What am I looking at?

[TYMinColton]

The cylinder walls would be cleaned up with a hone, and if there is not pitting, you could get by with that. I can't really tell from the photos, but to me it doesn't look all that bad.

Good luck!

Thanks. A hone is one of the tools on my list. I should have a much better idea about the condition of the cylinders once the pistons are out. Unfortunately, the "gudge" on the cylinder walls is making it nearly impossible to drive the pistons out through the top of the block. I think I might have to remove the crank shaft and then remove the pistons from underneath . Probably time to figure out how to remove the engine from this bad girl too .

 

[kmdigital]

You can estimate that by just looking at the pics? Impressive . Can I ask how you can tell? Anyway, according to the I&T shop manual the later hundred series tractors didn't have sleeves. Of course the good news is that if I was willing to have the cylinders rebored, I should be able to either find a set of oversize pistons or I could drop in a set of sleeves with matching pistons. Engine rebuild kits of this type seem pretty standard for the 172 Diesel engine.

Thanks by the way. This is definitely the kind of advice I'm going to need. At some point I have to decide whether it's worth it at this point to attempt an overhaul. Obviously, if this block has had it - then that's probably the end of the road for this tractor. . . .

Pete

Look closely at the #1 cylinder picture. I think water set in this cylinder for some time. See the dimpling in the reflection from the flash just above the piston? This should be nice and smooth, and this will be hard if not impossible to hone out. Also, there appears to be a rust pit just to the left of the shiny dimpled spot on the cylinder wall, as well as in that band about 1/2" wide about an inch above the piston where the piston rings had previously polished the wall. This looks like substantially more than surface rust to me. It's hard to tell, but it looks like the rust may be worse further to the right on the wall, but this isn't real clear.

Maybe you will get lucky and it mostly surface rust. However, as I stated, the wall looks dimpled from rust, instead of being nice and smooth.

 

[john_bud]

Thanks. A hone is one of the tools on my list. I should have a much better idea about the condition of the cylinders once the pistons are out. Unfortunately, the "gudge" on the cylinder walls is making it nearly impossible to drive the pistons out through the top of the block. I think I might have to remove the crank shaft and then remove the pistons from underneath . Probably time to figure out how to remove the engine from this bad girl too .

Here's your next thing to try.

Get a straight edge razor blade and scrape the edges of the cylinder to get rid of the gunk and rust. Then get 2 electric heaters and have them about 1foot away from the engine on each side. You want to heat up the block to about operating temperatures, 200F. You want it to be at that temp for 30 minutes! Then try to torque it over. The heating will expand the bores the same way hot water expands the lid on a stuck jar.

Are you keeping the steady pressure on the crank with the jack? You should! Especially when heating it up. Then come by and give a whack with that wooden hammer handle. I wasn't kidding with the 3 pound hand maul either. A 16 oz framing hammer won't provide the oomph to get it rocking. You do need to put some rubber hose on the connecting rod bolts if you have some free. You don't want to nick the crank with the rod bolts!!

If $$$ is more precious than labor time, you can just hone the cylinders out (even with pock marks) and reassemble. It will at least run, even if it has some blow by. Then you can plan out a rebuild with larger pistons. I like to go overbore, but if you plan on keeping it for ever you may want to put in the sleeves. It's about the same kit price either way. Just don't get discouraged or impatient, both can lead to bad things.

 

[TYMinColton]

Here's your next thing to try.

Get a straight edge razor blade and scrape the edges of the cylinder to get rid of the gunk and rust. Then get 2 electric heaters and have them about 1foot away from the engine on each side. You want to heat up the block to about operating temperatures, 200F. You want it to be at that temp for 30 minutes! Then try to torque it over. The heating will expand the bores the same way hot water expands the lid on a stuck jar.

Are you keeping the steady pressure on the crank with the jack? You should! Especially when heating it up. Then come by and give a whack with that wooden hammer handle. I wasn't kidding with the 3 pound hand maul either. A 16 oz framing hammer won't provide the oomph to get it rocking. You do need to put some rubber hose on the connecting rod bolts if you have some free. You don't want to nick the crank with the rod bolts!!

If $$$ is more precious than labor time, you can just hone the cylinders out (even with pock marks) and reassemble. It will at least run, even if it has some blow by. Then you can plan out a rebuild with larger pistons. I like to go overbore, but if you plan on keeping it for ever you may want to put in the sleeves. It's about the same kit price either way. Just don't get discouraged or impatient, both can lead to bad things.

I'm not discouraged just yet, but probably a little impatient . Thanks for the suggestions. I especially like the idea of scraping away some of the rust. Point of clarification. Your suggestion about the hose/tubing seems to indicate that I should disconnect the push rods from teh crank. Correct?

Anyway, we'll see about coming up with some electric heaters (not something I have in stock), but wouldn't heating the block also expand the cylinders inward, making it even tougher to get the pistons moving. I'd think covering the block with ice might shrink the block. . . . Hey, I'm willing to try anything at this point.
Thanks!
Pete

 

[kmdigital]

I don't think you need the heater. But you MUST get rid of that rust before the pistons will come out. As stated, scrape as much off as you can, and I would get steel brush for your drill or die grinder, and polish the walls as well. The pistons will come right out if you get rid of anything that protrudes from the cylinder walls. It will also help you to know how bad the rust and pitting are.

 

[TYMinColton]

20 ways to skin a cat . Thanks for all of your suggestions. Sounds like the consensus is to try and remove as much rust/corrosion as possible (various methods) and then drive the pistons out through the top of the cylinders. Got some work ahead of me this weekend .
Pete

 

[Danno1]

.

TYM,

If you heat the block the outside will expand as will the cylinder walls. IOW, they will follow the outside surfaces of the block as they expand outwards. Hope this makes sense!

.

 

[TYMinColton]

.

TYM,

If you heat the block the outside will expand as will the cylinder walls. IOW, they will follow the outside surfaces of the block as they expand outwards. Hope this makes sense!

.

So, an analogy would be removing a metal lid from a jar. If it's tight, you can place it under hot water and it will become easier to remove. This is because the size of the interior gap of the lid has expanded. However, in the case of an engine that has an iron block and aluminum cylinders? I would think the heat treatment might also depend upon inherent differences in the expansion properties of the different metals. There's probably some law of linear thermal dynamics at work here, but it's been a longtime since I cracked a physics textbook .
Thanks,
Pete

 

[Danno1]

.

Aluminum expands at a higher rate than steel. Therefore, the steel block will govern the size the liners expand to.

Wait a minute, I just read what I wrote! Did you mean alum block w steel liners? If that's the case, then the al block could expand to the point where the steel liners would get loose. Prob have to get it far above normal operating temps to do this though.


VERY aproximately:

steel expands 8x10E-6 in/in/deg F
Alum expands 12x10E-6 in/in/deg F

.

 

[TYMinColton]

.

Aluminum expands at a higher rate than steel. Therefore, the steel block will govern the size the liners expand to.

Wait a minute, I just read what I wrote! Did you mean alum block w steel liners? If that's the case, then the al block could expand to the point where the steel liners would get loose. Prob have to get it far above normal operating temps to do this though.


VERY aproximately:

steel expands 8x10E-6 in/in/deg F
Alum expands 12x10E-6 in/in/deg F

.

I think I'm following you around TBN danno1. Good question about the block. I know that these blocks did not have "liners" per se and were directly bored, however there does appear to be two different metals (based on color) that comprise the "block" and the "cylinder" (see pic). My engine was clearly rebored larger by 0.02 (stamped on the pistons; green), but the bores seem to stay within the original cylinder, but rebore was not quite centered (red arrow), likely intentional.

If you look at the underneath pic I've highlighted in yellow the piston and block. To me the pistons look like bright shiny aluminum; block looks like steel.

I suppose this really doesn't matter for using heat to induce metal expansion, but it's an interesting thought exercise based on several assumptions (never a good mix). Nevertheless, unless I'm mistaken, if you were to heat the pistons directly, being aluminum they would swell up more so than the cylinders and it would be even harder to get them out.

dunno. . danno1
Pete