What am I looking at?

[Willl]

To me the pistons look like bright shiny aluminum

They are definitely aluminum, cause they have to be.

 

[orezok]

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.
View attachment 108693
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.
View attachment 108694
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

Based upon engines that I've rebuilt, the darkened area at the top of the cylinder you indicated with red arrows is most likely caused by the head gasket being just slightly larger than the bore and exposing the metal to heat. The "off center" is due to sloppy fit of the gasket on the studs/bolts.

 

[TYMinColton]

Based upon engines that I've rebuilt, the darkened area at the top of the cylinder you indicated with red arrows is most likely caused by the head gasket being just slightly larger than the bore and exposing the metal to heat. The "off center" is due to sloppy fit of the gasket on the studs/bolts.

That's really interesting orezok. Let me see if I understand what you are saying. Basically, if the gasket was actually "centered" properly over each cyl and the diameter of the cutouts was matched to the cyls, the block wouldn't have "suffered" from excess heat exposure and we wouldn't see the darkened rings. This also means that there is really nothing "structural" would stop me from reboring, if necessary due to rust, etc., to 0.04 or even larger (assuming I can by properly sized pistons).
Thanks!
Pete

 

[orezok]

TYMinColton - take a wire brush (preferably a power one) and run it over the area. It will most likely all turn the same shiny color.

 

[638]

TYM,
You can over bore right in to the water jacket. I wouldn't bore past .040 oversize, and I would sugest you take the block to an automotive machine shop to have bored. To remove .020 with a hone can be done, but it will be a chore.

ron

 

[TYMinColton]

TYM,
You can over bore right in to the water jacket. I wouldn't bore past .040 oversize, and I would sugest you take the block to an automotive machine shop to have bored. To remove .020 with a hone can be done, but it will be a chore.
ron

Agreed. I was merely thinking ahead a couple of steps. I honestly have no desire to bore a block myself. In fact, if possible depending upon the condition of the pistons/cyl, I'll most like hone out the cyls, clean 'em up, replace the piston rings, and fire her up. There's some cyl pitting, but I suspect its somewhat cosmetic and she'll run - just burn a little oil. overhaul kits are available for several over sizes, but they're not cheap!
Thanks for your input - every little bit counts. Learning a ton about engines that will all be useful down the road!
- Pete

 

[barneyrb]

Don't know how much you know about engines, and I'm not trying to treat you like you are in the 1st grade but, don't mix up any rod or main bearing caps as they have to go back EXACTLY as removed. As for hones the "dingleberry" hone leaves a good looking finish but the 3 stone hones will be better in truing a cylinder and removing small imperfections and putting the correct crosshatch in the cylinder. Your head should go to a machine shop for a valve job and resurfacing. I typically use a LARGE (16") mill bastard file to clean the top of the block. Don't use a lot of pressure and do use the fine side. This will tru and resurface the deck without removing too much material. One of the main secrets that my 76 year old (retired mechanic) father always said about building an engine "everything should be clean enough to eat off of". I hope this helps and I'm not trying to be condesending.

 

[TYMinColton]

Don't know how much you know about engines, and I'm not trying to treat you like you are in the 1st grade but, don't mix up any rod or main bearing caps as they have to go back EXACTLY as removed. As for hones the "dingleberry" hone leaves a good looking finish but the 3 stone hones will be better in truing a cylinder and removing small imperfections and putting the correct crosshatch in the cylinder. Your head should go to a machine shop for a valve job and resurfacing. I typically use a LARGE (16") mill bastard file to clean the top of the block. Don't use a lot of pressure and do use the fine side. This will tru and resurface the deck without removing too much material. One of the main secrets that my 76 year old (retired mechanic) father always said about building an engine "everything should be clean enough to eat off of". I hope this helps and I'm not trying to be condesending.

No need to feel as if you're being condescending. I admittedly am a newbie when it comes to engines. I picked up a book on rebuilding antique engines and one of the first basic rules is to keep all the components (bearings, hardware, etc.) that are associated with a given cylinder and valve set together. So, that's what I've done - 20 or so little boxes of well labeled parts! Everything stays together . . .

The 3 stone hone (lots of recommendations) sounds like the way to go and will be one of my next tasks. I finally managed to remove all four pistons this morning and my impression is that there is some minor pitting, but probably nothing that is going to prevent me from just cleaning up the cyls, re-ringing the pistons, and putting her back together. If she burns a little oil - so what? I am actually more concerned with some rust on the crankshaft and piston rods - although not beneath the bearings. I think I could remove it easy enough with steel wool, etc, but only if I'm willing to drop the crank - which I'm not . I'm hoping to keep this an on tractor rebuild as much as possible.

I've already removed the gasket from both the head and block by employing a combination of kerosene, a putty knife, and a wirebrush. Looks quite clean actually and I didn't have to remove much material. This engine was overhauled probably 8 years ago, so things aren't really that bad. The current rebuild is basically due to stuck pistons/rings that resulted from several years of exposure to rain water. I'll try to post some pictures to give you a better idea of what things look like . . .

Getting there, but certainly not an engine I'd like to eat off yet . Any advice on cleaning the cylinders?

Thanks for your input, I really do appreciate your insights into engine rebuilding!
Pete

 

[TYMinColton]

Here are some before and after pics that bring the whole engine rebuild project up-to-date.

The Block before (pistons still stuck).


After piston and gasket removal. There still some work to be done on the cylinders, including honing. Interestingly, the camera flash really highlights some cyl wear that isn't obvious to the naked eye.


Now an example of one of the pistons. Lots of buildup on the oilers (??). Rings will clearly have to be replaced since I broke several freeing pistons from the block.


Now the Cyl head shotly after removal (valves still in place)


And after gasket removal (seems to be hiding as an attachment below, sorry). I probably have another hour of work to get the head clean and shiny. The valves are another problem.Here's a close up of the head with valves removed.


And the valves. Nasty looking. I haven't tried to clean these up just yet, but might give electrolysis a try.


So this is where I'm at. Any thoughts on the condition of the cylinders? Piston? Valves? I still believe that I should be able to hone the cylinders, clean up the pistons and re-ring, and then clean and lap the valves with the head. Thoughts?
Thanks,
Pete

 

[638]

You will want to rent a "SUNNEN" cylinder hone to clean up the cylinders with. When you are through honing and generally cleaning up the block. Wash the cylinders out with hot soapy water several times. You want a clean white paper towel to come out just as clean as it went into the cylinder. Any grit at all will fry a ring set asap.