Coolant Fill Trick?
Thread Starter
Instructor
Joined: Oct 2002
Posts: 103
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From: Smithfield VA
Coolant Fill Trick?
I changed the thermostat on my 89 vette and the Low Coolant Light comes on when the engine is warm and rev'd up >1200 rpm. I filled the radiator with the thermostat out so the block would fill but with the cap off and the engine rev'd, it sucks the water level low at the fill cap. Tried to pour water in with the engine rev'd and have only accomplished a mess. I figure the whole problem is that the thermostat housing and hose to the radiator is ABOVE the fill cap. So, how is this filled.... or do I wait for a number of heat-up/cooldown cycles to draw more coolant from the expansion tank??
Burning Brakes
Joined: May 2001
Posts: 1,036
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From: Plant City Fl
Re: Coolant Fill Trick? (SkipI)
Replace the thermostat, take the radiator cap off, let the engine idle until it comes up to temperature and the thermostat opens, add water slowly until you get all the air out. Problem should be solved. :yesnod:
Race Director
Joined: Oct 2001
Posts: 12,555
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From: Fear causes hesitaiton...and hesitation will cause your worst fears to come true. Houston TX
Cruise-In IV Veteran
Cruise-In VII Veteran
Re: Coolant Fill Trick? (Bob88Convertible)
Yep, you've got to let the thermostat open and then fill it. :yesnod:
Safety Car
Joined: Jul 2002
Posts: 4,548
Likes: 3
From: SCMR Rat Pack'r Charter Member, Inland Empire Chapter
Re: Coolant Fill Trick? (SkipI)
How much of a bear was it to change the 'stat? It looks like theres a lot of stuff in the way. Not that its a huge deal but if theres a much quicker way Id like to know it of course.
Thread Starter
Instructor
Joined: Oct 2002
Posts: 103
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From: Smithfield VA
Re: Coolant Fill Trick? (DarkHalo)
Actually the thermostat change was easy. You have to remove the throttle body... well actually, I unbolted the throttle body, disconnected the electrical and vacuum connections, left the coolant lines hooked up and swung it over to the passenger side of the engine and held it there with a bungy cord. I drained the block by removing the hose that goes to the oil cooler at the oil filter. Oh yeah, you have to remove the air intake hose and MAF. I did fill it with the thermostat out, and as soon as the coolant filled to the top of the thermostat housing, put everything back together. The whole job took about 2 hours.
Thread Starter
Instructor
Joined: Oct 2002
Posts: 103
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From: Smithfield VA
Re: Coolant Fill Trick? (Rob 91Z07)
I allowed the thermostat to open and rev'd the engine to 1400-1500 rpm and added more coolant. If you rev it higher, the coolant flowing through the radiator splashes out. I did a search on google groups and found numerous posts that simply said it takes a week or two for all the air to work it's way out. Also, I found that the hose clamp for the overflow line was loose at the radiator. That could have been a part of this. Thanks everyone for the posts!!
Instructor
Joined: Aug 2002
Posts: 118
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From: Monongahela PA
Re: Coolant Fill Trick? (DarkHalo)
DarkHalo....If you have a 1991 you can change the thermostat in about 15 minutes! It's a piece of cake. I just removed mine in my 1990 to flush the system and installed a new one.
All you need is a little patience with the forward 9/16" bolt right under the top radiator hose. :D Any questions, IM me and I'll talk you through it.
And follow the advice of Bob88Convertible....He is right on the money.
All you need is a little patience with the forward 9/16" bolt right under the top radiator hose. :D Any questions, IM me and I'll talk you through it.
And follow the advice of Bob88Convertible....He is right on the money.
Safety Car
Joined: Jul 2002
Posts: 4,548
Likes: 3
From: SCMR Rat Pack'r Charter Member, Inland Empire Chapter
Re: Coolant Fill Trick? (SkipI)
Thanks to you and Qwerty111 for the good info. I dont care how many times that I hear that vettes are designed to run as hot as they do it scares the hell out of me seeing it at 200-230 (hard to be exact with the analog gauge) all the time. Im putting in a lower temp 'stat. Prolly 160 degrees as thats what Ive seen others use.
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Drifting
Joined: Jan 2002
Posts: 1,606
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From: Las Cruces NM
Re: Coolant Fill Trick? (DarkHalo)
I like the 180 degree I'm running. It gives the car a chance to get out of the computer's warmup cycle. My car, with the main fan on it's own circuit and set to run at 190 degrees with a thermostat from Empire (autozone carries this brand, they also have electric fans and some other related stuff), runs at about 185 degrees on all but the worst days, even in the tripical, stop and go, 50kmh (about 35mph) speed limits.
Le Mans Master
Joined: Mar 2001
Posts: 7,999
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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
Cruise-In III Veteran
Cruise-In IV Veteran
St. Jude Donor '12
Re: Coolant Fill Trick? (SkipI)
What I did with mine:
Closed it all up including the thermostat housing. A previous owner had a Prestone Flush T added to the heater hose so I opened it up and filled with antifreeze solution after filling the radiator. Closed it up and started the car with the radiator cap off. Idled it until the thermostat opened and poured more fluid in until it topped off. put the cap back on and filled the overflow tank to just above the COLD line.
No low coolant light. Checked it every couple of day for the next couple weeks, did not have to add anything to the overflow tank so it was all good.
Closed it all up including the thermostat housing. A previous owner had a Prestone Flush T added to the heater hose so I opened it up and filled with antifreeze solution after filling the radiator. Closed it up and started the car with the radiator cap off. Idled it until the thermostat opened and poured more fluid in until it topped off. put the cap back on and filled the overflow tank to just above the COLD line.
No low coolant light. Checked it every couple of day for the next couple weeks, did not have to add anything to the overflow tank so it was all good.
Race Director
Joined: Aug 2002
Posts: 13,356
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From: tucson AZ
St. Jude Donor '04 & '05
Re: Coolant Fill Trick? (SkipI)
Your lucky you didn't have to change the water pump.....*******
Stll thinking what would be the easiest way to complete putting on my FlowKooler water pump......What about that lwr. radiator.....darn....tight in these places....
Looks really tough and time consuming..... :eek: :eek: :eek:
Stll thinking what would be the easiest way to complete putting on my FlowKooler water pump......What about that lwr. radiator.....darn....tight in these places....
Looks really tough and time consuming..... :eek: :eek: :eek:
