container you can clean them at the same time for a day.

I've used the sort parts on certain spots on the floor method but invariably the piles will get kicked over and intermixed. Keep pen and paper handy. When the water pump or something has different lenght bolts, make a drawing of bolt pattern and mark where the long and short ones go.

Hard to take pictures with greasy hands but ask the wife to come out and do it every so often. Better yet use a video camera and describe what you did or are doing. I can think of countless times where I pulled something apart thinking I will put it back together shortly and don't write down how I did it, then invariably there is some delay and memory slippage and then I can't remember how it went back together.

One question I have for everyone is how to mark parts and settings, line up marks, which side faces out or in, which way the pistons point, the way the rods go on, etc? I've used welder's markers, sharpies, paint, and then the marks get washed off when I clean the parts.

(quoted from post at 11:53:33 03/19/09)
One question I have for everyone is how to mark parts and settings, line up marks, which side faces out or in, which way the pistons point, the way the rods go on, etc? I've used welder's markers, sharpies, paint, and then the marks get washed off when I clean the parts.

Click to expand...

I still do that with a sharpie! Mark something, sure I'll note the direction while cleaning and remark; then lose the locations or forget to remark.

If there is room for a chisle mark to align the two parts, or a non-critical sureface for a punch mark etc, that works; however, you still need a picture after the mark or you forget whether the punch mark goes in or out etc. :lol:

Just remember the most expensive words in any rebuild, repair or restoration " While I"m here ....."
Slow and methodical will triumph every time.
Make sure you block and hold the back half securly.

Joe

I have lots of pics on H teardowns on my website, wil give you an idea of wht you will get into.


The Farmall H

Randy

One of the most overlooked items in a rebuild, in my opinion, is making sure you have a real good tap and die set. I always would chase the threads on engines I would re do and just that little step can save a LOT of grief and aggravation. A guy by the name of Elmer Schoch taught me that and I"m sure that just that one little step saved me time and money.
Head bolts especially and their holes are trouble makers looking to throw curve balls your way.
He also taught me that you can"t have the parts too clean.
Take the little bit of extra time and trouble and the engine will thank you later by not leaking everywhere.

I didn't read all the posts, I think I would find another crank with no grinding, to much cost. You can still say original motor.

Thanks so much for the input gentlemen. I'm looking forward to getting started on my project!

Be sure to separate the parts as you remove them. I use cardboard boxes and mark each box what it contains and where it was removed. Even when you clean the parts return them to the same box. I rented an engine hoist from a local rental store and it came knockdown on a pallet and you assembled at your site. They showed how it went together. It was a heavy duty hoist and it would lift that tractor's engine easily. I think it was rated at 2 tons. It had wide casters to provide good stability with the engine raised. Good Luck, Hal