Farmall M head help

Caseih14

Member
I had many responses on my last topic! With the help of you guys i found out i had 2 stuck valves, pulled the head, got the valves to move, the push rods are nice and straight, my question is for cleaning... should I be doing it or should i just take it to a machine shop? Any help is again greatly appreciated!
mvphoto41288.jpg
 

Maybe you should post pics of the head if you want advice.

At this point it like you were told in the other post, DO IT RIGHT

So take the head in have it re-done.
 

You were still posting pics!!!!

The only way to tell what you have is to remove the valves and have a look.
 

It looks like the valves are deep in the head.

Take it in and have put back to spec.

That means a valve kit, new seats, etc.

They will tank it and test it too.
 

Ok, so just take the head in, or the rockers and stuff too? And still for the engine block... cleaning the carbon off that, what is best to take that off with? I know dont scratch it or anything
 
(quoted from post at 17:11:32 08/18/19)
Ok, so just take the head in, or the rockers and stuff too? And still for the engine block... cleaning the carbon off that, what is best to take that off with? I know dont scratch it or anything

You were also told to get a manual & not an IT.

There are lots of reprint manual for these on ebay, maybe this site too.

You are going to need several specification before you get this back together.

We cannot evaluate you rockers and such from here.
 

Im just saying, if i go to a machine shop tomorrow, and just bring them the head, are they gonna ask for more stuff amd im gonna look like an idiot, or is that all they need for a valve job?
 

Im 17 and havent done this before so I honestly dont know, im just asking questions in hopes of more info, cuz im guessing a service manual doesnt tell me what to clean the carbon off a piston with
 
(quoted from post at 17:27:43 08/18/19)
And whats an IT?

It is a manual brand you do not want.

Take your rockers and have the shop look at them. They may need to be surfaced but may be useable.
 
ok good its off. now get a valve spring compressor and remove all valves in order. from front to back. get a block and drill holes in it for the valve stems to sit in. they must be kept in order incase they will be installed again in the holes they came out of. you can clean the valves by soaking them in carb cleaner, or use brakleen or using a wire wheel on a grinder. just be very careful with the valve face and seat not to damage them. your doing good so far so why quit. once all clean then post a picture of the valves faces., and seats. then I will know if they are good to use or need a grinding.
 
What I would do, is to take the head to a automotive machine shop, they will know what its going to need after inspection. Then they can price fixing the head. As for cleanup, use a wire brush, etc to clean it up. Ive used Scotchbrite on some surfaces like that with good success, and cleaned up the surface with carb cleaner before reinstalling the head gasket.
 

Valve spring compressor is something i dont have, ill look around on youtube to see if there are any practical ways to remove them without one, if not what do they usually go for?
 

Then again the reinstalling part will probs not work, ill see if i can pick 1 up tomorrow, and for cleaning, I know you can get them dipped, then they are like new, but just me cleaning, how clean can i get everything/how clean should they be?
 

Everything in the block and on the head seems to suggest nothing should be warped or anything, everything turns and fits nicely, the only problem was the 2 stuck valves, and I know we are working with thousandths of an inch but it doesnt look like it ever got hot, just from 2 stuck valves would they have to do any machining because of that? Or just clean it and maybe have to replace the valves?
 
when I was 16 years old I put rings and rod brgs. in this very same engine. that was a long time ago. I have done actual valve grinding so I can give you accurate info. on whats needed to be done. doing yourself your learning and saving money.
 

And for valve spring compressors, from what i can gather there are 2 different kinds, one thats like a big c clamp which is like $100+, and then one like this for a fraction of the price

https://www.canadiantire.ca/en/pdp/oem-valve-spring-compressor-1250055p.html

Would the cheaper one's design work on my head, or should i go with the expensive one?
 

I helped rebuild my 2009 yfz 450r quad last year, although nearly 70 years newer and 3 less cylinders it looks quite a bit different
 

Compared to how it looked how do you think its coming along? That was just after a 1 good scrub to get the main stuff off, now just keep going until she's clean?
mvphoto41293.jpg
 
do as I say, you are getting too much different info here and mixing you up. just post pictures of your work and all will be good. you need one teacher not a bunch of advise from people that could not do a valve job if they had to, nor know a good reuseable valve to one that is need of replacing. or even know where the valve seat should be sitting on the valve face.
 
your doing good. get some brakleen and scotch brite pads and give it the final cleaning. blow out with air, stuff will be leaking into the ring grooves. yes clean pistons at tdc.
 
(quoted from post at 15:57:22 08/18/19)
And for valve spring compressors, from what i can gather there are 2 different kinds, one thats like a big c clamp which is like $100+, and then one like this for a fraction of the price

https://www.canadiantire.ca/en/pdp/oem-valve-spring-compressor-1250055p.html

Would the cheaper one's design work on my head, or should i go with the expensive one?
where are you located , from the link are you Canadian?
I have 2 extra big c type compressors. maybe I can help you out
 

Buuuuut, what would you recomend, the big c clamp style? Or the little overhead type that grabs the spring?
 
c type and you got it forever- maybe a local shop will loan you one or a high school
40 years ago every farm equipment dealer (just about) had valve servicing tools but most send everything out now , around here they aren't too hard to find
Theres a lot of advice in your project thread and I know you are excited and eager to learn. I think you could have freed those valves and possibility saved yourself a valve grind gasket set if the head turns out in good condition
Myself, I like to get a dead tractor running to assess the condition before I commit to it. now that its off that's not an issue so good luck as you go and have fun :!:
 

Thanks! Im enjoying doing it myself, learning and I will take more pride in it when its done, built not bought!
 

