D15 II Head Gasket Trouble

Following the engine rebuilt, we been putting her all back together and making good progress. Last thing we did yesterday was put in some engine oil to test the pump...(worked perfect), with the head on and all holes plugged, we added enough water to the block to make sure nothing was leaking.

So pulled the drain plug this morning and first thing to come out was about 1 cup water. That was disappointing.

So we pulled the head back off and found a wet head gasket, that delaminated when we pulled it off. Best guess is coolant was wicking past gasket and on into the block. But we have also filled block back up to top to see if any coolant is getting past O rings of the sleeves.

Head gasket came with rebuild kit from Reliance. Rumor has it (now.....after the fact) those are suspect. So looking for a Fel-Pro replacement.

Main question, however is the head bolts, which come in two sizes. One group is 3/8".....4 bolts on right side are larger. My service manual shows torque for all head bolts to be the same.

Have been told that on the WD45 and maybe D17, same thing exists....head bolts are two different sizes but torque for those goes up. Is greater for the larger bolts.

What is the best plan for the D15? Leave them all the same or increase torque for the larger ones?

Am wondering if a person could secure a mill sheet of copper of the appropriate thickness and mill there own gasket then use copper sealer as a work around?

Orangeman

Ive had same head gasket problems on a D17. You can identify the bad head gaskets by the following: the width of the steel fire rings on the BAD gaskets are the same width on both sides of the gasket.

The good head gaskets have a wide width fire ring on the block face, and a narrow width fire ring on the CYLINDER HEAD side. These bad aftermarket head gaskets started to hit the market last December from what i can tell. They do not compress enough under torque to seal. This, in combination with too much sleeve standout from aftermarket sleeves causes coolant leakage! Anywhere you see copper still showing on the gasket means it did not seal under torque on those areas!

The head bolts should be 2 different torques for different sizes I believe although the factory manual says 80-85 for the 7/16 bolts, doesn't mention the 1/2" bolts. The original D15 head gasket didn't have fire rings, but most use the D14 gasket with fire rings.

 

 The gasket should have "This Side up" embossed on it.  It really isn't possible to get it on wrong as there is a long and a short distance from the bore to the edge of the block front and back. 

Replacement head gasket ordered through a local supplier. Gent who is about 80 dropped off a new Fel-Pro gasket. He happened to be the same guy who was trusted to turn down the crankshaft, and is well respected by locals when it comes to engine rebuilds. He is the man.

However, before that showed up, as luck would have it, a pair of alternative head gaskets showed up in shop where wrenching is taking place. Should probably mention that the building is about 45 years old and has been used almost exclusively as an AC repair shop. On any given day, there are from 6 to 8 AC tractors in there in various stages of undress. Currently holding a C, pair of 185's, pair of 190XT's a WD and a 7010.....plus a D15. While sorting through one of several piles of various surplus gaskets, two different Victor head gaskets showed up. No clue as to their origin or history, but there they were.

One is what is believed to be similar to what she was wearing when she left West Allis.....thin and no fire ring. Alternative was a thicker Victor with ring.

When gent who brought new replacement in saw the Victors, his mood improved. Said at one time they were A#1 first choice if you wanted the best. Would be using those if it was his......and no sealant. Says so right on the gasket. He confirmed that was right.

So thicker gasket with fire ring went in, no sealant, smaller bolts torqued to 80 ft pounds, larger bolts to 90 ft pounds and that did it. Held head water for about 5 days with no leaks, so buttoned her up and she is now back together and running.