Diesel RV Club, an FMCA Chapter

Technical => Cooling System => Topic started by: wvabeer on August 19, 2017, 03:28:27 AM

Title: 1999 cummings 300 in a Spartan chassis coolant question
Post by: wvabeer on August 19, 2017, 03:28:27 AM
 I just purchased an older motor home with low miles 38000 miles I found after bringing it home the coolant reservoir empty. I topped it off with new Prestone. I though later I may have screwed up. What kind and type of coolant should I use?
Title: Re: 1999 cummings 300 in a Spartan chassis coolant question
Post by: Brett Wolfe on August 19, 2017, 07:30:07 AM
There are two "types" of coolant approved for HD diesel engines:

Low silicate coolant for diesels with added SCA (Supplemental Cooling Additive)

The newer generation OAT'based coolants w/o SCA

Though Prestone does make these, "regular" Prestone for gasoline engines is not acceptable.

With the cost of cooling system components, if you do not know the kind of coolant and/or age, best advice is to flush and change coolant.

Brett
Title: Re: 1999 cummings 300 in a Spartan chassis coolant question
Post by: wvabeer on August 20, 2017, 10:26:54 AM
I added a quart to the plastic overflow bottle
Title: Re: 1999 cummings 300 in a Spartan chassis coolant question
Post by: Brett Wolfe on August 20, 2017, 12:40:27 PM
If only a quart, and if you have not started/stopped (warm up/cool down) the engine too many times, you might just drain the overflow and refill.  If you don't know what coolant you have, just add distilled water.

But, again, test the coolant to make sure it has not aged out (acidic, improper SCA concentration if older-style coolant, inadequate freeze point).
Title: Re: 1999 cummings 300 in a Spartan chassis coolant question
Post by: wvabeer on August 20, 2017, 03:47:50 PM
It was tested this march, per receipts from Cummings service
Title: Re: 1999 cummings 300 in a Spartan chassis coolant question
Post by: Brett Wolfe on August 20, 2017, 04:07:00 PM
What were the results:

SCA concentration:
pH:
Freeze point:
Title: Re: 1999 cummings 300 in a Spartan chassis coolant question
Post by: wvabeer on August 21, 2017, 02:58:07 AM
 It just said that it was tested and was within specs.