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Sludge in Coolant

02NavyBlue said:
Right, it's good that you guys encourage changing the gaskets as a preventative thing, but at least make sure the OP knows that's why you're encouraging it, not because we think that's the solution to this thread's problem. It wasn't exactly worded that way but it comes across.

He said the coolant is actually brown, that's usually due to mixing coolants. If it's still red/orange with a bit of sludge at the top it's from air.
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Scottydoggs said:
the lim gaskets should be done on general principals really. they are failing as we speak.

if you do the job yourself and shop smart, you can get it done for around a 120 in parts or so.
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i kinda did say that^^^^
 


Scottydoggs said:
i kinda did say that^^^^
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Ah done as "general principals". Interesting.

Anyway to the OP, a through flush will be needed to get as much of that sludge out as possible. You can use a flush chemical to help break up the sludge. I know prestone makes it, and some people just use tide with good results.

And yeah, check those gaskets and replace if they're plastic, but I could tell this to everyone on the site.
 
A thorough flush is in the plans, and may switchto the green, hhaven't decided. I will get the lim ordered and get that done too. I'm still waiting on the title from the auction house, so have time to get all the fluids changed and the lim before getting it on the road. Thanks again guys.

matt
 
flush it to just water before the lim job, you'll be dumping the coolant when you do the lim, then add 1 gallon of green straight antifreeze, not the 50/50 crap. when the lim job is done.

green is easy to deal with later on, dex is not always to be found so easy in a pinch, the green stuff is every where. super markets, small markets and such if stuck in a bind.
 
orange57 said:
So when looking over the car last night, the coolant appears to be brownish, and when I remove the raidator fill spout there was what looked like oil sludge on the cap. I read on here it could the the trans cooler leaking into the coolant. is there a way to check this before just blindly replacing a radiator?

Also saw some people mention the LIM, is that the lower Intake Manifold gasket? How difficult is that to remove and replace on an 04 GTP? Is there a write up?

Thanks,

matt
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orange57--

Your number one suspect is and should be Dexcool. It gunked on me completely, twice, within a thousand miles.

I suggest sticking a garden hose in one end and opening the plug on the other, running it for an hour or two while you grab a beer, and then coming back. It must have taken me a dozen flushes to get the crud out completely.

Then switch to the conventional green, and never look back.

I wouldn't immediately suspect the LIM unless you can first and foremost rule out Dexcool, although it's a good idea to replace it eventually in either case.
 


Like some other guys said, you probably just need to flush out your coolant system. My 98 gtp is the exact same way. A mechanic who helps me with my car troubles told me that he and I are going to take out the radiator and flush it out along with other stuff I can't recall. Long story short, it's no biggy. It needs fixed, but it shouldn't be an immediate priority. My car's been doing it for about six months now. Still no problem. Just waiting for time to get around to it.
 
Well once dex cool has turned brown and is all gunked, I believe it has lost its anti rust/corrosion properties, so I'd flush it sooner than later.
I flushed a gunked system once, I did a good job with a garden hose flushing and back flushing. About a month later you could still see specks of things floating in the green coolant I switched to because pieces were breaking off of the sludge in the system. That's why I'll always add just water after the first flush, add a cooling system cleaner or tide, and drive it like that for a week to break up the gunk. Then flush again and add green.
 
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What I noticed is Dexcool turns brownish as the pH drops. Right from the bottle it is 8.5 or so, and after time it gets more acidic as the pH drops. I've seen it as low as 6.8. After talking to some people I found that Dexcool has an organic buffering system (not organic as in green, but as in using carbon). Now organic buffering systems have a tendency to break down with 1. time and 2. heat. The perfect storm inside a car's engine. I don't know if this is right or not, but it seems to me that acidifying the coolant over time would hurt some of the components in the cooling system with the most vulnerable failing first, the plastic gaskets in the LIM. Also, not all substances experience the pH scale identically. Some substances natural pH is above 7 (this is called the pka) so a drop in pH below the pka is like getting into a progressive acid bath, the lower you go the more acidic it seems to you.
 
After witnessing first hand what dexcool does when air is introduced to it I will never use it again. Gunks up everything and a pain in the butt to clean up!
 


Dorman 47065/Napa 660-1736, they can be found in the HELP section of most parts stores. or ask for them, on the back of the package it says what year cars they are for.

they also sell new aluminum elbows now. Aluminum Coolant Elbows these are now in parts stores as well, not all of them but some carry the new metal ones. or can order them.

aluminum-coolant-elbows.jpg


the how too http://www.grandprixforums.net/how-change-coolant-elbows-49779.html
 
Thanks Scotty. Got everything ordered today from rock auto, except the elbows, they are from amazon. I plan to tackle flushing, changing gaskets and some other items in the next week or so.
 
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