Pulpy looking flakes in coolant - 2000 Ford Crown Vic

[fofojoe]

2000 Crown Victoria LX, 4.6L with 170k miles.

TLDR: my coolant passes a PH and ratio test, but I have this pulpy looking stuff in it. Should I be concerned?

Coolant -

Test -

I only use Zerex Original Green (ZX001) with distilled water. This coolant meets the spec recommended by Ford, ESE-M97B44-A.

For context, the cooling system currently works perfect but I am concerned with pulp looking stuff in the coolant. I have drained the radiator 5+ times in recent weeks after multiple distilled water flushes and yet the pulp stuff keeps coming back.

I have replaced the heater core twice now. First time I replaced it with a Motorcraft part that failed in about a year from a pinhole leak. I have since replaced that unit with a Spectra Premium heater core (see this thread). It's been about 10 months since that last replacement and I don't believe it's leaking.

I just found the water pump was leaking from the weep hole, and I have since replaced it with a Motorcraft unit. No leaks from that location since.

The coolant level has been dropping slightly (1/4 below full line) and I have been topping it off with maybe 1 cup of coolant. This could just be a small amount of air purging from the system due to the repeated drain/fills, so I'm not super concerned but I'm watching it. I used a vacuum coolant tool to pressurize and fill the system and it held pressure (22psi) just fine. I ran the air pressure for awhile but couldn't get over 22psi. This could be an issue, but I figured it was due to the altitude (4400ft, Utah).

I found this slime/film in the coolant about 6 months ago. I have since drained and filled the expansion tank multiple times and the slime has not come back.

Video from 6 months ago -

The cooling system has worked perfect throughout all of this time. No overheating, heater works great, car warms up fine, etc. Driving in 90F traffic with the AC on, the coolant stays at 188-190 perfectly.

As for the current state of the cooling system, I have replaced the following in the last 30k miles or so

• Radiator
• Upper and lower hoses
• Water pump 2x (Motorcraft pumps both times)
• Expansion tank
• Expansion tank cap (pressurized)
• Heater Core (twice.. hence my question)
• Heater core hoses
• Intake manifold (Ford Performance, not Dorman)

As for the coolant itself, I have flushed 50+ gallons of distilled water through the system while I've owned it between multiple flushes. I also did use the Motorcraft brand flush (VC1) chemical right before the 2nd heater core replacement and followed the instructions to a T. Flushed with even more distilled water after that.

As you can see, I have replaced the heater core twice now. First time I replaced it with a Motorcraft part that failed in about a year from a pinhole leak. I have since replaced that unit with a Spectra Premium heater core (see this thread)

I believe the Motorcraft unit failed due to electrolysis from my mixing of Zerex/Motorcraft VC5 coolant (I had a bottle of Motorcraft, filled the rest with Zerex), and an incorrect ratio of coolant to water. The car never overheated during this time. In my defense, both coolants meet the exact spec listed on the sticker in the engine bay (ESE-M97B44-A), but I have since learned that even mixing within spec between brands can cause issues.

I have since remedied that by running only Zerex green, 50/50 with distilled water. I have pumped out the overflow tank and refilled with Zerex 50/50 about 10 times in the last year, and drained my radiator and filled again with Zerex 50/50 4 times. Verified with test strips as well. I can confidently say my coolant is only Zerex 50/50.

I have tested my coolant maybe 10 different times now (I have too much free time and test strips are cheap) and it's always tested with the correct ratio and ph level.

My concern is with the heater core. I REALLY REALLY don't want to pull the dash every year so whatever I can do to keep the coolant in tip top shape is worth it.

So should I be concerned with this pulp looking stuff in my coolant? Or is a pH test and 50/50 ratio show that I have nothing to worry about?

Should I flush with distilled water and convert to G05?

 

[Analog-1]

Could be anything it's a 24 year old engine. Those cars while were nice in there era are now money pits. I would flush it one last time and forget about it.

 

[K-Man]

The "pulpy" stuff could be particles of silicon sealant that broke off after being used to seal the parts that were replaced, such as the water pump.

 

[fofojoe]

Yeah I am definitely not looking for perfection, just curious moreso.

All this work has been done by myself and hasn't cost much besides my own time.

