ANOTHER coolant question
Thread Starter
Instructor
Joined: Mar 2004
Posts: 112
Likes: 1
From: Welcome MD
ANOTHER coolant question
OK guys sorry for another coolant question I searched a bunch of them and couldn't find an answer - We recently bought a 1996 coupe w/14,500 miles on it, the lady we got it from had all the records of oil changes and when I ask about the antifreeze she said she never had it change, we all know what dexcool does over time lets not go down that road. Temps were high for me but not high for the lt1 I'm learning 200-230 Ok so fast forward I bought a kwiklift (awesome BTW no more jack pucks for the c5) Two new gm knock sensers for good measure, 8 gallons of dist water for flushing, new overflow tank, 4 gallons of 50/50 prestone dex cool antifreeze(YES I KNOW I PAID ALOT FOR WATER
, and a new ac delco rad cap. Did the flush and refill and burped it, temps are about the same 200-220 driving 230 sittiing idle then back to 219 so around the time the fans come on around 223 ?boiling point? the overflow fills completely to the top and stays there till the engine cools down and COMPLETLY emptys the overflow tank, if I add antifreeze to the COOL line after the next run it sucks that dry puts the level in black to the very top. Is it supposed to or normal to completely empty that tank??
, and a new ac delco rad cap. Did the flush and refill and burped it, temps are about the same 200-220 driving 230 sittiing idle then back to 219 so around the time the fans come on around 223 ?boiling point? the overflow fills completely to the top and stays there till the engine cools down and COMPLETLY emptys the overflow tank, if I add antifreeze to the COOL line after the next run it sucks that dry puts the level in black to the very top. Is it supposed to or normal to completely empty that tank??
Le Mans Master
Joined: Mar 2001
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From: Life is just one big track event. Everything before and after is prep and warm-up and cool-down laps
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Cruise-In IV Veteran
St. Jude Donor '12
Just guessing:
something is restricting flow, check hoses & waterpump
Didn't change the thermostat and its not opening, if new could be wrong temp - should be 190 IIRC
Did you pressure test the system?
something is restricting flow, check hoses & waterpump
Didn't change the thermostat and its not opening, if new could be wrong temp - should be 190 IIRC
Did you pressure test the system?
Thread Starter
Instructor
Joined: Mar 2004
Posts: 112
Likes: 1
From: Welcome MD
No I didn't do pressure test should have huh?, I did buy a new gates superstat 180 when I first thought it was running hot but didn't change it when I learned temps were ok. I still think I may have air in the system(maybe?) because when I shut off the engine it sounds like a 5 year old kid sucking milkshake threw a straw
Racer
Joined: Feb 2004
Posts: 345
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From: Sicklerville NJ.
St. Jude Donor '13-'14-'15-'16
No I didn't do pressure test should have huh?, I did buy a new gates superstat 180 when I first thought it was running hot but didn't change it when I learned temps were ok. I still think I may have air in the system(maybe?) because when I shut off the engine it sounds like a 5 year old kid sucking milkshake threw a straw
Burning Brakes
Joined: Sep 2010
Posts: 931
Likes: 382
I just drained, flushed and refilled mine last week. I purged the system (LT-4) at the bleeder valve on top of the thermostat housing and have not experienced any problems.
Also, my temps are exactly the same as your when the fans cycle on and off.
Also, my temps are exactly the same as your when the fans cycle on and off.
Thread Starter
Instructor
Joined: Mar 2004
Posts: 112
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From: Welcome MD
My temps seem to be ok, after I did the change we drove 6hrs round trip before I noticed the overflow was completly empty when cold hopefully I didn't hurt a engine with only 14k on it
temps never went over 230 so... One more thing about the tstat which I'm going to change, if it is stuck OPEN will this cause the flow problem I'm having? Because when I pulled the knock sensors I poured a gallon of dist water in the tank(for the hell of it) and it came straight out the block, is there a bypass or shouldn't the cold tstat keep fluid out of the block?? stupid question?
temps never went over 230 so... One more thing about the tstat which I'm going to change, if it is stuck OPEN will this cause the flow problem I'm having? Because when I pulled the knock sensors I poured a gallon of dist water in the tank(for the hell of it) and it came straight out the block, is there a bypass or shouldn't the cold tstat keep fluid out of the block?? stupid question?
Intermediate
Joined: Oct 2010
Posts: 44
Likes: 0
From: Wilmington NC
Water can flow from both directions. There are no check valves. Water is going somewhere. Either not all the air was out or you are boiling over or you have a leak or worst case you have a blown head gasket.
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Thread Starter
Instructor
Joined: Mar 2004
Posts: 112
Likes: 1
From: Welcome MD
