Engine Coolant Color Change

wolfe10 wrote:
The "usual suspect" when color is off is that they did not flush out all the old coolant, so you have some old and some new. Not a big deal if staying with the same coolant, but it IS a big deal of one is "regular low silicate for diesel" coolant and the other is an OAT-based coolant.

I had this when we bought our current coach. Previous owner paid to have system flushed and change from regular to OAT (Cat ELC). Me, being a (not so) trusting soul, I pulled a sample-- color was not strawberry as it should have been, but strawberry with a green sheen! So, I flushed it myself and went back with ELC.

For techs working on trucks, having this problem on a motorhome is not uncommon. Instead of 6' of heater hose, your motorhome has 50+'-- much harder to flush.

I considered doing the work myself but I just did not have time before we leave on our first long post retirement trip. I discussed their flushing process with their service manager and he understood the challenges with getting a good flush with a class A motorhome (they work on a lot of motorhome). He even cautioned me that the labor would be pretty extensive due to need to do repeated flushing.

My system is 26 gallons capacity total and they put 23 gallons of coolant in it. If they flushed adequately, the remaining 3 gallons (assuming CC's volume spec is mostly correct) should have been clear water. Considering what I paid to have this done, I would certainly expect them to re-do it if that is what is necessary. I will wait until I hear from Cummins Filtration. Perhaps they will pay for a chemical analysis of the coolant and, if it proves to be a mix of old and new, will support a re-do at no expense to me.