Teardown

I started by pulling the XJ in the garage and disconnecting the battery. I then removed the grill to give easy access to the petcock so I could drain the radiator (also, it would allow for an easy installation of the trans cooler....more on that later).

After giving it a little while to cool down I removed the radiator cap, attached a hose to the drain, positioned a catch pan and and opened the petcock to let the antifreeze drain out.

***Never open the cylinder block drain plugs, radiator cap or open the petcock while the engine is hot or the cooling system is under pressure. You're likely to burn yourself. Also, antifreeze is poisonous. Children and animals are attracted to it due to the color and odor. If you suspect a child has consumed any antifreeze, immediately call 911 or your local poison control center. Make sure to dispose of it properly.***

While the antifreeze was draining, I took the opportunity to remove the electric fan and mechanical fan shroud. Each is held in place by two bolts into the radiator crossmember on top (three of which also hold the overflow hose in place) and by two tabs into a bracket on the radiator at the bottom. For the electric fan, I disconnected the plug, removed the two top bolts and pulled straight up on the unit to remove it. For the shroud, I removed the bolts, pulled it straight up and placed it over the fan for the time being. Then, after marking where the hood latch lines up, I removed the bolts that hold the crossmember in and removed it. Click on the photo at left for larger image.

Next, I removed the upper, lower and heater hoses. Then it was onto transmission lines. The upper connection was threaded into the radiator, so after applying generous amounts of PB Plaster, a line wrench took it right off. The lower Transmission line was a little different. It was actually molded into the radiator. There was a "quick connect" fitting to connect the line to the radiator. Because of space limitations, there was nothing "quick" about it...but after some cursing it finally disconnected.

Now it was time to remove the radiator. Since the XJ has A/C, there is a condenser that sits in front of the radiator and they are held together on top with a bolted bracket and held together on the bottom with two dowels on the radiator that go through a bracket on the condenser then into dowel holes in the frame. I simply removed the bolts on top and pulled straight up on the radiator to remove it. Then I removed the fan shroud (previously placed over the fan). Now that there was some room to work, it was onto the front side of the engine... Click on the photo at left for larger image.

First, I removed the two bolts holding the thermostat housing on and removed the thermostat. Then, I loosened (but did not remove) the 4 bolts holding on the mechanical fan and the 4 bolts holding the idler pulley on the water pump (Since the belt is holding tension on these pulleys, it's much easier to loosen them prior to removing the belt). Then, after loosening the idler pulley bolt (under the power steering pump), I loosened the belt tensioning bolt until the belt could be removed and followed this by removing the mechanical fan and water pump pulley. Now that all that stuff it off, it was time to remove the power steering pump and bracket. There are three bolts that hold the pump to the bracket and three bolts that hold the bracket to the engine...two to the water pump and one to the engine block. Once these were removed, it was time to remove the water pump. Four bolts and small tap with a hammer later the pump was off. Click on the photo at left for larger image.

Prep and pre-assembly

Now that everything was apart, it was time to clean it all up for the new parts. After stuffing rags in the water pump and thermostat openings, I used engine brite to clean off all the dirt and grime. Then I used a dremel tool to clean up the mating surfaces.

Next it was time for some preassembly: First, I had to remove the heater hose pipe from the old water pump and install it on the new one. So after I removed it, I put it to the bench grinders wire brush to clean it up and then gave it a few good coats of hi temp black paint. While I was waiting for the paint to dry, I cleaned up all the bolts I intended to reuse on the bench grinder. I then installed the freshly painted pipe onto the new water pump using thread sealant to ensure a leak free fit.

Next, I removed the old viscous fan clutch from the fan by removing the four bolts that hold them together and installed the new clutch on the fan. Easy. I then moved onto the transmission line fittings for the radiator. It comes with plugs in the trans cooler and all the hardware needed in a bag. This took a little thought as to how I was going to run the aux trans cooler lines, but I decided to just set it up to mimic what was on the old radiator, of course, using thread sealant when installing the fittings.

Finally, I installed the new coolant temperature sensor into the new thermostat housing. The threads on the sensor came with sealer already on them, so there was no need to add any more.

Now, it was time to get all this stuff installed.....

Transmission Cooler Install

This was a piece of cake...namely cause I've installed one of these before (actually I've installed 4 of these in various vehicles I've owned). It installs in tandem with the existing cooler (built into the radiator) by going inline on the supply tube from the transmission. So first, I needed to determine which line was the feed from the tranny. On the AW4 (like most Chyco transmissions), the rearward line on the tranny is the feed...which translated to the lower line on the radiator. After figuring out all the hose routing, it was time to mount the cooler. I installed it in front of the condenser, pretty much right in the middle...which worked out well since it was dictated by hose routing. Click on the photo at left for larger image.

The cooler installs with a sort of zip strip that goes through the fins of the condenser. Pads keeps the cooler from damaging the fins. Click on the photos below for larger images.