zr1mike

For those who have never had the cooler out, there is a 1/8" pipe plug with a hex for an allen wrench. It's on the passenger side manifold at the bottom. I had the cooler out a few times and decided to make this more accessible. You can do likewise. Remove the plug and clean the threads (q-tip and solvent). The following Ace Hardware items give sufficient clearance. Use 1/8 brass short nipple with hex for wrench part 17-8601 122A. This goes in place of the plug. When sealed with whatever your preferred sealant is on both ends, lower the cooler with nipple into the grommet. The nipple will extend all the way thru the grommet as it already has a hole thru it and so does the plastic radiator lower shroud. Some threads from the other end of the nipple will be exposed below the shroud. Next, thread on 1/8" brass street elbow 17-9071 28A. I found 2 different styles in this number, the one you want is the fully machined elbow, not the cast one which is larger and will not give enough clearance. Thread the elbow on to the nipple using a wrench. The lack of clearance will not allow a full turn on the wrench to get the elbow tight. Insert an allen wrench INTO the elbow and you can manipulate the allen wrench adequately to tighten the elbow further. You'll need sealant on the male threads of the street elbow which is now pointing toward the rear of the car. Insert 1/8" brass coupling 17-9221 33A onto the threads. You are now past the frame member that makes all this necessary and keeps you from simply removing and replacing the original hex plug. Insert the original hex plug or whatever you wish for the future draining procedure. I want to emphasize that the ACE elbow is the smallest one I could find so that this whole thing will work. I found similar things at Home Depot but these allowed the elbow to smack the frame member and would cause the cooler to be damaged whe things bounce up and down. The nipple I mentioned is slightly under 1 inch long and has a hex for a wrench in the middle, better than using pliers. My cooler was tapped a little to deep and required some thought so the nipple sealed tightly. I used Locktite thread sealer w/ teflon. It sets up tight as it dries. I normally like teflon tape and realize some people have difficulty with it but it works if done properly. The cooler will hold about 3/4 qt when filling thru the bottom hole when the line assembly attaches. Use rags until you get the knack, it's messy if you overfill. Incidentally, I drained the full cooler after the lines were disconnected and the cooler plugged. I filled a quart bottle to the threads.

While on the subject, I flushed the cooler several times while out using solvent, then a garden hose and finally acetone after I found the cooler still didn't dry 100%. Denatured alcohol will absorb water as well. Finally compressed air.

I found that although my crankcase oil was always clean, the cooler oil was like Hersheys syrup! As I suspected due to high oil temps while racing, the cooler was along for the ride, essentially just blocking the air to the radiator. I got the thermostatic control (essentially a copper encased paraffin pellet like a radiator therm uses) for $27.00 and that will be the next project. I wonder how many people have a dead and dirty cooler like I did? The part I got is 10067599, might be discontinued one day. Nice to have one. $34.44 list

All this applies to a '90 year, Don't know but maybe the 405 hp cars got a slightly different cooler design, I didn't check part numbers.
Now those with ambition and mechanical ability can drain ALL their oil.