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..

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