COOLANT INFORMATION (TOWNSEND)

(A Special thanks to Tom Townsend of Townsendimports.com for the contribution of this data. As always)

It was in the mid 80's that I ran up against Saab freeze plugs rotting from the inside out. This tripped a BIG Alarm for me. It seemed sometime prior to this we had a Antifreeze shortage where prices and the availability were a problem. I used Napa brand with Aluguard at that time because of price, quality and they delivered. When the shortage was going on , I would get a call from Napa that said, "We have 2 cases allotted for you that just came in, its $9.50 per gallon"
I happen to be at the Mercedes Dealer picking up parts when I noticed a whole wall covered by many cases of antifreeze. I asked the parts person if they were for sale. I was told YES "Its $10.00 per gallon. How many ya want?" I Ordered 6 cases. From this time forward the frequency of water pump failure, restricting of radiator coolant flow, heater valve failure and most important, HEAD GASKET AND THERMOSTAT FAILURE just about came to a halt unless it was a new customer or a car I didn't service. In those days I worked on all Imports and targeted the European market.

This is the final case and logic that converted me:
I had a customer that had a 300 SD Mercedes. The only time I seen this car was when you could run faster than it would go or a wrecker dragged it in. The owner was a old man that squeaked when he walked "bad case of cheap ass!" He also had a folder that documented everything ever done to his 300 SD Mercedes. The last time I seen his car, it was towed in because it was overheating. The water pump was leaking. I replaced the water pump and serviced the cooling system, that included replacing the thermostat. At the time I was communicating with this customer on the problem and the estimate to repair, ... I was setting at my work station and examining the service record and noticed the antifreeze was the original, NEVER changed! This Mercedes had just over 100K on the clock. I drilled the owner on the record and confirmed ....This car has never had a Major service. I almost fell out of my chair. Here's why ...... As I was replacing the water pump and THERMOSTAT ... There was NO corrosion what's so ever!!! I kept asking myself is it the Mercedes metal or what ?? Then I remembered the many other Mercedes cases that had what I refer to as the Green Shit in them and sure enough the aluminum at the thermostat housing was very corroded and pitted. That means when I scraped away the corrosion, the cover's sealing surface looked like acid had eaten the metal away.
I had all the physical evidence I needed. My job function is to protect and preserve customers automotive investments. its too bad it took experience to expose what I know today. It sure would be nice to have a GREAT Knowledge to consult with and guide you with the utmost in engineering principle at any price in a professional setting. There are many issues such as the synthetic oil used in Saabs today ....Yep straight from the factory. Its not typical to Saab either. Mercedes has automatic transmissions that have no dip stick or drain plug! Guess what type of fluid they have in them? I bet its Synthetic.

I had a Saab Factory trained technician work with me for 5 years. The second week with me he asked " where are all the head gasket jobs? every week at the dealer we had 2 or 3 come in" I have a database that has every job I have ever done in the last 10 years. On study, the head gasket jobs that I was doing were Saabs I have never serviced or it was too late to do any good. All of my customers still had the old design head gaskets and experiencing no problems at all.
The Study concluded:
All long lived cases were ...
Set to Factory Turbo specs of 82 degrees C.
The thermal fan switch in the radiator that turns the radiator fans on was set to a cooler spec to keep engine temperature down while setting in traffic.
Mercedes antifreeze

Bottom line here is "ALL FLUIDS USED IN AUTOMOTIVE APPLICATIONS ARE NOT CREATED EQUAL"
COOLANTS

Engine coolant should be maintained to promote both its effectiveness and the longevity of the engine and the entire cooling system. Over time, and with those occasional top offs, the coolant becomes unknown and begins to break down. Phosphates and silicates and produced aluminum oxides fall out of suspension building up and promoting electrolysis, pitting of the aluminum surfaces and the main gaskets and seals. The deposits of these phosphates and oxides in the layers of the head gasket splits it like ice in pavement. Concentration becomes unknown and thus its freezing point unknown. Mixing common ethylene glycol and the newer, supposedly environmental friendly, propylene glycol, produces a mix with a specific gravity unreadable by ball drop type testers meant for either one or the other of the coolants. Use one or the other, but do not mix. Because of this, you might want to keep a little of what you're using around, just in case.

We have found increased life and fewer failures of any kind in the cooling systems after using Mercedes Benz factory coolant. It is phosphate free and pH buffered with inhibitors to aid in the prevention of electrolysis. When servicing cars that have been using it, the difference in the appearance of the internal cooling system is noticeable. Upon thermostat replacement, the aluminum is not covered with the white aluminum oxide or pitted from electrolysis as is common with the green coolants routinely used by some.

The coolant of your choice, unless it specifically states otherwise on the container, should be kept at the least concentration necessary to insure proper cold weather protection for its expected needs. As close to a 50% coolant to water mix as you can get is best, as long as the coolant's label's freezing point chart is followed to insure adequate protection. Running pure coolant is not a very good idea, more is not better. Particulates are more apt to form at higher concentrations.

We service the cooling system on our customers cars every 30K miles with a drain, a flush, a thermostat replacement, a tightening of all the cooling hose clamps, pressure test for leaks, inspection of all hoses and replacement of any upper hoses (top radiator and bypass hose at rear of head) that are over three years old, fan operation, coolant refill and relay upgrades.