rebuilding a Cub engine -- that somebody else tore down!

[rjf7r]

I share a 1950-or-so IH Farmall Cub with a number of other owners, one of whose spouse, now estranged, seized the engine, tore it down, bought parts, replaced the valves and tappets, and then left (well, actually it's more complicated, but he's unavailable for consultation). My job is to put it back together in running condition!

I'm very handy with mechanical things and in particular power equipment, but I've never rebuilt a multi-cylinder engine.

I took some photos of the engine -- http://pg.photos.yahoo.com/ph/rjf7r/alb ... GBiu5Lue8j

I'm quite confident that I can figure out how all the parts go together but I suspect that there are some more "finer points" of engine assembly. In particular I'm concerned about desirable or even necessary cleaning, honing, measuring of clearances, bolt torques, etc. Note, I don't even have a parts illustration of this engine! Does it matter if the pistons and piston rods go back in the original positions? (They seem to be labeled with duct tape, but I can't read any numbers or letters on them!)

All advice welcome, especially if it helps me to make progress!

Thanks,
Bob

[Bigdog]

Bob - welcome aboard! You'll want to check out the service manuals at this link:
http://www.cleancomputes.com/Cub/Blue%2 ... index.html

They should answer anything you encounter.

The GSS 1007 engine service manual and the engine section of the GSS 1411 service manual should be of particular interest to you.

[Bob Underwood]

Just my .02 but by the looks of the cylinder walls and the crankshaft journals you need to take the block to a rebuild shop and have them take a look and give you an opinion on what needs done. If it were mine I would not reassemble as is.

Bob

[trac48]

Hi! I believe we are in a similar situation,

I just bought a cub with a broken block, so I have to refurnish the new
block with the old parts, so yes it would be better to put the pistons in
the proper place so they will sit on the same place on the crank- shaft,
so that the wear of the bearings would match the wear of the crank.

so far so good, you're lucky you don't have to play with gears alignement or cam,But I would suggest you try to get a motor rebuilt book.
I am sure somebody more knowledgeable will come along on this site and help you some more.
Meanwhile good luck Gilles

[Jim Becker]

Does it matter if the pistons and piston rods go back in the original positions? (They seem to be labeled with duct tape, but I can't read any numbers or letters on them!)

Each connecting rod and connecting rod cap should be stamped with a number 1 through 4 to indicate position (from the radiator end) and orientation (number towards the camshaft). The matching up of numbers and orientation should be carefully followed.

It is late '55.

[Jim Roy]

Bob
Welcome to the greatest form on the web. You came to the right place there is a wealth of info. here just follow BigDog, Jim and the other guys sugestions and they will lead you in the right direction.

Jim

[Eugene]

Welcome.

You are a long ways from putting the engine back together. At this point the engine needs to be completely disassembled, cleaned (boiled out), measured - options discussed.

So, some opinions - strictly mine.

If you have small engine major overhaul tools, micrometers and a fair amount of experience with engines. Go for it.

If you do not have the necessary tools - large engine bore tools are to big - it will probably be cheaper to have someone else rebuild the engine or to purchase a complete running engine from one of the advertisers on the board.

Options:

Try to rebuild the engine yourself.
Purchase a short or long block - some where around $1200-
Purchase a used engine.
Have a local mechanic check out the engine. Provide you with some options.

Eugene

[Rudi]

Bob:

First, to the greatest forum on the internet, and to the Cub Family. You will find that all the folks on this forum are kind, helpful and just full of Cub info and knowledge. They also happen to be the finest folks I have ever met


Basically all of the technical infor you will need can be found in the links below.. all available on the Cub Manual Server. It would be a good idea to get honest to goodness ones from Binder. The CaseIH manuals are just ok, the reprint quality is not what it should be.. unfortunately.. (sorry Larry )...

Just have some fun, take your time and ask all the questions you want. Remember only the question NOT asked, is the dumb one...

Ok, so here is the spiel :

I would suggest that you read this thread: New Members and Visitors, Please READ Prior to Posting. There are many great links to informative pages such as the ATIS FAQ's 1 and ATIS FAQ's 2, The Best of H.L. Chauvin who has written very interesting articles on troubleshooting common problems with your Cub. One of the other projects we have been working on and it will be a continuing effort is the How To Work on Your Cub - Maintenance Tips and Techniques. This the the place to go to get all the quick links to some very good articles written by many members of the forum on solving some of the problems we encounter as we repair, maintain and up-grade our Cubs. Keep looking for this to grow.


