All Charged Up Revisited
Q. I read with interest your column on batteries and chargers. Now, I have worked in the service department of a GM dealer but I have never heard the term AGM battery. I checked with a couple of techs and it was new to them also.

Please define your terms in your articles and what is an AGM battery?
Ron Williams
Clovis, CA

A. You're right, we goofed and should have defined what an AGM battery is-it stands for absorbent glass mat.

The automotive battery is an electro-chemical device-it produces electricity by converting chemical energy into electrical energy. In a "flooded" battery this is accomplished with lead plates and liquid electrolyte. In an AGM battery the electrolyte is contained in the glass mats. As a result the acid can't spill or leak out, and the battery can be mounted in any position (although upside down is not normally recommended).

Thanks to their design, AGM batteries don't produce gasses during charging and are virtually maintenance free.

AGM batteries vary in design. Some use flat plates and have a rectangular case like a conventional flooded lead-acid battery, others (like the Optima) have plates wound in a spiral shape which give them a six-pack appearance.

Depends On What You're Filtering Revisited
Q. I was surprised at your slam of the Frantz oil filter (correct spelling) in you recent column. I have sold thousands of them and installed hundreds personally. I have never had a come back.

Your comment about the toilet paper filter is off base. Almost all filters (oil, gas, air filters) have a paper element. Paper is an excellent filter medium even if it's toilet paper in a Frantz Oil Filter or in a similar competitor's filter.

The full-flow systems are excellent as far as they go. At highway speed the average engine circulates all of its oil about once a minute. The full-flow filter has to filter five quarts a minute and at that rate the full flow cannot remove all of the contamination in the oil. That's why you have to change the oil periodically. Oil itself does not wear out.

The Frantz is a bypass filter that cleans oil at one quart a minute. At that rate it does an excellent job. You can even install one on an engine with dirty oil and it will clean it up!

Another advantage with the Frantz is that it will remove water from the oil (water is necessary to form sludge), which the modern full filter element does not do.

The Frantz filter element should be changed each 60 days and one new quart of oil added. The filter element holds about one quart. The fresh quart adds back additives used up during driving. What do you do with the used filter element? Well first of all the top of the element can be read each time to check for moisture or coolant in the oil, metal, or other unusual conditions that will effect the longevity of the engine. The oil flows through the roll top to bottom. A trouble shooting picture guide is included with each unit.

Second the roll can be used to start a fire in the fireplace just be unrolling a couple of inches of tissue and lighting it. Your have a great fire starter that burns about a foot high, burns for about 1-1/2 hours, does not smoke, and leaves no soot. I have done this a hundred times.

The Frantz would be installed in the same way the Speedway beehive filter is installed and is guaranteed to keep your oil clean!! If a Frantz is installed on a new car under warranty we recommend the oil and OEM filter be changed per their schedule so as to not affect the warranty. But be confident that you now have clean oil in your crankcase all the time.

A competitor, Motor Guard, sells many of their toilet paper filters to body shops as they make an excellent in-line filter for the air to the paint spray gun. Remember my comment above about moisture.

Frantz also supplies a larger unit called a three-stacker for diesel fuel filters that outperforms OEM fuel filters. Moisture again, too.

I have installed Frantz filters as oil filters, transmission filters (works great), PCV line filters (yeah, maybe overkill), and as fuel filters. I have seen them on everything from motorcycles to the largest big rigs on the road.
Ron Williams
Clovis, CA

A. We received several letters on our misspelling of the Frantz name, and a second letter from Ron Williams concerning that as well as their performance.

As for the spelling, I should have caught the error as I too installed a number of these filters in the '60s while working in a service station. The station's owner was a fan of the Frantz, and I vaguely remember we made about $3 commission for selling them and doing the installation.

To get a professional on the use of toilet paper as filtering material, we forwarded Ron's letter to our friends at AMSOIL. This is what they had to say:

One of the issues that plague rolled paper filters is that over time due to the lack of good binding resins in the media they have a tendency to create channels within the filter. These channels allow larger particle-size contaminants to migrate through the filter and into the oil stream.
Richard Holappa, Jr.
Amsoil Technical Product Manager:

Today's paper filters usually include a blend of synthetic media (usually 10-20 percent for durability and finer filter capabilities). A pure cellulose media-like toilet paper- disintegrates with water. As Richard said, the media tends to "channel" and then is virtually 100 percent ineffective for filtration.

In the old days it was thought that having a lot of depth, like a toilet paper roll, was the best answer to filtering oil. But a lot has changed for the better because of the new types of paper available (there are literally millions to choose from) and the addition of polymers to their make up for strength and filtration properties.
Karl Dedolph
Director of Aftermarket Products, Amsoil

While discussing the subject with Editor Brennan the practice of starting a fire with a used toilet paper filter caused him to speculate on the number of governmental agencies that would take exception to the practice.

Everyone is entitled to their opinion, and the Frantz certainly seems to have its supporters. For my cars I'll rely on proper operating temperature and a functional PCV system to keep sludge from forming, continue to change oil regularly and use both toilet paper and oil filters for their intended applications.

We would welcome for publication any verified test results showing the effectiveness of oil filters of any type.