Planning on giving it another good cleaning once the engine is back together, thanks for the reminder! Also what works best to get into the smaller areas on the carb? Just those small brass brushes?
 
Externally yes. Remember a rule that rewards. DO not do more than one repair at a time if at all possible. Experienced mechanics diagnose and repair
systems alone so as not to confound the process of getting it running. So leave the carb cleaning, and other issues for the day after it runs. There
is enough on the menu at this point. Jim
 

Ya, im not starting anything else until the engine itself is back together, i have my mind on it and what needs to be done, gonna grab a spring compression clamp tomorrow after work, bring it home and start pulling the valves, then fingers crossed they're good to re use! Clean them, and start the re install
 
A rotary wire brush helps get carbon off of the head and stem. They are so hard, that the brush will not damage them at all. The guides should be
cleaned with a skinny tube brush, and carb cleaner. Reassemble with engine assembly lube. (seriously). Before taking it apart, Turn it chamber side
up, and pour ATF, into each chamber. If they stay full, they are OK as is and don't need grinding. Open valves and stuck valves may have had stuff
stuck under the seat/face seal and leak from junk, not wear or cracks. Check that if you have some that leak. Make sure to use a piece of cardboard
with 8 holes, and a good partitioned plastic tray to hold all parts in order so they go back where they were. Good luck, take pictures. Jim
 

I got a board with holes drilled, and chamber side up i already sprayed some lube in hopes it would soak, they didnt drain so i was kinda confused lol, makes sense why it didnt drain then, cuz it wasnt supposed to :D watching a lot of youtube, seeing different peoples takes on it and how they do it, thanks again everyone for the advice! And hopefully tomorrow evening im able to start the re assembly process, at least get everything out and cleaned
 
(reply to post at 19:27:18 08/18/19)
And a tube brush? Like a literal brush? With softer bristles? Or more of a brass or bronze type brush with stiffer bristles like for cleaning guns?
 
jim ,that is not so, just because a valve chamber is staying full don't mean the seat and valve is good. you need a visual inspection. each seat requires a width. not the width of the valve face if its like that then a valve job is in order because the seat is pounded out and the valve face will have a ridge in it. the seat width must be positioned in the middle of the valve face. but yes it will run like that but that don't mean the valves are up to snuff. I am talking about a proper valve job. this guy wants to learn proper job so why give him not proper advise. have you been taught and done a proper valve job yourself?
 

Just cuz its holding fluid doesnt mean im not gonna take it out, i still wanna get em nice and clean, then ill post pics for yall to see and get your opinions if they need to be replaced or it they will work as is, im this far im not quittin now, gonna take it all out, and put it back nice and clean!
 

But i will need a brush, so stiff bristles, bronze like a gun cleaning set, or soft like a paint brushes bristles?
 
don't get to carried away watching u tube video's . I watched some and they are beginners showing their stupidness. that is one place I don't have much patience for. they are not even mechanic's. just wanna be's. there is a lot of garbage that gets posted on that u tube. AND the important info like spec's is not given by most of them.
 

True, but i still need a visual base, descriptions is one thing but an actual video where i can watch at least how to remove the spring clips, stuff like that is good, but sorry to sound repetitive, but type of brush?
 
Rusted has it. You can clean it up your self or you can pay them to do it. As for the valves yup they look to set a bit low in the seats. And after 75 years they may have even been lapped in once since new. I have had engines I didn't want to spend a lot on and just lapped them in, to make them seal or get by to get rid of it along the way.
 
get a brush with fairly stiff one. I will look like a miniature baby bottle brush. and yes valves need to come out to clean them. and once clean then you check the valve guide clearance. with junk and rust in there you wont get a proper reading. if over .003 clearance would be looking to replace guides. they could be knurled but replacing is best.
 

Ok, after work once i get em out and cleaned ill post some pics, i have a caliper so just tell me what to measure
 
Really nothing to measure. Looking at each valve face (where it touches the seat) the contact spot should be 1/2 to 1/4 away from the outer edge (margin). If
you can wiggle the valve in the clean guide (dry) more than a fingernail thickness at the head, the guides, or both valve and guide, need to be replaced. A
manual is in your future because terminology and pictures are needed. If any valve does not meet these ideas, the head needs to be done at a shop. I (we)
appreciate your intent to do as much as possible, but that is the limit. Jim
 
You can get gun cleaning kits fairly cheap that have several sizes of wire brushes in them that work great for cleaning valve guides, I think pistol cleaning kit is what I got .
 
