Cooling Question
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Joined: Sep 2016
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Cooling Question
I just bought a 1995 coupe a month or so ago and I noticed the coolant was really bad. Looked like a mix of rust, blood and some mud in the overflow tank. I had it flushed out today because it was so bad. It seems to stay at the same temperatures as before so I am wondering what is normal? Crusing down the road it stays between 197-200 according to the digital gauge and if it idles for a bit it goes to 225 ish. Is this normal or should I be looking at replacing the thermostat or something?
Last edited by Carguytroy1; Sep 21, 2016 at 11:36 PM.
Race Director
Joined: Apr 2002
Posts: 10,036
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From: Anaheim CA
The rusty yucky appearance of the coolant is caused by mixing Dexcool and the older green coolant. It should be thoroughly flushed or there will be future problems.
Your fans are controlled by the ECM. Trust the engineers who programmed the fan turn on temperatures. Generally they are: main fan: 228°. Secondary fan: 238°. If that seems "too hot" to you then you can have the ECM reprogrammed to change the fan turn on temperatures.
Your fans are controlled by the ECM. Trust the engineers who programmed the fan turn on temperatures. Generally they are: main fan: 228°. Secondary fan: 238°. If that seems "too hot" to you then you can have the ECM reprogrammed to change the fan turn on temperatures.
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If that is normal then I am cool with leaving it how it is. I had the dealership I work for clean and flush the system. I went and watched for a little bit just to see if the water they were running through it came out clear and after about 45 minutes it was just clean clear water. Before that it was really nasty. This morning coming to work it ran at 195 then I let it idle in the parking lot for a bit and it was hanging around the 225 mark according to the digital gauge in the speedometer LCD
Last edited by Carguytroy1; Sep 22, 2016 at 11:55 AM.
Burning Brakes
Joined: Jun 2016
Posts: 761
Likes: 66
From: Fitzwilliam New Hampshire
Good to clean radiator fins of dirt and road debris but have to remove it to do it the right way,ac condenser can then be cleaned in car.Its amazeing the junk in there after 20+ years.Did mine,now runs at 186-192 most of the time at 40mph+with 180 themostat
Last edited by A Peter C4; Sep 22, 2016 at 10:57 PM.
Burning Brakes
Joined: Jun 2016
Posts: 761
Likes: 66
From: Fitzwilliam New Hampshire
Mine is 94, green is what it takes from owners manual info, but I used Peak long life all vehicles when I did complete flush with new knocks and hoses and stat and cap also removed radiator ,cleaned crap out of fins with hose and was suprized at amount of stuf plugging fins runs 186-192 most of the time fans have not come on sense I did this,temps stay down now.
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Burning Brakes
Joined: Jun 2014
Posts: 1,020
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From: Connecticut
What you described sounds like what I had when I bought my 96. What I found when I flushed mine was that the bad looking stuff was contained only in the overflow pressure bottle (closest to the windshield). All of the remaining antifreeze looked as good as the new stuff I put back in. As a matter of fact when I took the old stuff in to be recycled, the guy behind the counter asked me what I did with the old stuff because the stuff in the bottle looked brand new.
I did take the overflow bottle out and scrubbed it clean but the rest of the system was fine (and YES I pulled the knock sensors like everyone suggested and nothing bad or rusty came out).
I changed the radiator, water pump, hoses and knock sensors while doing all of this so I saw the entire system top to bottom and nothing seemed to be wrong with the coolant.
When I was done I filled the system with DEXCOOL premix too. Figured if the car lasted 19 years with DEXCOOL already then why change now.
YMMV of course. Good luck!
I did take the overflow bottle out and scrubbed it clean but the rest of the system was fine (and YES I pulled the knock sensors like everyone suggested and nothing bad or rusty came out).
I changed the radiator, water pump, hoses and knock sensors while doing all of this so I saw the entire system top to bottom and nothing seemed to be wrong with the coolant.
When I was done I filled the system with DEXCOOL premix too. Figured if the car lasted 19 years with DEXCOOL already then why change now.
YMMV of course. Good luck!