John Deere 1050 Engine Opinion

TimberHole · Feb 20, 2018

The last head I pulled had a crack in each of the three chambers. The cracks were near the hole for the injector and all three chambers were cracked in exactly the same place. The old time machinist grumbled something about "they almost all crack there". I asked him if he could repair it and his response was, "of course I can". He pinned the cracks and all is good. Thank goodness for the old timers that really know their stuff.

kleinhhl · Feb 22, 2018

Well that's encouraging news... one of the cracks appeared to be a spider pattern but the other two were simple cracks... the machinist at my shop recognized the head immediately as a Yanmar so hopefully he's able to fix it as well. If not, it looks like a reconditioned 3T90T-J head is between $700 and $1000.

kleinhhl · Feb 24, 2018

Hey Timberhole, do you happen to remember or know the dimensions of the head studs for these 950 & 1050 tractors? My measurements indicate a definite 1.5mm thread pitch but the diameter seems to be 15mm which is an odd size metric stud. I can't find any actual thread chasers or restorers in M15x1.5 size. I'm a little hesitant to use a regular cutting tap to clean the stud holes in the block for fear of ruining the threads.

TimberHole · Feb 24, 2018

I have a couple leftover studs that I replaced and I'm measuring the same thing. I'm headed to the hardware store, I'll take a stud and see if I can match it. I just cleaned the external threads with a wire brush. I double nutted a stud and ran it in and out a few times with some penetrating oil to clean the internal threads. I would also be very careful using a tap as you definitely don't want to remove any material

TimberHole · Feb 24, 2018

Definitely M15x1.5.

kleinhhl · Feb 24, 2018

Okay, thanks... I'll use that method to clean the threaded holes in the block. I'm just waiting for the machine shop to get back to me about the head. They were just finishing the hot tanking on Friday and told me the magnaflux would be done by Wednesday of next week.

I plan on measuring the rod bearings with plastigage and pulling the sleeves/pistons/rods next weekend. We've had lots of rain here this past week and this weekend so it makes progress hard.

kleinhhl · Feb 28, 2018

Today I was able to measure the bearing-to-journal oil clearance with plastigage for all three rod bearings. They all measured within 0.003 in which is within the JD 1050 spec for new parts (0.0016 to 0.0035 in). The wear tolerance is 0.005 in. Bearings looked good with minimal scuffing.

I was also able to pull the first piston and sleeve. The sleeve actually looks pretty good with minimal pitting. I'll have to measure the bore to see if it is within specs. The piston and rings look good too. The sleeve o-rings were toast but I'm guessing by pulling the sleeve, they would get somewhat destroyed in the process. The sleeve o-rings looked like every other o-ring and gasket on this tractor that I've replaced since I bought the tractor... baked, dry and cracked.

I'm still waiting for word from the machine shop on the head. They were supposed to be done today.

TimberHole · Mar 1, 2018

Hopefully your sleeves mic good. I didn't see the pitting on my sleeves until I cleaned them up. Mine were pitted near the top oring.

Are you replacing the rod bolts? Everuone I talked to said I should so eventually I caved and bought new bolts. I'm still not convinced the old bolts weren't ok. I did notice the manual didn't mention replacing these bolts. It did specifically state the flywheel bolts were to be replaced which makes me think the rod bolts may not need replacing since it wasn't specifically mentioned. I'm not convinced all rod bolts are tensioned to the point they are stretching.

TimberHole · Mar 1, 2018

A little thread drift.........

My front hubs (MFWD) were leaking like a spaghetti strainer. I've been working the last few nights to reseal. It's amazing to me that the gears look new after all these years and 2,800 hours. These are tough old tractors and well worth the effort it takes to maintain them.

kleinhhl · Mar 1, 2018

I have the rod bolts on the list of parts for the engine rebuild but I'm not sure I need to replace them either. The torque spec is 47 ft lbs and they appear to be M10 bolts but I'm not sure what class (10.9, 12.9, etc) they are. They are about $11.50 a piece...

I'll have to clean everything up and look closely for pitting too. It would be quite a bit in savings if I didn't have to replace the sleeves.

I have to reseal the front hubs and axle on my MFWD as well. I've been putting it off until the engine was sorted out but I know that is next in addition to re-sealing the Selective Control Valve for the rear hydraulic remotes.

By the way, this is the hydraulic joystick I've been considering for control of the front loader to free up the rear remotes: 3 Spool 25 GPM Joystick Loader Valve w/Grapple | Directional Control Valves | Hydraulic Valves | Hydraulics | www.surpluscenter.com

It would give a third function to control a grapple or angle a snow plow. I would plumb it in before the rear remote SCV via the power beyond port.

Also, got a call from the machine shop while writing this and they say the cracks in the head through to the valve seats and quoted $1200 to fix. I can get a fully loaded brand new head from Hoye Tractor with valves / seats installed for $950... bummer.