4440 headgasket

I am having trouble with my 4440. It blew the head gasket a while ago and I tore it down last week.

It got new shims for the cylinders and it was installed by a JD mechanic 2000 hours ago. I don't know why it blew the gasket now but I'll have to measure the cylinder heights.

The gasket is blown between two or three cylinders and exhaust gasses pressurized the cooling system and some very little amount of water got into the oil while it is standing. Didn't change the color of the oil but an analyze showed it.

1. I could get two different gasket kits for this engine, both original JD, both containing the same gaskets but for two different prices. The gasket I have had in it the last 2000 hours is from the cheaper kit. It is a fiber type with steel rings around the cylinders and orange rubber around the water jackets.
What part number is the best gasket for this engine?

2. Head bolts, I ordered new ones, are there only one option for these bolts? I have heard that the changed over the years?

3. What are the most up to date torque specs for the head bolts? What are the height specs for the cylinders?

Maybe you, TimS, can help me with your experience? All mechanics who worked on these tractors when they were new are retired and I don't want to do this again.

Thanks!

and it's a 1978

I have never needed to shim a liner,yet,,How much time is on your engine,did you mill the head last time, and did you use new head bolts?? I have been using the Deere head gasket, new head bolts and milling the head just enough to be sure it's flat, I torq the head in 3 steps,and I pay a lot of attention to that..I mark the bolts as I go to be sure..

Yes, last time the head was done it got milled down. The machine shop said that it was almost perfect to begin with. New bolts was used as well. Thats about 2-2500 hours ago, it has 10300 hours total right now and liners, pistons and bearings got 4-4500 hours total.

I were thinkin of not having the head milled this time? Or would it be wise to have it done? If so, then it is the 3rd or 4th time...

I am taking the head to JD now so that they can remove the injectors and test them.

If you go to get a gasket set take the serial number with you as there are several different gaskets for a 466. I would pay close attention to the liner standout although as Tim said, cannot recall ever shimming any. I have on rare occasions swapped a liner into a different bore to get a nicer fit. I also never reuse a head bolt. Its an extra cost but I believe its worth it. Always check that the right length bolt is being used and be sure to check that the hole and threads are cleaned well.Some will cringe at this but I always use a light coat of permatex on these head gaskets.

Ill have the head machined tomorrow anyway, feels better.

I've also heard about permatex... Which one? And where do you use it? Just around the liners? Both sides?

Have you been doing that for a long time? If I'll have to remove the head again in the future, is it possible without it sticking to the permatex?

And yes, new bolts will arrive on Wednesday, new bolts last time as well. I'll cut a grove in an old bolt to clean the threads with. I will also get the injectors tested and adjusted.

Yes cleaning the head bolt holes is good and make sure they are blown out clean, it is possible for fluid left in the hole to kinda make a Hydraulic action and blow the bottom of the hole out..

I actually know a man who destroyed the block by not bleating the holes from oil so I'll definitely use air for that.

The head is getting the seats recut since some of the valves had been sinking. One valve had to be changed, other than that the head were in very good shape according to the shop. Injectors opened at the right pressure and spray pattern is good.

Question, which are the latest torque specs for this engine? JD-dealer gave me these numbers:
1st round 140 NM
2nd round 193 NM

Are these really correct? I'd add a round at 80 NM or something myself, to make it a three step torquing. Should there not be degrees? This was taken from the manual that was printed for the tractor when it was new, they didn't have any later ones. Can you confirm that they are correct?