8n rebuild help

[fireguyfire]

So my 1950 8n has served me faithfully around the acreage for 10 years or so since I pulled it off of a farm. The engine was stuck when I got it but with some soaking and rocking the rear tires while in gear, the rings freed up after a few years and it’s been fine since.
Anyways, the front and rear seals are starting to weep, and I now have low compression so I thought I would pull the engine apart and install a full rebuild including sleeves and pistons etc and she should be good for another 70 years.
I’ve got the engine apart and on an engine stand, and as usual when working on old engines there are a couple of big surprises!
This engine has been rebuilt at sometime in the past and it now has no cylinder sleeves in it, and has much larger non original pistons in it to compensate that have 4 sets of rings including one ring below the wrist pins.
I seem to remember reading that this was not uncommon on these engines that the sleeves got pulled when they were worn out and larger pistons weee installed.

The good news is that the piston bores are decent with only a very faint ridge at the top, and it just seems that the rings themselves need to be replaced. The rod and main bearings are .010 over and are almost like new which is also good.

So my questions are, has anyone seen this where the sleeves have been removed and larger pistons are installed?
I’m concerned about how I’m going to source new rings for these larger pistons; does anyone have any suggestions on that?
I’m also open to inputs on how to proceed, but if I can source rings for these larger pistons I was planning on honing the cylinders, new rings, new main and rod bearings, new engine gasket set and then put her back together.

Any thoughts or suggestions would be appreciated!

 

[mhb@ufe]

The pistons used for that should be .0825 over size. I see the pistons are available from this site so I would think you could by the rings from this site. That number should be stamped on top of the piston. I would recommend you give them a call.

 

[JJay48]

I have heard of people doing this. I would buy .090 sleeves and have them fitted at the machine shop if it was mine.

 

[fireguyfire]

The pistons all read .110 on the dome

 

[mhb@ufe]

The pistons all read .110 on the dome

That's a new one for me, I haven't seen that before.

 

[showcrop]

I always do what the automotive machine shop tells me. They prep the block, measure everything and source the parts for me so that everything fits together. they even save me money on the parts.

 

[fireguyfire]

So I took a piston by my engine machine shop that is owned by a buddy and my pistons are indeed .110 over pistons. He initially had some hope that what they had used were Ford flathead pistons for a car, but they don’t come in that size either, or don’t anymore at least.

So I now am stuck as to what my options are for this engine. It would be an absolute shame to scrap this tractor over this as the rest of the tractor is really good, but I also don’t want to throw a bunch of money at it either.
I’m open to suggestions on how I might save this thing now that the factory sleeves have been removed and it has been bored out to .110 over.

 

[mhb@ufe]

So I took a piston by my engine machine shop that is owned by a buddy and my pistons are indeed .110 over pistons. He initially had some hope that what they had used were Ford flathead pistons for a car, but they don’t come in that size either, or don’t anymore at least.

So I now am stuck as to what my options are for this engine. It would be an absolute shame to scrap this tractor over this as the rest of the tractor is really good, but I also don’t want to throw a bunch of money at it either.
I’m open to suggestions on how I might save this thing now that the factory sleeves have been removed and it has been bored out to .110 over.

Check with the machine shop about custom sleeves to bring it back to standard or find a used block.

 

[Jim L WA]

So I took a piston by my engine machine shop that is owned by a buddy and my pistons are indeed .110 over pistons. He initially had some hope that what they had used were Ford flathead pistons for a car, but they don’t come in that size either, or don’t anymore at least.

So I now am stuck as to what my options are for this engine. It would be an absolute shame to scrap this tractor over this as the rest of the tractor is really good, but I also don’t want to throw a bunch of money at it either.
I’m open to suggestions on how I might save this thing now that the factory sleeves have been removed and it has been bored out to .110 over.

Hi firguyfire, I don't know how I missed your first post back on the 1st. When I tore my 2N down about 10 years ago now, I found the same thing. What I ended up doing was contacting Egge Machine (not sure of the spelling) in Southern California. I gave the guy all the measurements of my pistons and he came up with a set of rings that were for AMC, Continental, Frazer and Kaiser. Those were all 6 cylinder engines, so I had to buy the set of 6.
You could even send them that photo of your piston.
Give it a try and let us know.

 

[fireguyfire]

Will do, thanks for the advice.