Coolant question.....:

[fkloster]

I have a 1991 Caterpillar (fully electronic) 3176 turbo 325hp (wet sleeve) plant and am happy as a clam with its 1,200+ foot pounds of torque and 51% torque rise. This engine was equiped with a "coolant filter" that my shop tells me with my driving (about 2,000 miles a year) needs to be changed every other year. Apparently it slowly releases attributes that supress "cavitation" on the wet sleeves. So here goes....:

1) Is it ok to mix your coolant w/ tap water prior to filling system?
2) Is it ok to mix your coolant w/ distilled water prior to filling system?
3) Is it ok to flush system with tap water prior to filling?
4) "50/50 Final Charge" ... will my engine use this in its cooling system?
5) Should I be changing my coolant every 2 years? or ???
6) My shop uses a pre blended mix + additives to fight cavitation + new coolant filter when the flush my system every 2 years... should I have anything to worry about?
7) My oil samples all check out fine.

thanks in advance!

[yudamann]

Check with Caterpillar for correct coolant. The coolants used in wet sleeve engines have additives that not only prevent corrosion, but prevent cavitation that is very important. You need the correct coolant to start with. Then you can get test strips to test every 6 months to determine how much of the additive to add. Additive is a small bottle and usually not much is needed for topping off. Serious damage to your very expensive engine can result if cavitation pitting eats through the sleeves. An easy, inexpensive maintenance check that can save you lots of money if neglected.

[RinkersRanch]

First, you must use low silicate heavy duty antifreeze in Cat diesel engines. Automotive coolant has quite high silicate to protect the aluminum components. The silicate will combine with some of the cavitation inhibitors and cause them to drop out of solution. Contaminating the cooling system and reducing the anti-cavitation properties of the coolant additive package.
Now in answer to your questions.
1) Is it OK to mix your coolant w/ tap water prior to filling system?
You should never use tap water in a cooling system of any engine. Too many contaminates.
2) Is it OK to mix your coolant w/ distilled water prior to filling system?
It is best to mix coolant before filling. Use distilled if you must, but you would be far better using premixed Long Life Coolant. Even distilled water has contaminates which can damage the cooling system. The water in premixed coolant is distilled, filtered and treated so as not to damage the system in any way.
3) Is it OK to flush system with tap water prior to filling?
Flush if you have contamination, but if the system is in good shape simply install new coolant.
4) "50/50 Final Charge" ... will my engine use this in its cooling system?
50/50 mix is good for most areas, if i remember 50/50 is good to around -40 degrees F. Never use more than a 60% antifreeze 40% water mixture.
5) Should I be changing my coolant every 2 years? or ???
Using ELC in your cooling system will extend the service of your cooling system. There is a sample/analysis that can be done to keep the coolant at top performance.
6) My shop uses a pre blended mix + additives to fight cavitation + new coolant filter when the flush my system every 2 years... should I have anything to worry about?
What ever you use, make sure you can purchase additional of the EXACT coolant. Coolant's from different Mfg. should not be mixed.
7) My oil samples all check out fine.

A couple of cooling system notes.
No amount of additives can make bad water good. The 'bad' has to be removed before it is put in the system. Use pre-mixed coolant.
The 'pill' in the coolant filter dissolves in the first 30 minutes after installing a new filter. Be sure to use a filter of the same Mfg. as the coolant you use. The additives may not be compatible if brands are mixed.
40% of all engine failures can be traced back to a cooling system problem.