Also, you might want to visit the Cub Manual Server as there is tons of info on servicing, maintaining and re-building your Cub. In addition to this basic information, there are also a number of other useful tools available on the server. There is the Specialty Services page which has contact info for neat stuff like getting your seats recovered, buying quality Decals, Serial Number tags and a host of other neat items. Also there are the Parts Pages - both Used Parts Suppliers and New Parts Suppliers pages with links to quality dealers. I am always looking for YOUR favourite dealers for New and Used Parts to include here. These pages are intended to complement our Official FarmallCub.com Website Sponsors:

JP Tractor Salvage
Ralph's Cubs
TM Tractor Parts

I would also recommend that you visit Binder Books and purchase the three most important manuals you can own for Maintenance, Repair and Rebuilding your Cub. These are the Owner's Manual, the GSS-1411 Service Manual and the TC-37F Parts Manual. Although they are available on the Cub Manual Server, it is better if you also have your own paper copy. Binder Books is the only Authorized IH Publication Reprint House and they have the best quality manuals available. Most other's are not of the same quality. Just a personal thought here, the I&T Shop Manuals, although helpful in some areas, really are not sufficient for the job. If you wish though, they are good additional reference works.

IF you really want to get the skinny on all things Cub, might I suggest you get a copy of Ken Updike's Farmall Cub and Cub Cadet's . While you are at it Original Farmall Cub and Cub Cadet is Ken's latest addition to the series. Along with Guy Fay's Letter Series Originality Guide, these are three must have's in anyone's collection.

In addition to the above information, don't forget to check out the various articles that are available to help with your Repair, Restore, Rebuild or just your Maintenance Projects. There are a number of sub pages such as Electrolysis or Rust Zapper's, Maintenance Tips, Jigs and Techniques, Implement and Part Sketches and of course the Paint, Decals & Other Finish Questions which has the Paint Chart and the Paint Committee Decisions links.

Oh, and while the program still lasts.. you might want to check the Announcement: Navistar Free Gas Cap Offer - On-Line Form thread at the top of the Cub Forum and send away for the new style safety cap before that program runs out as well.

I truly hope that you enjoy your Cub and that you will be a frequent contributor to the forum. Again, to the Cub Family

[rjf7r]

Thanks! I'll have plenty to read and think about for a while.

Bob

P.S. I don't feel like I've just joined the "Cub family" since I have been using and maintaining this tractor for about 50 years. But I do feel very welcome in this forum!

[deputy jailer]

Bob

Welcome and good luck with the engine rebuilt

[rjf7r]

What's a ridge reamer? How important is it to ream the ridge when removing pistons?

Thanks,
Bob

[Eugene]

What's a ridge reamer? How important is it to ream the ridge when removing pistons?

A ridge reamer is a mechanical device used to remove (ream -cut) the ridge formed at the top of the cylinder due to wear.

1) The ridge needs to be removed prior to pulling the pistons. Forcing the pistons past the ridge has a tendency to break the lands on the piston.

2) The ridge needs to be removed so that newly installed rings do not hit the ridge when the engine is running for the same reason.

If you are going to buy or rent a ridge reamer - the reamer must fit in a 2 5/8" bore.

In your photos, the pistons have been removed from the block. You may or may not need a ridge reamer. I would make a pass through the bore with a medium hone then check for a ridge at the top of each cylinder. If you can feel a ridge with your finger nail it must be removed.

In you initial post you stated that the engine had been seized. You will need to disassemble the entire engine and check each individual part. The usual cause of engine seizure is a lack of lubrication. You need to find the cause of the seizure and check for damaged parts - usually bearing journals. - Including the cam journals and oil pump.

Eugene

[rjf7r]

It's clear that at least one point of damage in this engine is the front connecting rod bearing and journal. See photos at http://pg.photos.yahoo.com/ph/rjf7r/detail?.dir=8fc3re2&.dnm=b223re2.jpg&.src=ph
and following. The bearings are easily replaced, but I suspect that the previous one who worked on this engine may have filed and used a very fine grit paper to remove any high points (the pits obviously remain).

I started to remove the piston pin from that piston, but it moved out easily only one-third of the way. Then I remembered that heating the piston in boiling water was supposed to free it up, but that didn't work. I may have heated the pin too much in the process.