Ya , well so was I , so if your the mechanic go ahead. I have yet to see or hear of filling the chambers with oil when u pull a head off an engine. For some reason compression checking is sure a lacking thing here. And it takes visual inspections before a judgement call. My posts are actual hands on work not stuff pulled out of the rafters as many do here. I always want to see people get correct proper advise. Especially someone starting out and will be a top notch mechanic. Mechanic ?s now a days just change parts. I worked in a G M dealers ship and did valve jobs. But now it?s if a question is asked you can look on internet and find the answer also , but it don?t mean it?s correct. Very few people in modern world fix stuff nowadays.
 
Looking at the actual valve, the face is to wide and the edge looks to sharp for reuse. Wire wheel to get the carbon off the valves both stems faces and seats. If the seats look as wide as the valve faces I would change the seats and valves . As Jim said if the valves wiggle in the guides they need changed too. Any reputable shop can guide you better then we can since we can't actually check them personally.
 

And when the valve is in the guide it virtually cant wiggle, like a hair bigger and it probably wouldnt even fit
 
from looking at ur photo's , yes the seats are to wide. the valves themselves look good yet for a grinding. plus depends on when grinding how much material is taken off so you have the margin left. as a general rule the intakes seats should be 1/16, and exhaust 3/32. due to it running hotter . show some pictures of the valve seats. I have seen way worst looking seats than what those valves show.
 
about.0015- .002 is good for the valve guides. too tight and the valve will stick once hot. too loose and you will pound out the seat from the valve walking around. the valve should fall nicely into the guide. plus its a feel thing for the experienced guys.
 
yes, too wide. but that is how the guy did the job. it is not widened from wear. its a beginners valve grind.
 
its like this... the tractor will run with those valves once cleaned up and checked for leaks. OR you can take the head to a machine shop and he will soak it and do the job properly for you. your call. depends what you have planned for the tractor. I am sure you will not be running it to the pin on the governor working day in and out. other option have the machine shop hot tank it and it will come out spotless then you can assemble it. don't worry there is a lot of junk out there running that has only been freed up without a cleaning and in worst shape I am sure of that.
 

I was thinking that too, its a 1946 tractor, not a brand new top fuel dragster! It will most likely be a harrow/auger mover, not running an auger, just moving it around the yard, just a neat old tractor that i can drive as a hobby, i got the valves cleaner from my previous pics, tomorrow ill work on the head, see what i can get done, ask around, and go from there, again, the help here has been awesome! Heck, i was just gonna free up my 2 valves and try that, everything im doing right now has to be an improvement, and now i know what im doing thanks to the people on here! Besides, if im not happy with how it runs, i can always take it back apart, give me something to do lol, who knows, maybe i wont just stop at the head next time
 

I just graduated high school this year, recently got a job at a welding shop, so now im starting to get the funds to keep fixing it now, which is why after a year of sitting since we bought it, im finally getting back into it, i still need all 4 tires, and 1 rear rim, then eventually paint, decals, stuff like that, im sure it will come apart not long from now, but for now, before i throw a bunch of money at it, i want to make sure the basics are there, runs and drives. Once those 2 are checked off, ill hopefully get it i to a full on restoration!
 
a shop will not reuse these 2 valves. they have rust pitting on the stem. plus the bottom one is junk, no margin left, as it been ground too much.
 

It will most likely be years from now, but thats the end goal, and then tbh, get a tractor collection going!
 
Kid! If you put anymore into this post, you're going to need a publisher to put it to a book! Lol! It's been a while since I've seen such a long
thread. Good! It means you're on top of it. Very happy to see you taking this project on instead of farming it out. I've done a few "shade-tree"
overhauls, all with good results. There's about 150hrs on my H since overhauling it about 12 years ago. The only thing I would have done differently,
is break it in on the dyno instead of road gear & lots of hills.

Good luck in your adventure!
Mike
 
(quoted from post at 09:34:20 08/20/19)

Haha, thanks! I hope it turns out! Cool looking tractor and I cant wait to finally drive one, and im sure if i run into any issues ill be sure to stop here first, the help has been tremendous! Dont know where id be without it, probably still poking the valve springs with a screwdriver lol, definently a cool hobby and glad i came to pick it up! Awesome community and cool machines! Again, thanks for all the help everyone!
 

Dont worry, there are a lot of em out there who still know nothing about hands on work, I was lucky enough to be born into a farming family and community! One more thing tho, u see how on the right the water ports are open, and they left they arent, they should be open too right? And how some of them are triangle shaped but only have a small hole in them, they should be completely open as well right?
mvphoto41448.jpg
 
All passages are to be open to cast iron. There are no reasons for rusty material to be left as is. Clean them. Also clean, by
running a wire through it, the oil passage to the valve gear. Jim
 

I believe so, that makes sense as i dont know how they would close right up, while all the other ones are open
 
Oops! Forgot to mention, the triangular ports have the bottom part of the spark plug holes running under them. So, there isn't much to clean out but
the ports themselves. Off in the future, when it's all back together & running, run vinegar in your cooling system. Should clean out a fair amount of
crud. Change the water x2 & add your coolant.

Mike
 

Thanks for the tip! Will do! Just got home and started leaning the chambers, got some more cleaning supplies, brushes etc so i should be good to go today
 

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