I'll just live with it.

 

[ripcord]

I'm going to go with it probably being residue that was adhered to the inside of your overflow bottle and all your coolant changes helped it break loose.

 

[loneryder]

I've seen that stuff before. Other than drain and refill, didn't do anything about it.

 

[Coolant Kid]

That is silicates, one of the drawbacks of using an IAT coolant like Zerex original green. Best thing to do is remove the thermostat housing, take out the thermostat, flush with a garden hose until the water runs clear, then refill with an extended life coolant like Napa 1EXT (use concentrate and add 50% of the system capacity). Don't bother with distilled water, this coolant is silicate/phosphate free and tap water doesn't cause issues.

 

[bullwinkle]

G-05/Premium Gold works really well in original green cooling systems-has just enough silicate to work well. Or use cheap Peak 10X & don’t look back.

 

[fofojoe]

Yeah the Premium Gold was a common recommendation in the Crown Vic world. I'll consider doing that down the road. For now I'll just keep rocking the green.

Appreciate the insight everyone.

Fortunately the extra Zerex Green I have won't go to waste if I switch, as I'm putting together my 1968 Chevelle and my BluePrint 383 uses the original green.

 

[Fordiesel69]

Being a crown vic collector and owning upwards of 30-50 (lost count), when ford was using green coolant, quite often they would place a stop leak pellet in at the assembly plant (heard this from a fleet mechanic) to make sure there were no warranty leaks. Also conventional green coolant did have dropout issues where deposits were accumulated thoughout the system.

On police or civilian models there is an oil filter adapter on the drv side of engine and the antifreeze will never go into the oil, but a little oil can make it into the coolant when the gasket begins to degrade. This gasket will last 15-20 years, and is not as much miles as age. Plan to replace at some point.

I stopped using the old skool conventional green in the crown vics and switched to motorcraft premium gold / g-05 as green does not seem to last. At this point, DO NOT FLUSH with anything. Just ride it out till the heater core fails. At 170K it is on borrowed time now.

 

[Falcon_LS]

I would suggest installing something like a Gano coolant filter in the upper radiator hose to collect all the debris.

 

[fantastic]

G-05/Premium Gold works really well in original green cooling systems-has just enough silicate to work well. Or use cheap Peak 10X & don’t look back.

Can't help but to think about all the Power Stroke owners that would do anything to get rid of that Gold coolant. The Nitrites didn't hold up to EGR heat. Now, these crown Vic's may do just fine but there are great universal coolants these days. Possibly better than green though? I prefer Nitrite free.

 

[fofojoe]

Quick update, just purchased 3 gallons of Zerex G05 concentrate so I'll be changing from the Zerex Original Green here soon.

I plan on doing a thorough distilled water flush first, but just incase there's a teeny bit of Green still in the car it sounds like Green and G05 are not a problem if mixed.

Was looking at my coolant while flushing my brakes and decided I'll finally go for it.

My plan is to do multiple straight forward distilled water drain and fills with the thermostat out until I'm getting clear water.
Then I'll drain as much water as I can and refill with G05 Concentrate and verify the ratio with test strips.

 

[fofojoe]

Looks like I picked the perfect time to switch coolants. The local Advance Auto is going out of business was 50% - 80% off everything.

$13 for a gallon of G05 Concentrate, so I might own 5 bottles now

 

[fofojoe]

Finished swapping to G05 today.

Flushed out the old green with about 20 gallons of distilled water, both by pouring it into the thermostat housing and letting it flush out the lower radiator hose and by filling with distilled and running up to temp, then draining multiple times.

Got a ton of the silicate, crud and gunk out. I've flushed a ton of distilled water before so overall it wasn't that gross.

That big container is the bulk of the silicate that came out. There's more that came out too in the actual coolant that drained out to be recycled.

The vast majority of the coolant that came out was still bright green. The photos are just the crud that I found from the process.

Super happy with the results so far. Tested and verified 50/50 ratio with coolant test strips. I'll test again after a couple days of driving.

Planning on doing drain/fills every 6-12 months going forward to stay on top of it. At less than $20 per drain/fill, it's worth the cost to me.

Also I just enjoy this stuff