Bob

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[rjf7r]

Yahoo photos is closing down, so all my engine photos are now on flickr at http://www.flickr.com/photos/rjf7r/sets ... 437594599/

My remaining big decision before reassembling the engine is to hone or not to hone the cylinders. They don't look bad, but I understand that one of the reasons for cylinder honing is to wear-in the rings properly.

On the other hand, I'd rather not hone, because I then have to worry about cleaning out any metal removed by the honing (and keeping it off the crankcase bearings and journals that is underneath the cylinders I will be honing).

(I realize that almost everything I'm proposing is "AMA" -- against mechanics advice. The problem is that I'm just never going to do this job if I had to totally tear down the engine.)

Thanks,
Bob

[John68]

Bob,

I'll try not to be too long winded on this, and as a technician who has worked for both Ford/Lincoln/Mercury and Ford NewHolland and is also a farmer with not a lot of money to toss at equipment repairs; I'll give you some advice.

For starters, you mention that there might have been some journal damage on a rod journal. That is not something that should be taken lightly if you want any kind of longevity out of the rebuilt engine. Journals must be polished smooth and have extremely crisp measurements in order to ensure proper bearing fit and longevity. Even some light scratches can be damaging. Think of it as a a piece of sandpaper. how long would it take you to sand a groove into the crank if you had a piece of 1500 grit sandpaper? Now, imagine you were to spin tha tsandpaper around the crank at 1800 rpms for 10 hours. I bet that sandpaper would make quite a dent in the rod journal.
Without taking the crank to a machine shop to have it reground, you are left with very few options. The best thing to do is get some very fine 1000 grit, 1500 grit and 2000 grit sandpaper and some air tool oil. gently sand down anything you can feel with your fingers with progressive grits of paper. This is by no means a "proper" fix for the situation, but if you don't do something solid to address the journal issue, it will be a waste of time and gaskets and bearings to have gone ahead with the rebuild. It might take a few hours, but it is time well spent.

I couldn't see the damage in the pictures, but then again, inspecting something 6 inches from your face and over the internet are 2 different things. Also, I am not the most computer savy person int eh world. I could be missing something.

Now, as far as honing goes...

I am assuming you are installing new piston rings, since you have them apart? That is something that should not be overlooked. Rent some tools to do the job. You can rent tools for free from Advance Auto parts and lots of other auto part stores. Rent a piston ring expander for installing the rings, a ring groove cleaner, and a ring compression sleeve for installing the pistons in the block. make sure you clean the ring grooves very well, and wrk them with a brass bristle brush to keep the rings from sticking in the grooves. If a ring sticks, it will probably have bad compression and smoke.

back to honing...

Yes, you must hone the cylinder walls. You can rent the tool for nothing, and it is vital to teh success of the job. Keep the stones wet with a steady stream of diesel fuel, kerosene, or air tool oil. this will also help to flush away anything you remove from the cylinder walls. The proper method for honing is to run a slow rpm on a drill, and move the hone up and down in teh bore at a medium pace. Probably teh easiest way to explain it is, count 1 thousand 1, 1 thousand 2, and for every count, you should move completely up and down the cylinder bore. Down on 1 thou, up on -sand 1. Maybe slightly quicker depending on your rpm. 200-400 rpm is plenty of speed. what you are trying to acheive is a random "cross-hatching" pattern in the cylinder bore.

There shouldn't be anything more than a dull gray liquid, as far as honing debris. you could easily tie a shop rag around the rod journal before honing each cylinder. It is also a good idea to move teh crank to the pistons lowest point in teh stroke before honing that particular cylinder, to keep it out of the way. You dont want to knick the journal with the tip of a honing stone.

Another handy tool to have, is an air die grinder, and some scotch bright purple "rol-loc" disks to clean up all the machined gasket surfaces. Buy a few cans of brake wash to give everything a good "hose down" before you start installing pistons, and make sure you cover up the studs on teh connecting rod before you whack the pistons donw into the bore. You don't want to scratch the cylinder wall or a rod journal with bolt threads. Get a good clean canning jar big enough to dip the piston in, and fill it half full of new motor oil. dip the piston in the oil before knocking it in the block. Cleanliness and lubrication are nessessary to have a tight running engine.

I could go on and on, but let me know where you are. You don't want to skimp on teh cheap stuff and time, if you aren't paying yourself to do the labor, your time spent to do it right can equal big dollars for a professional rebuild.

These are just suggestions and guidelines, and I am not sure of your mechanical background or tools available to you. I skimmed over the whole thread pretty quickly so I could have missed something. Don't be offended.