gunk on bottom of coolent overflow bottle

[BK]

At the 1st coolent change I went with prestone's 5year/100K antifreeze. It filled the bill to what Cummins recommended.

I'm due for another change, not waiting 5 years, but every other.

This coolent has been in there for just a shade over 2 years.



I've seen my coolant level in the overflow bottle change, but never become low.

The truck hasn't been driven in ~ 12 hours, I was just checking under the hood and noticed the level was at the add mark.

So I checked all the hoses and couldnt find a sign of a leak.

While I was under the truck, I shined my flashlight up at the overflow bottle and I noticed that on the bottom of the overflow bottle, theres some sort of dense deposit. Just above that, where there's clean coolent, light passes through... but not at the bottom.



I've seen headgaskets go before and I've seen what it looks like to have oil floating in the overflow bottle and coating the sides, but not some layer of gunk on the bottom of the overflow bottle.

The coolent looks clean, dont see signs of oil floating on top.



As anyone else seen this in theirs?



Thanks

Bob

 

[BK]

bump

 

[RustyJC]

Originally posted by BK

At the 1st coolent change I went with prestone's 5year/100K antifreeze. It filled the bill to what Cummins recommended.

Is the Prestone ethylene glycol or propylene glycol? Does the bottle say anything about it being a "low silicate" formulation? Can you get a wooden paint stirrer or yardstick and reach into the overflow bottle to get some of the "gunk" - is it oily (i. e. , like engine oil sludge)? If not, it could be from the additive package in the coolant.



Rusty

 

[BK]

Thanks for the reply Rusty. .



From the jug:

what's in it , as written:

Ethylene Glycol

Diethylen Glycol

Disodium Sebacate

Water

Proprietary corrosion inhibitors



Says:

Designed for aluminum and brass radiators



Contains no Phoshpates, nitrites, silicates, borates, or amines.



From what I remember reading, need an antifreeze that Ethylene glycol based, not propylene glycol based, right? or did I #$4 up?

And again from my CRS memory, thought Cummins recommend low silicates and such?

Did I do wrong?



Boy paint sticks aint long enough for that jugs. Found a piece of flat steel... gently got it down there. The sludge aint very thick, a thin layer on the flat bar. Doenst feel slippery nor does it feel grainy. I only feel the slipperiness of the antifreeze. I only smell antifreeze, sorry didnt taste it

After a few tries it stired into the anti freeze thats in the jug and changed it from orange to brownish, brackish.

No oil slick noticed even after stiring it up trying to scrap some off the bottom.



This is the 1st time I've used the prestone 5/150 stuff, at the same time I used it in my wifes car.



Whats your thoughts?



Thanks

Bob

 

[Jar Head]

Re: Re: gunk on bottom of coolent overflow bottle

It's just casting flash and junk. Mine was the same way. Don't worry about it. The bottle pops right off the fan shroud with a screwdriver. Rinse the bottle out and refill with fresh coolant and eveything will be fine.

 

[RustyJC]

The owner's manual recommendation is for a low-silicate ethylene glycol coolant, although there's probably nothing wrong with a propylene glycol coolant (less toxic, but lower specific heat means less heat transfer).



Does the gunk appear to be iron-based? It could be from iron and other chemicals in the water if you mixed the coolant with tap water, or from residual iron in the cooling system.



If you don't want to dump the coolant, I'd clean out the bottle and see if it comes back. If it does, the corrosion inhibitor package in the coolant is probably gone, and I'd change coolant if it returns.



JM2CW



Rusty

 

[BK]

Rusty - Jarhead...



Thanks, makes a lot of sense.



I'll try a test with a magnet for giggles once the stuff settles again.



Man that would stink if the corrosion inhibitor additives were gone allready. . stuff is supposed to be good for 5/150K.

I got 2. 5 and 20K. (hasnt been my daily driver for the last 1. 5 years, makes more sense now). Didnt plan on keeping it in there for 5 years. . just 2 , but thing happened this fall that I didnt want to spend the monies on flushing and changing the fluid. . sounds like it may have been a bad desicion.



I guess with the darker green prestone I used to always run, it was just never seen.



Thanks

Bob

 

[TXRam]

Check out this thread ...

https://www.turbodieselregister.com/forums/showthread.php?threadid=32521



I think this is discussing the same thing.

 

[BK]

Mine's brown in color.

No globlets. . but it does mix reall easy into the coolant and will settle to the bottom.

I'm going on 3 years of owning the truck. After just a few months of owning it, I read that the DC coolant was high in all the things Cummins says the coolant should be low or free of and it wasnt good for the water pump. So I drained and flushed the block.

By reading that post it sounds as if over time the casting will leach some of the "liquids" used in the production process causing funky stuff.



It's starting to make sense that it ain't much to worry about. Seeing and oily film , I'd be at the dealer ASAP. But this stuff is different and I just wasnt sure. I've seen the headgasket go and get oil floating and combustion by products (carbon, black) settle to the bottom of the overflow. . but the brown stuff had me going.



Frankly with the brownish color, I'm believing the rusty seniment theory... maybe stuff from the casting (idea from the thread of the link) flushing it'self out.

Well I lost today to appointments, and the weather is slipping away, start with rain tommorrow. Winter mix that day after and so on. . so I guess the next reasonable day I'll flush and clean and put new and do the T-stat at the same time. . what recent horror stories about them...

 

[BK]

timely arrival of TDR magazine...

Ha. . got THE magazine today.



On page81 Loren Bengtson summarized his research on Antifreezes. Seems Cummins "best "brew" is a low silicate antifreeze that meets ASTM specification 4985 criteria... . "



Besides having an email into Prestone about using their 5/150 in the Dodge CTD, I did find their list of specs that it meets and the above is listed.



But is low silicate as recommended by Cummins better than no silicate (as the Prestone 5/150 is)?