Chevy = POS; or, How Does Mud Get In My Coolant??

[TC535i]

So, the Tahoe's been spittin up coolant lately, even after being parked. Noticed the temp climbing up a bit at a stop today, so decided to check the coolant level, and it was a bit low. Then I noticed the radiator cap had this crap all over it!

Kinda looked like mud, and had a gritty texture to it. WTF?!?! My buddy claims it must be sand from the casting process, I don't even know WHAT to think, but it managed to clog up the hole to the bypass hose, which could have been causing a lot of these problems.

Anybody else have a better guess as to what this crap in the radiator is???

-Tim

[winfred]

orangey lookin ****? that's the wonderful dexcool at work, i had to do the intake gaskets on the bosses 96 350 burban, it was a bitch and those plastic gaskets are a joke, so is that quick connect heater hose thing on the passinger side of the intake

[Jr ///M5]

Same thing happened to our van....flush it out now, it's not good to 150k miles like they advertise. Nothing is.....

GM laid an egg with the dexcool, the shop told me that if I changed it every 30k miles it would be ok.

Heard a lot of horror stories about that stuff such as winfred mentions, sometimes the shop has to do an acid boil to clean up the cooling system. Ours wasn't that bad. The tech at the shop said that the 4.3 litre Blazers were the worst. He'd seen where they could scoop the coolant out with a spoon....

And think, some people run that crap in their BMW's.....=(

[Bill R.]

looks exactly like sandy gritty mud.. and look in the radiator and its worse just like sludge.. I have changed a couple of radiators on late model big block suburbans along with freeze plugs... Its extremely caustic and like the others say you should flush it out right now... It needs to be a very thorough flush or the same reaction will occur with the new coolant..I would keep flushing the block and radiator over and over with a hose until its only clean water coming out..and then run regular prestone green... Turn the heater on while doing it to get it all out of the heater core or you'll soon find out what heater core leaks are all about on dexcool equipped cars...








So, the Tahoe's been spittin up coolant lately, even after being parked. Noticed the temp climbing up a bit at a stop today, so decided to check the coolant level, and it was a bit low. Then I noticed the radiator cap had this crap all over it!

Kinda looked like mud, and had a gritty texture to it. WTF?!?! My buddy claims it must be sand from the casting process, I don't even know WHAT to think, but it managed to clog up the hole to the bypass hose, which could have been causing a lot of these problems.

Anybody else have a better guess as to what this crap in the radiator is???

-Tim

[TC535i]

Wait, so you guys are saying that's just the normal coolant??

Something definitely plugged up the overflow hose, it was a chunk that looked like a mud-rock or something, I could squish it between my fingers, but it had a gritty substance.

[Bill R.]

get a reaction with the air in the system and the dexcool and it turns into this nasty gritty sludgy crap......Then they tried to claim that someone mixed a conventional green coolant with a oat coolant like dexcool and this is the reaction that occurred... Whatever the real cause its dexcool at fault, flush it all out of the system and you won't have any more problems unless its already eaten everything up...









Wait, so you guys are saying that's just the normal coolant??

Something definitely plugged up the overflow hose, it was a chunk that looked like a mud-rock or something, I could squish it between my fingers, but it had a gritty substance.

[TC535i]

get a reaction with the air in the system and the dexcool and it turns into this nasty gritty sludgy crap......Then they tried to claim that someone mixed a conventional green coolant with a oat coolant like dexcool and this is the reaction that occurred... Whatever the real cause its dexcool at fault, flush it all out of the system and you won't have any more problems unless its already eaten everything up...

Sounds like a plan. Any write-ups on flushing out a '97 'Ho effectively? (Vortec head 350, if that matters...) How long am I looking at? Any special equipment / any tricks?

[Bill R.]

get one of the prestone backflushing kits and splice the tap into a heater hose.. then flush and flush and flush and flush and flush and flush and flush and flush and flush and flush... well you get the idea.... When you see the thermostat you'll probably put a new one in....





Sounds like a plan. Any write-ups on flushing out a '97 'Ho effectively? (Vortec head 350, if that matters...) How long am I looking at? Any special equipment / any tricks?

[winfred]

know of any decent brands of flush solvent? or are they all useless!


get one of the prestone backflushing kits and splice the tap into a heater hose.. then flush and flush and flush and flush and flush and flush and flush and flush and flush and flush... well you get the idea.... When you see the thermostat you'll probably put a new one in....

[Bill R.]

well and he gave me some samples but I haven't had a car to try it on yet..
http://www.bgprod.com/pro_images/products/0540.jpg








know of any decent brands of flush solvent? or are they all useless!

[ryan roopnarine]

i wonder sometimes how my mother's car lucked out so well, if it were my bmw, it would have needed another HG by now....

car is delivered to us (99 ford taurii) in 1999 with 10k and orange coolant

car's tranny is replaced under warranty in late 2k2 because of dealer not putting ATF into it before handing it off to us in 2k1

go to flush rad and replace orange with orange in dec of 2k2 and see there's now green in there, but everything's still stained with copious amounts orange crap, so i know they didn't try more than 1/2 asses worth to get it out

20k miles later, and the only problem with the car is that its using a bit o coolant up in these 95 degree floriduh daze....i guess i need to change a thermostat now, as well as pouring some turpentine/benzene/aircraft remover down into things to clean it out?

[TC535i]

So the kit is something with a couple hose clamps and a few T's and stuff? $4.99, Pep Boys says they have a few in stock. Should I pick up a can of some sort of Flush Solvent, or should I only get the BG one, or... just use water?

[Bill R.]

Let me edit this, I would use water then open the thermostat housing back up since you removed the thermostat prior to flushing... Then inspect the thermostat housing after flushing with water. If you still see a bunch of sludge and gook then I would flush with one of the commercially available flushes like prestone etc...You'll have a hard time finding the bg one unless there's a local bg dist close to you...









So the kit is something with a couple hose clamps and a few T's and stuff? $4.99, Pep Boys says they have a few in stock. Should I pick up a can of some sort of Flush Solvent, or should I only get the BG one, or... just use water?

[TC535i]

Good stuff, I'll have my brother pick the kit up today, got the day off tomorrow so I'll work on it then... maybe figure out how bad I cooked my '86 325es. Overheated the thing (didn't know, temp gauge is apparanty shot...), and the oil pressure light came on... that can't be a good thing. Now it has trouble starting up, and keeps overheating (might be a plugged heater core, I'll just bypass it, the car only cost $900...)

Any writeups on how to flush the Tahoe? Bypass a heater core? Explanations on how an oil pressure light could come on during an overheat, and why the car REALLY doesn't want to start now??? :(

[Robin-535im]

My wife has an '02 Tahoe and the Dexcool has been tugging at my mind lately. I think I might just replace it after this thread!

- Robin

[sbcncsu]

My father-in-law's 99 Bravada decided to plug up the heater core one cold morning on our way to Raleigh to catch a plane. There was no heat at all. When we got back to town and froze our tales off riding back to Wilmington, I vowed to fix it for him. I pulled one heater hose and attempted to flush out the core with water. No luck. I inserted the nozzle from my compressed air line and gave it a bump of air. It blew out the nastiest looking, nastiest smelling precipitate I have ever seen / smelled. It was awful. I went to the Advanced Auto and bought a prestone flush kit and two gallons of antifreeze. I flushed and flushed and flushed and finally replaced it all with Prestone and Distilled water.

A few months later, he took it into the dealer and they noticed the water pump was leaking. They repaired it and refilled the truck with %$*@#@$%%^ DEXCOOL!!!

Awful stuff...