I changed my low coolant sensor today, I noticed that there was what looked like large grain sand inside the sensor. I am going to flush the coolant anyway, but it worries me.

I dont think that any of that stop leak stuff was used in the car, it was under warranty before I bought it, and I doubt it leaked coolant anyway.

anyone else notice something like this? it cant be normal can it?

 

I noticed a type of snady build up on the coolant level check dipstick. Supposedly it is the little aluminum pipe that runs under the battery for the reservior tank causes the reaction that makes that junk.

My dad had one overheat because of so much build up. I took mine out and washed it out and ran pressurized water through the tube. I don;t know if that is what you were talking about but if so hope it helps. <img src="gr_stretch.gif" border="0">

 

What you are probably seeing is casting sand that was not gotten out of the block before it was put together..

 

Big shoe, early version of Dexcool from GM had problems with coagulating and plugging heater cores, flush cooling system and fill with new Dexcool, never mix green anti freeze with Dexcool.

 

If you are going thru the trouble of flushing you may as well put the green stuff in. Dexcool sucks IMO.

 

[quote]Originally posted by blackhawk2000:
<strong>If you are going thru the trouble of flushing you may as well put the green stuff in. Dexcool sucks IMO.</strong><hr></blockquote>


<img src="images/icons/confused.gif" border="0"> <img src="images/icons/confused.gif" border="0"> <img src="images/icons/confused.gif" border="0"> <img src="images/icons/confused.gif" border="0"> <img src="images/icons/confused.gif" border="0">

 

The owners manuel specifically says not to use the {green stuff] I've noticed the same debris in many LS1s. Some more than others. So I didn't worry about it in mine.

 

Bah! Coolant is overrated! Just fill 'er up with water... <img src="graemlins/gr_jest.gif" border="0" alt="[jester]" />

Just kidding! Anyway, my '98 T/A had that sandy brown gunk, but it didn't really hurt anything in the 34k miles I put on it. In my Z28, I run a 20% Dexcool + 80% water/WaterWetter solution. No problems with sandy electrolytic gook on anything with this combo. <img src="graemlins/gr_cheers.gif" border="0" alt="[cheers]" />

 

I disagree that Dexcool sucks, GM just had to tweak formula and when 50/50 formula is used it lasts 5years with no trouble and protects from dissimilar metal reactions in motor. Drain and fill should be good enough to service old coolant in most cases. <img src="gr_images/icons/wink.gif" border="0">

 

In my opinion Dexcool does not have a 100,000 / 5 year life but was "formulated" as if it did to avoid a proposed EPA regulation to implement antifreeze recycling-dumps, like the oil dumps.

Dexcool has a service life that is somewhat longer than the green stuff -- but as GM now advises in 98+ serice manuals you must use distilled water or de-mineralized water with Dexcool. Dexcool is apparently very sensitive to minerals in the water.

The "sand" reported in this topic is mixture of Dexcool and aluminum plating out in the solution due to a galvanic reaction, where the coolant carries an electrical charge. Aluminum, which is most of the block, is very conductive but where the coolant becomes more conductive part of the engine's charge is grounding through the coolant.

A GM service rep wrote to me privately and said, You can add an extra ground cable, but I haven't because I'm not sure what part of the engine has the greatest voltage potential. I decided the practical course of maintenance was to change out the radiator portion of the coolant once a year, which is about a gallon of coolant, and always use distilled water.

I run 10% Dexcool and Water Wetter, and I drain the radiator part of the coolant once a year. I think that this is enough to keep the coolant fresh and non-galvinizing.

I have not done any long term studies on this subject, but I had a '95 3.8 liter that had so much aluminum-orange-coolant-sand running through the Dexcool coolant that the water passages in the water pump case perforated at 60,000 miles and 4 years. Note: the upper manifold in the 3.8 leaked and I added tap water and Dexcool at least once a month because the warranty-work on the leaking manifold was crap. We have a lot of dissolved minerals in the tap water here. I was very pissed at GM as a result of the problems with the '95 3.8, and I researched Dexcool problems very closely at that time.

[ February 21, 2002: Message edited by: TomBusby ]</p>