SCAs and Fleetguard test results

a few things:

First: Checking my coolant from my petcock valve (93 F250 7.3) and what came out first was a dingy red color, then followed with green. Upon checking the coolant from the rad cap, it’s green. Is the red just rust? Or does that sound like it’s a mix of red coolant and green coolant?

Second: conducted the test and the molybdate was damn near white. Row 0 if not less. With the nitrite color at column E which was most accurate, that put me at 1.2 marked by a black dot on the sheet provided in the picture. I’m planning on flushing the whole damn system anyways, but I’m curious, how does all of this sound? Is this an “oh ****, I wouldn’t drive your truck until you flush that coolant” moment? Or is it okay until my DC-8 comes in the mail and I add some in. This is my daily driver and I love this truck so I’m really trying to avoid any cavitation.

Third: what coolant do I need to mix with DC-8? There’s so much information on the internet for this stuff, I swear you can read one thing and then read the complete opposite in the same forum thread. I’m considering getting my hands on CAT ELC but until then, what will the DC-8 mix with safely?

The red out of the bottom just sounds like rust residue that settled at the bottom of the radiator. Mine has had that when I've drained my system, nothing to worry about.

If you'll only be running it a few more days until you do your flush, I wouldn't stress over it enough to park it.

If you go with CAT or any of the Fleet style ELC diesel coolants it will already have all the SCAs added, no need to overcharge it with additive. When you flush, don't forget the plugs on either side of the block to get all the old stuff out. Personally, I've just been running regular old green coolant with a bottle of NAPAKool added until I got the right reading on the test strips. Check it every year and add a little to charge it up when needed.

Is the product you ordered DC-8 or Motorcraft VC-8?

Aren't the test strips product specific?
fleet (precharged) don't need testing iirc...

ih8minimumwage said:

The red out of the bottom just sounds like rust residue that settled at the bottom of the radiator. Mine has had that when I've drained my system, nothing to worry about.

If you'll only be running it a few more days until you do your flush, I wouldn't stress over it enough to park it.

If you go with CAT or any of the Fleet style ELC diesel coolants it will already have all the SCAs added, no need to overcharge it with additive. When you flush, don't forget the plugs on either side of the block to get all the old stuff out. Personally, I've just been running regular old green coolant with a bottle of NAPAKool added until I got the right reading on the test strips. Check it every year and add a little to charge it up when needed.

Is the product you ordered DC-8 or Motorcraft VC-8?

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Okay cool. Thanks for the information. It’s VC-8.

Edit: just saw that I put DC-8 in the post. That was just a typo

Minuteman96 said:

Okay cool. Thanks for the information. It’s VC-8.

Edit: just saw that I put DC-8 in the post. That was just a typo

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VC-8 is listed as for green or gold coolant, so it's made to add to the standard stuff, not the ELC coolants.

Clb said:

Aren't the test strips product specific?
fleet (precharged) don't need testing iirc...

Click to expand...

Yes exactly. This point seems to get missed a lot but there are two types of SCA. There is DCA2 and DCA4. The Ford stuff is DCA4 and the stuff napa sells is DCA2. Fleet charge coolant is also using DCA2. Both DCA2 and DCA4 have their own test strips.

Diesel extended life coolant or "ELC" is completely different. While they are formulated to prevent cavitation there is no SCA in them. At least not a conventional type of SCA anyway. So you never have to test the level of SCA or add any over the life of the coolant which is nice.

CDX825 said:

Yes exactly. This point seems to get missed a lot but there are two types of SCA. There is DCA2 and DCA4. The Ford stuff is DCA4 and the stuff napa sells is DCA2. Fleet charge coolant is also using DCA2. Both DCA2 and DCA4 have their own test strips.

Diesel extended life coolant or "ELC" is completely different. While they are formulated to prevent cavitation there is no SCA in them. At least not a conventional type of SCA anyway. So you never have to test the level of SCA or add any over the life of the coolant which is nice.

Click to expand...

Wonderful. Well I just dumped two pint bottles of VC-8 in it thinking it was just that starved for SCAs, because I was barely getting a result with the Fleetguard test. That explains why.

Once I have the dough, I’m just doing a complete flush and filling it with CAT ELC. That stuff is just expensive.