Installing a Coolant Filter
Paradise Garage

We recommend Internet Explorer set to 1024x768.

© 2000 Brian F. Schreurs
Even we have a disclaimer.

Not sure I want to know where Deer Park water comes from...

Buy our book!
With a brand-new supercharger being installed on the visiting 1995 Ford Mustang GT, there was no way we were taking chances with anything. We want this car reliable and working at its peak.

One area that's not addressed on nearly every car is the coolant. This system, which sees all kinds of insane conditions and touches on just about every aspect of the engine during its circuit, is totally unfiltered! Any garbage in there is free to circulate around until it finds something convenient to stick to, such as a cooling jacket, the thermostat, or the inside of the radiator. None of these situations is exactly desirable, especially with the extra heat the supercharger causes.

We suppose we could come up with some kind of hokey filtering thing, but fortunately we don't have to. A company called Tefba makes coolant filters for a variety of hose diameters, and their 1-1/2" model works dandy. To get one, drop a note to Musselman Distributing in Texas; they'll ship it to you. You'll also need a couple of hose clamps of the appropriate size for the hose.

Measuring the Tefba filter before cutting.
The Tefba filter assembly.
As installed on a supercharged Mustang.
The Tefba filter is a pretty clever design. It fits inside any straight section of existing radiator hose. The filter itself is a stainless steel mesh screen, situated in a V configuration so that the flow of coolant tends to capture particles (rather like a fishnet), which is resting on a platform that can pull out of the housing.

There's no need to undo the hoses every time it needs to be cleaned, either. The Tefba filter has a cap on it, sealed with an O-ring, which is used as the exit for the filter. Really, it's easier to check this filter than it is to check an air filter. And, if you're a lazy bum who can't be bothered to clean the filter with every oil change, there's an internal bypass to prevent 100% clogging. Slick.

Installing the Tefba filter is a piece of cake. You probably don't even need to drain any coolant, but just to play it safe, go ahead and drain it all. Odds are, you need some new stuff in there anyway.

Select a straight portion of the upper radiator hose (you could use the lower hose, but you'll end up having to drain the coolant all the time, which would suck) and line the Tefba filter up next to it. For a stock application, you'd simply mark on the hose where the inlet and outlet of the filter meet the filter body. Masking tape works well. Then use a razor blade to remove that section of hose.

In our case, with the supercharger causing clearance issues already, we chose to leave the entire length of hose in place, which forced the hose to swivel a little toward the driver-side, also known as Away From Supercharger, which is what we needed.

Jam the filter into the hose. Orient it in such a way that the cap is accessible and there are no clearance issues. Since the cap has an O-ring on it, the Tefba filter does not need to be perfectly vertical. In fact, Ford puts the upper radiator hose so close to the hood that the only way we could make it fit was to install it sideways. One alternative, on a car without a supercharger to get in the way, is to cut down the vertical part of the hose at the water pump. This would probably provide the necessary clearance to install the filter vertically on a stock configuration.

Clamp the filter down and refill the radiator with a mixture of coolant and distilled water. That's it! Easy!

Of course, the real question is: does it work? The photos on these pages should speak for themselves. To provide some background, this car is barely five years old (when most manufacturers recommend changing the coolant for the first time), has had its cooling system drained and replaced twice already (this project makes three times), and had its radiator replaced two years ago due to an engineering mishap. In other words, this system is in really darn good condition.

Now go look at the stuff we picked up after a measly 10 minutes of idling. Ten minutes at idle! Heck, the coolant probably wasn't even circulating for the first five minutes!

We checked it again at 200 miles before setting it to a check-with-oil interval. Take a look at that. We don't know what that slimy garbage is, but we're mighty glad it won't be accumulating in our nice new radiator anymore. How much longer would a heater core live if it didn't have to contend with this stuff? If you've ever swapped a heater core, you know it's worth finding out.

The Tefba filter is already picking stuff up, even with just 10 minutes of idling!
After 200 miles, the filter was really getting to work. All this from a cooling system that had just been flushed!

So it's pretty obvious that we really like the Tefba coolant filter. It's such a simple idea, yet it works so well. This should prolong the life expectancy of a host of parts that are a hassle to replace: the radiator, the heater core, and the water pump will see obvious benefits. It could also help prevent water jackets from plugging, and maybe prevent the thermostat from getting gummed up. It's certainly worth the small price of admission to find out.