At 62,000 miles, I'm still running the original water pump on the 2002 PSD. Lucky, I guess. While researching why others have experienced water pump failures I became interested in the bypass filtration units that some PSD owners had installed on their rigs. The big diesel rigs have run coolant bypass systems for years. Probably as a cost savings measure or the fact that the trucks are considered Light Duty, Ford chooses not to put a coolant bypass filtration system on the 7.3. After installing bypass filtration, these PSD owners claimed extended waterpump life by removing silicon (sand) from their coolant system. It wasn't until I changed my thermostat to the 203 degree F unit that I realized just how much of a problem these silicon are in diesel engines.

Previously, I Changed the thermostat.

To change the thermostat, I had to drain a couple of gallons of antifreeze from my radiator so I could remove the thermostat housing. After bolting it back together and returning the antifreeze to the expansion tank, I couldn't believe what I found when I got close to the bottom of the bucket! This is a lot of sand! I could only imagine what it was doing to the seals and bearing in my waterpump. The next day I went shopping for bypass parts.

The components

I was able to get fleet pricing on a coolant filtration kit from CarQuest ( Part # 89019 ) of $20.15 and some great pricing on spare filter elements ( CarQuest 89070 -- WIX/NapaGold 4070 ). Filtration units can have elements pre-charged with SCA additives for PSD's with the green coolant and non-charged elements for those who have the gold coolant. My PSD came factory with the gold. The filter head has a cast mount on it but there was nowhere under the hood to bolt it directly so I was going to have to fashion a bracket. A piece of 3" strap found in the shop should fit the bill.

Ready to finish

After cutting and bending the strap to fit on the left radiator bracket, I was ready to sandblast. The filter head was a green color that I didn't feel would be a good look under the hood so I need to clean it off also.

Finished mount

Both the bracket and filter head was powdercoated with a textured black finish and bolted together.

Pressure side

There is a convenient 3/8 NPT tap on the side of the thermostat housing that can be used for the 'inlet' side of the coolant filter. The 3/8" hose was covered with plastic flex loom material to protect the hose from chaffing.

Mounting the filter

The spot I choose to mount the filter was directly over the radiator bracket, using the radiator mounting bolts. In this picture you can see the inlet coming to the filter parallel to the top radiator hose and the return line being tapped into the expansion tank hose.

Tap the tank

The return or 'outlet' side of the filter is tapped into the radiator return line to the expansion tank. I would have preferred to find a simple 3/8" hose barb tee but I had no luck during my shopping trip, this will have to do.

Element Removal

In this mounting position, things are a little tight but I have found that by reaching in front of the alternator, I can slip a filter wrench on the element and easily remove it.