Coolant test…..

[Cuda67bnl]

What say the experts?

[Alpine36]

When in doubt flush it out.
Six gallons Fleetguard Compleat E.G. concentrate, six gallons distilled water and a new coolant filter (non SCA) Do yourself another good, buy a new sightglass for the expansion tank like this one...

[wolfe10]

And, if you need the "easy to do, but takes time" to do a good flush and fill, let us know.


Totally agree, old coolant is a lot less $$ to change than a new engine because of cylinder liner erosion.

[andy29847]

I see a good test.

[HillHiker]

I finally found some unexpired coolant test strips to do a coolant test. Coolant was sourced from the radiator petcock. While the coolant appears to be clean, it looks like it is the older green type. The test strip seem to indicate it is in the yellow zone at 300 PPM. This is in a 2005 alpine with the ISL400. My owners manual specifies the engine coolant capacity as 10 gallons. Given this information it appears that 3 pints of SCA need to be added to get this coolant back into a safe range to prevent engine damage. Or the other option is to drain and flush, then change to a red OAT coolant like Peak global. Looking for opinions. I need to get this done by next week has I am planning to attend the NAPA rally in April and do not want to run the coach with questionable coolant.
Thanks for any replies.

[96 Wideglide]

It's probably beyond 'End Of Life'.

I'd change it!

[andy29847]

Originally Posted by Cuda67bnl

What say the experts?

Not an expert. Revisiting my earlier comment for my own education. I withdraw my earlier answer where I said the coolant looked OK.

I watched this:

https://youtu.be/RrMBCalwOGw?si=tZ6k0ku84RyN8KMR

Confusing to me is results in the "green" mean you need service.

Looking at the test above...

glycol is 60% = good

Molybdate = row 0

nitrate = F

SCA level = 1.6 units per gallon, i.e., needs service

add .5 per gallon using new filter plus liquid to reach desired level.

[andy29847]

Tested my coolant this morning. It looks like I need to add a bottle of DCA4.

[rrthor]

Andy, have you ever taken a test strip and tested brand new pre mixed coolant out of the gallon container. I have used those test strips many times over the years. Even in new coolant I found the molybdate reading to be low. Curious if you have the same experience.

I have been using a coolant testing lab for the last few years. It doesn’t cost that much.

[andy29847]

Thanks for the reply. I had oil and trans testing done when I bought the coach 5 years ago. I didn't find the results to be that useful. Primarily, I was disappointed in the inability of the testing to identify the lube and coolant already in my camper. I decided to change all to give me a good maintenance baseline going forward.

Your statement about the strips doesn't answer many questions. Did you try to compare a "strip" test vs a "sample" test? If so, how were they different?

My concern regarding coolant is mostly about additive levels. Looking at you lab report, I do not see a result for additive levels. Is the test there and I do not recognize it?

[Old Scout]

Hey Andy--I feel your pain. Seems the only sure way to ensure you have the "right" coolant in a recently acquired coach is to flush and change it. Coolant has evolved from EG to SCA/DCA, to Extended Life [EL] eg NOAT, and now OAT. Coolant color doesnt ensure correct type. Labs like JG are inconsistent with coolant results--my opinion. Std coolant application in most RVs suggests once you have OAT in your rig, you are "good for life." NOAT [nitrite] may eventually require a recharge, and SCA/DCA definitely needs periodic monitoring. For me, the other issue is "compatibility." According to some container labels, NOAT and OAT are "compatible with other coolants." But other literature warns of compatibility issues like thickening/sludge and engine damage?

[wolfe10]

Originally Posted by Old Scout

Seems the only sure way to ensure you have the "right" coolant in a recently acquired coach is to flush and change it.

TOTALLY agree!

Coolant cheap-- engines, not so much.

[rrthor]

The point I was trying to make is these test strips are a little confusing, at least for me. Below is a test I made in brand new ES Complete pre mixed coolant using a CC2206 test strip. It looks like it needs to be serviced. My test strip doesn't look much different from yours.

[andy29847]

Originally Posted by rrthor

The point I was trying to make is these test strips are a little confusing, at least for me. Below is a test I made in brand new ES Complete pre mixed coolant using a CC2206 test strip. It looks like it needs to be serviced. My test strip doesn't look much different from yours.

I think I understood what you are trying to say. The poroblem is how to determine what's wrong. Is the antifreeze mixed incorrectly? Is the strip too old? The whole anti-freeze testing thingy is frustrating, no matter which method you use. Wouldn't it be great if there was a simple, reliable, economical test?