Some notes on head gasket swap issues
Well, I am nearing completion of my head-gasket swap, and came across some annoyances to pass on for those who might be doing one in the future. Most stuff is pretty conventional, but some odd stuff. I know some of you are planning it, so here goes.
Oh, this is all from my '94 NAS D-90.
1. 12pt bolts on the oil pump and valve covers. If you have a box full of 6-pt stuff, you will need at least a 5/16 12point wrench (not sockets, wrench). The valve cover size I haven't figured out yet, I'll let you know when I get that done.
2. ARP head studs do work when installing the heads in vehicle. However, if you leave the exhaust manifolds attached to the exhaust, you need to follow a specific sequence. Install the lower row of studs, (the bottom 4 that are only on a 3.9 not a 4.0). Then set the gasket and head onto the block. After the head is on, you can install the upper 10 studs through the heads just fine. ARP gives torque specs on the box, lines right up with the Rover specs.
3. Also, if you use the ARP head studs, you need to use the older style manifold gaskets or trim the newer ones. The connecting piece on the newer 1 or 2 per side gasket will interfere with the studs, since they sit higher than the original bolts.
4. More ARP. The alternator bracket will need to have 1 hole enlarged where the original head bolt also had a mounting stud on it. You won't be able to put a nut on that one, but since it bolts to the head in 3 other places, it should be fine.
4. No F'n drain plug on the radiator! Be prepared to make a mess. Oil continues to drip from all over the place too after you drain it, mostly from the oil cooler and timing cover.
5. The wiring looms for the injectors. Each side also has a connector for a sensor on it, that is the same connector as the injectors. Mark the sensor connector to avoid problems.
6. You can swap cams with the block still in the truck, but you need to remove the radiator and the grill. It's actually an easy cam to swap, the nose is long enough and you can see the cam bearings, so it was very easy to pull the old one and install a new one.
7. You don't need to remove the pulleys from the crank dampener. I just took out the center bolt and it came right out. Very odd was that I didn't need a puller on it, it wasn't a pressed fit.
8. I used the composite head gaskets on mine, the gaskets needed to be trimmed slightly to clear the lower row of head bolts.
Thats all I can think of for now, more when I think of them
My oil line fix
My 100k stopped odometer fix
Brace for impact, I'm in a "modifying mood". Massive thread count inbound.