Another dumb coolant question.

[BigSkyBob]

I thought I had a reasonable understanding of the coolant in my engine (2006 ISL 400 in a 2008 coach) but after reading until my head ached I'm now confused. I'm told I have Texaco 50/50 mix with added SCA's that was the factory fill. I checked my coolant today and I have 2.4 units of SCA's so that's cool. But the test strip reflected the absence of molybdates as this pad on the test strip remained white. So my question is, if the SCA's fall to an unacceptable level do I add DCA2 that contains nitrates or DCA4 that contains molybdates? I understand the benefits of the DCA4 additive but can I add this when there are no molybdates currently present in the system?

[BigSkyBob]

I thought I had a reasonable understanding of the coolant in my engine (2006 ISL 400 in a 2008 coach) but after reading until my head ached I'm now confused. I'm told I have Texaco 50/50 mix with added SCA's that was the factory fill. I checked my coolant today and I have 2.4 units of SCA's so that's cool. But the test strip reflected the absence of molybdates as this pad on the test strip remained white. So my question is, if the SCA's fall to an unacceptable level do I add DCA2 that contains nitrates or DCA4 that contains molybdates? I understand the benefits of the DCA4 additive but can I add this when there are no molybdates currently present in the system?

[Camelot Camper]

Bob,
As I suggested here, you really need to be speaking with the ladies at Cummins Filtration Technical Support (800-223-4583 opt 1, 4, 3). They are the experts for your engine coolant far beyond anyone can do for you here.
CC

[Lukeaa]

CC,

Why were you checking the coolant in your 2007 coach?

Mine is also, a 2007 ISL, and I had assumed that like my Honda toad, that I should not have to worry about the coolant in my coach for a couple of years. Am I wrong in that assumption?

[Camelot Camper]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Lukeaa:
CC,

Why were you checking the coolant in your 2007 coach?

Mine is also, a 2007 ISL, and I had assumed that like my Honda toad, that I should not have to worry about the coolant in my coach for a couple of years. Am I wrong in that assumption? </div></BLOCKQUOTE>

I drained a gallon from the radiator lower front petcock, tested, added DCA4 to the overflow tank, started engine, and poured the drained gallon back into the overflow tank. This ensures the DCA4 gets mixed into the coolant.

Our 400 ISL is a 2006 pre-emission engine even though our Camelot is a 2007, but I wanted to find out the state of the SCA early to avoid any issues as the test kits are cheap.

CC

[BigSkyBob]

Lukeaa, I was told to check the SCA's every six months with Fleetguard test strips in the CC2602A test kit. The Texaco coolant has a 24 month service interval and should be checked every six months if my understanding is correct. As CC suggested, I'm calling CFTS to further enhance my understanding of the chemistry involved.

[Lukeaa]

I will see if I can pin down anyone from Monaco at the Coming Home rally in Salem next month. They need to give new owners some specific details on the coolants used and the needed maintenance intervals if anyone is having coolant failures or issues. I have not heard of any. My Monaco manual says see OEM manual and the Cummings manual says 60,000 miles or 2 years, drain, flush, refill.

[Diplomat Don]

Lukeaa....This is one of the issues I did'nt want to deal with anymore. For about $120.00, I changed over to the Final Charge (O.A.T.) coolant. It eliminates the need to check the SCA's anymore.

[Sixpack98]

Don,
Were you able to 100% Final Charge? If so, where? I have not found it anywhere and will probably go with FleetGuard's OAT technology. It's even a little bit of a challenge to find 50/50 FC.

mark

[bborc]

I just changed out the coolant in our 07 Knight. It was built on a 06 chassis and test strip showed low on additives. Changed out to Final Charge, found at Tractor Supply.

[BigSkyBob]

I am the OP for this thread so I'll post an update. I spoke with the charming gals at Cummins Filtration this morning and was told the following. I have Texaco 50/50 mix with added SCA's that must be checked every six months. I told her I had 2.4 units as per the CC2602A test strip. She said I could continue to test SCA's until they fell to approximately 1.5 then add DCA4, that contains molybdates, which is five units to bring the SCA's up by .5. Then use Cummins ES Compleat OAT Converter to convert the system to OAT which would then have a 300,000 mile service interval. But the SCA's still need to be monitored every six months but small price to pay in my view. The Cummins OAT converter is CC2778 ES Compleat OAT Converter.

[Diplomat Don]

SixPack98.....I looked everywhere for the concentrate and had a difficult time just finding the 50/50. Just for the heck of it I checked Pep Boys and found they sold the 50/50 by the case.

I was a little concerened about being able to drain all of the coolant out of the MH and then replace it with the 50/50. After worrying about it, I decided that most dealers probably wouldn't be as thorough as me and not even get it close. I found two petcocks, one on the engine and one on the block (ISL). I drained and flushed three times. On the third time I measured how much I was able to drain out. I was able to drain one gallon shy of my capacity. I filled the system with the 50/50 and will keep an eye out for a gallon of the concentrate. Eventually when I find some I'll drain out a gallon and add the concentrate. This should bring me pretty close to 50/50.

We just returned from a 2500 mile trip through California, Oregon and Seattle through some pretty good heat towing a 4550 truck. My coach actualy ran cooler. That may sound weird, but I've read that the O.A.T. coolants can actually cool better. My temp didn't move off of the 190 mark through the entire trip, including the grades through Oregon. On the way home we pulled the I-5 Grapevine into So. Cal in mid afternoon in 90 temps. The coached maintained 50mph and about 2/3rds of the way up the gauge moved to 205 degrees.