Hello All -

Recently acquired a new to me D2 3J #4346. Overall seems like a good unit.  Undercarriage at 50% or better.  Pony has 90# compression.

Was sold as a good runner, but diesel engine was stuck.   It was supposedly "recently free".  Anyways, I pulled the head to inspect and found what appears to be dead and decayed mice and their droppings, urine etc in 2 of the cylinders.  The sleeves don't appear excessively worn, but the pistons are stuck from this mixture.  There was a lot of evidence in the head, and some of the mix must have gotten through the open valves down into the bore.  

It is currently soaking in a 50/50 diesel/ATF bath.  Plan would be to fire the holes as well to expand the bores and then stick the head back on to retain the sleeves and roll it over.  Once free, I would pull the oil pan and pull the pistons out the bottom and re-ring them, then pull the head and hone the sleeves and reinstall the new piston/ring assemblies.  

Rings appear to be called out as:
5B907
6B2171
6B2133

Only 2171 shows as available through CAT parts.  Any leads on where to source an entire ring set for this D3400?

Any comments or concerns with the overall plan?  Am I asking for an impossible job to pull and install pistons in frame?  Any input is appreciated.

Thanks - Chris

My advice is keep it simple Chris, unless you love hard work and spending money, you are off to a good start with the diesel / ATF soaking, you can clamp those cylinder liners down by using some steel offcuts, large washers, and the head studs, so you can watch your pistons move. I'd get some suitable emery cloth and hand scrub those bores clean of any rusty crud, wipe them clean, then try and roll the engine backwards after a good soak.

If you jack the tractor completely off the ground you can then roll the tracks with a suitable long bar wedged between the track plates, or if you don't want to jack her up, put the tractor in 5th, and very gently have a buddy pull her a few inches backwards with a winch block or slow strong vehicle. If you can go backwards then forwards very very gently, to "bump" those pistons free, you will be good to go. If they don't pop loose, light a fire in the bores, use a 50:50 oil and diesel mix, with a rag as a wick.

Once you have the pistons loose, you can then see if the liners are badly damaged, or they need a hone, or they are OK. If they need a hone, you can simply run a thick bead of grease around the outside edge of the pistons with them at bottom dead center obviously,  then hone the bores and give them a good clean out after.

Cat cylinder liners are made of the hardest steel on the planet, so don't be nervy, in fact Cat used to suggest using the powder kitchen cleaner Bon Ami poured down the inlet manifold, as a good way to bed in new rings and liners if they hadn't settled in on their own and were burning oil or slobbering!!

Once you get everything loose and clean, put her back together and get her out in a field working hard for a few days, you might just find you have solved all your problems. If, after a few days hard work you find she is burning a lot of oil, or slobbering badly, or hard to start, then by all means get a set of rings for her, contact Florin Tractor Parts in Sacramento, if they don't have them, they will know who has.

Now just to clarify, I'm no top flight Cat Mechanic like a lot of folks here, just a simple fella without a fancy workshop, but I have dragged a few dead Cats home over the years, one, a stuck 3 cylinder RD6 diesel that I couldn't get loose after several weeks of diesel / ATF down the bores, I filled completely to the top with used engine oil and let that sit for a few days so every internal part of the engine, like the crankshaft and camshaft, and timing gears, all got a good soak, and that worked. It took about 160 litres of old oil, but that is a big ol 9 litre engine!

Those early Cat diesels are a low compression diesel, and there is a heap of rings on the pistons, 4 compression and 2 oil rings, so even if your top ring might be nasty, you still have 3 more good compression rings under it, and I'm always amazed how well a worn out Cat engine starts and runs!! It's not unusual to re-use the head gasket too, if it looks alright, just give it a light coat of Permatex Aviation Gasket Sealer.
Good luck, and as I said, keep it simple initially.
Mike

Try Dana or Dennis at Florin Tractors in Sacramento they have a lot of nos and aftermarket parts.

Regards

Just had a look at the Cat parts store, they have them in stock and a change of part number, see

attached. 

Regards 

Gentlemen -

Thank you for your input and responses, I appreciate it. More info to come in the upcoming weeks I hope.

Chris

If you do need rings Chris, that first one you list, 5B907, you need to add a zero to that part number for it to work in 2022, it is now 5B0907, the Cat part search function only works with a minimum of 6 digits.

I use both the Cat Dealer and the Machinery Trader website to search for parts, it shows who has those parts all over the world, and will usually show any updated or alternate part numbers.

I just had a quick look and the first 2 rings are available at Florin Tractor Parts and other suppliers, but the last one looks harder to find. They will be out there, if not off the shelf, there are piston ring companies that can supply them, I've had new rings made for my dead Cats.
Mike

also try any good engine rebuilder that does industrial and commercial engines you never know what is available and can be made work. take a piston and rings with you. they might even have a listing with hastings or ACL. i wouldnt mind betting the rings were made for cat even back then just like the ball and roller bearings were made by hyatt bearing co.

ive had succes with a couple of air compressors goin into the local engine rebuilder he supplied me rings for a mazda that fitted and worked just fine.

another way to free a stuck piston is bolt a plate over the bore that is drilled and tapped for a grease nipple and use the pressure from a grease gun 10 thousand psi will get it moving to do a multi cyl you would have to undo the big ends so the rods could clear the crank. it would be a one at a time job.

we loosened a single cyl diesel with diesel and a block of wood. after removing the head and filling the cyl with fuel, each day top up the diesel and give the wood a tap with the 4lb club hammer. the wood was the drift and cushioned the piston. took a week or so and then one day it went down and came back up.

and cat wasnt the only one to suggest bon ami i heard that elsewhere too.