WC Dilema

    First some history.  This was a family tractor that I started on about 3 years ago as a pandemic project.  It was a nut and bolt rebuild with a new overhaul kit, crank was ground, head was sent to a machine shop and checked out, planed, new valves, new gasket set, etc.  I've been taking my time to do a meticulous restoration, spare no expense!  I finally got the motor back in the frame a year ago, and got it started (by hand cranking), but had to shut it down after a couple minutes of running because it had no radiator or coolant in it.  About a week later I tried starting again after installing the radiator with a new core, new hoses, clamps, antifreeze, but couldn't get it to start again.  It was getting time to work on machinery to go to the field, to get ready for planting, so it got shoved back in the corner of the shop, and left until now.  I finally got the tin work back from a proffesional painter on Saturday, so got interested in getting it finished, because I want it done for a show coming up in June.  We got it out yesterday, and pulled it around the yard to get it started, and after a little tweaking on the carb, it ran fairly well, but I noticed it was pressurizing the coolant in the radiator, and forcing it out the overflow tube before it got much heat built up.  We ran it around for maybe half an hour to get it warmed up, then backed it into the shop and shut it down.

   Checked the oil, and it looked like chocolate milk!  Horrified, I dropped the oil out, after getting about half a cup of antifreeze on the bottom first.  Then I drained the antifreeze out of everything.  Then I put some new oil back in, and tried to crank start to get it circulated in the bearings etc., but not a pop, or any starting attempt.  It was dark, and my pulling help went home, so that's where I left it in the shop.

   Anyone have any suggestions what to do next, before I start to tear down the motor?  We're getting into planting season again, so this will have to be an after-hours project, once I figure out how to proceed.  I'm going to do a compression check on the cylinders to see if they're consistent with each other.  This is a new rebuild which needs to be broken in, so I'm thinking of filling the cooling system with diesel fuel, and doing a pull start again to get it warmed up, to seat the rings.  Dad said they used to do that trick on the new JD 4010's when they came out, because the first ones had head gaskets blowing regularly before they got the uneven sleeve-deck issues figured out.

    It has sat over a year with antifreeze in it, and no external leaks, and the oil looked fine before we got it running.  Like I said, it seemed to be pressurizing the cooling system, so that has to be a cracked head, or head gasket fail, right?  Like I said, the head was all proffesionally checked and redone, and all new gaskets installed, so I'm baffled.  I'm a JD man, so thought I might see if any of you AC guys can set me staight, and tell me what I'm doing wrong!  Thanks!

SEIA Farmer wrote: I finally got the motor back in the frame a year ago, and got it started (by hand cranking), but had to shut it down after a couple minutes of running because it had no radiator or coolant in it....

IMO, that is probably the root cause here.

A full rebuild engine generates significant internal heat when it's in the break-in process, as the parts fit tight.  Add combustion heat to that, and running with no coolant really is not a good idea.

If you're lucky, it's just a head gasket, and all your bearings haven't been ruined by pushing water through the babbit.

I don't recall exactly what I did 2 years ago (a senior moment), but I always use copper coat when installing head gaskets, and I always lube the o-rings before installing the cylinder liners.  What was used for lube, I don't recall, but I usually use whatever they recommend in the instructions with the liner kit.

  I made a flat sanding block from 3/4 plywood and a piece of plexiglass, and sanded the liners and deck down with 150 grit sand paper until I had less than .004 of clearance all across the deck.  After everything was cleaned with brake cleaner several times, I installed a new Felpro head gasket, which looked like a much higher quality head gasket than the one I removed, and took DrAllis' advise, and used the anerobic gasket sealer on both sides of the HG.  Put it all back together, and torqued the head studs to 80 ftlbs.  After another pull start, got it running today, and happy to report everything looks and sounds good, with a few minor antifreeze leaks on the waterpump and rad hoses.  That gasket sealer should take care of the block cracks just fine.  Just wanted to report back, so maybe someone else can use this experience of mine to head off some of their potential problems.    

  Now, the bad news!  After running it at low and high idle for about 30 minutes, or so, it started to labor, then locked up!  Now I'll need to drop the oil pan again, and start checking bearings!  Any advice where to look first?  It was running good, and never really got too hot, so I'm hoping it's just a bearing that had too little clearance, and siezed up from the antifreeze that got mixed in from the first startup.  I'll let you know what I find!  Thanks again!

   The front main was getting all kinds of oil, as it was dripping everywhere when I removed the bearing cap.  The cam bearings were not changed in the rebuild, as I checked the clearances and they were within specs, so I would think they would stay in place after 45+ years.

   I was able to get confirmation from the machine shop that the mains and rods on the crank were turned down .020" when re-done.  Pretty good records after being done 4 years ago!  The engine had been overhauled at some point 50+ years previously because it had the bigger sleeves and pistons when I took it apart.  I kinda remember now thinking that the under side probably needed renewed, while I had it apart, because all the shims had been removed.  I'm a self taught, apprenticed, farm shop mechanic with no formal schooling, just mainly learning from my uncle, and shop manuals.  On the old JDs we worked on, you just checked the rod bearings with plasi-guage, and removed shims from the caps until it was back within specs...but they were a slower running engine!  I've rebuilt several Deeres and a couple Olivers, but this is my first AC.  It's also the first time I've removed a crankshaft and done a complete "underhaul".

    I wish now that I'd had someone like DrAllis guide me through it, because you explain things much more clear than the service manuals do.  I just want to get it to start and run well...it's not going to do any "work" anymore because I'm putting it back on steel rears with roadbands.  I appreciate all you guys are doing to keep the old tractors going, and the hobby alive.

    I want to do whatever I need to get it running well to "play" with.  I'll have a couple weeks to get advice, parts, or whatever I need, because the calendar says it's now time to plant corn!