CRG Discussion Forum

Camaro Research Group Discussion => Maintenance => Topic started by: sftibbs on March 29, 2013, 07:17:21 PM

Title: Coolant drain and refill
Post by: sftibbs on March 29, 2013, 07:17:21 PM
I drained the coolant (SB 350) by opening the peacock and removing engine block bolts. Drained about three gallons. When refilling, less than one gallon brought the radiator to full. What am I missing  ???
Title: Re: Coolant drain and refill
Post by: tmodel66 on March 29, 2013, 09:40:49 PM
Have you started it since you filled the radiator? If not the block will need to fill up when you start it. Water level will go down.
Title: Re: Coolant drain and refill
Post by: sftibbs on March 29, 2013, 10:05:46 PM
I have not. I was thinking water needed to get into the block but wasn't convinced I could start the motor with no coolant in the block. As I understand you, I can start the motor and fill the radiator as the coolant goes into the block as the level will go down?
Title: Re: Coolant drain and refill
Post by: janobyte on March 30, 2013, 01:23:38 PM
yes,if you are worried top it through the intake ( thermostat ) replace thermostat ,housing etc... BTY if you are in the habit of draining for winterizing don't forget the heads if you aren't running an antifreeze mixture.
Title: Re: Coolant drain and refill
Post by: JohnZ on March 30, 2013, 05:06:39 PM
System holds about 4 gallons. From an empty system, I usually fill the block through the thermostat opening in the intake until the level comes up, then install the thermostat and housing, and finish filling through the radiator filler neck. Start it, run until the thermostat opens, and adjust final level. After it's cooled overnight, check level again - it should be a couple of inches below the filler neck, where "full cold" is embossed on the side tank.
Title: Re: Coolant drain and refill
Post by: canadair on March 31, 2013, 11:24:01 AM
just remove one end of a heater hose replace  it when then fluid comes out use only distilled  water
Title: Re: Coolant drain and refill
Post by: sftibbs on April 01, 2013, 07:32:48 PM
I filled the block through the thermostat opening and put in a new thermostat since I was there. When I start the vehicle and it gets to operating temp, the engine starts to overheat and the radiator is cold. The radiator was gone through prior to restoring the car and along with the water pump has few miles on it. The thermostat is new? Could it be trapped air in the system? If so, what's the best way to bleed it?
Title: Re: Coolant drain and refill
Post by: Mike S on April 01, 2013, 07:46:16 PM
 I have always had great success with the 'burp' method. While running and hot enough for the thermostat to be open I would grab the upper hose and squeeze hard rapidly many times until you hear a faint burp like sound which are the air pockets finally escaping.

Mike
Title: Re: Coolant drain and refill
Post by: sftibbs on April 01, 2013, 07:55:56 PM
Thanks Mike, with the cap on or off?
Title: Re: Coolant drain and refill
Post by: Kelley W King on April 01, 2013, 08:17:28 PM
Although I have not tried it, there was an article written lately by an engine builder who drills a 1/8 inch hole near the edged of his T-stats when new to help purge the air. I will be trying it soon.
Title: Re: Coolant drain and refill
Post by: Mike S on April 01, 2013, 09:58:04 PM
Thanks Mike, with the cap on or off?
  For mild squeezes I leave the cap off to see if the water level suddenly lowers which would indicate the air ipocket s worked out. Otherwise I'll put the cap on and give it rapid squeezes. It can take some coaxing but I have had this work very well.

Mike

Mike
Title: Re: Coolant drain and refill
Post by: Mike S on April 01, 2013, 09:59:30 PM
Although I have not tried it, there was an article written lately by an engine builder who drills a 1/8 inch hole near the edged of his T-stats when new to help purge the air. I will be trying it soon.
  I have seen thiese already drilled in t-stats from parts stores. That's a good point to bring up however.

Mike
Title: Re: Coolant drain and refill
Post by: JohnZ on April 02, 2013, 02:19:33 PM
I've been doing this for over 55 years now, and have never drilled any holes in a thermostat, nor have I ever had any "air pockets". At the first start cycle after a complete refill, leave the cap off (or loose) until after the thermostat opens and then you can adjust the level.
Title: Re: Coolant drain and refill
Post by: 69Z28 on April 02, 2013, 04:08:21 PM
Just as JohnZ says. I have found on occasion that when filling an engine that is completely empty that air gets trapped inside the block and assuming other places as well. I bought a 69 Judge from a friend back in the 90's and he couldn't get it to stop overheating. Did a little research and found if you leave the radiator cap off and let the engine run at operating tempature the air will enventually be burped out thru circulation as you keep adding fluid. Chevy engines don't seem to have as much of a problem as the Pontiac engines do, at least the ones I have owned anyway.
Title: Re: Coolant drain and refill
Post by: tmodel66 on April 03, 2013, 01:02:00 AM
I filled the block through the thermostat opening and put in a new thermostat since I was there. When I start the vehicle and it gets to operating temp, the engine starts to overheat and the radiator is cold. The radiator was gone through prior to restoring the car and along with the water pump has few miles on it. The thermostat is new? Could it be trapped air in the system? If so, what's the best way to bleed it?

Can you see the water circulating in the radiator? I have always just started it up with cap off. When the thermostat opens the water level will drop. When you add coolant that will force any air out of the system as it continues to circulate and fill the voids with nothing but head pressure from the radiator.
Title: Re: Coolant drain and refill
Post by: sftibbs on April 04, 2013, 03:20:15 AM
No, the water is not circulating in the radiator. I noted today that when the engine gets to running temp, the top radiator hose is cold and the bottom hose is hot. The water in the radiator remains cold.
Title: Re: Coolant drain and refill
Post by: tom on April 04, 2013, 04:27:03 AM
Check your thermostat. If it doesn't open, the upper hose will remain cool, while lower hose will heat up, your motor will overheat. An easy (not real accurate) check is put your thermostat in boiling water. It should open.
Title: Re: Coolant drain and refill
Post by: tmodel66 on April 04, 2013, 01:23:20 PM
I'm not being a Know-it -All  but did you put the thermostat in up-side down? In a hurry to get it put together I have seen strange things happen.
Title: Re: Coolant drain and refill
Post by: sftibbs on April 04, 2013, 02:34:06 PM
Being at a loss I did check the thermostat and it was in correctly. There's no indication my old thermostat was bad as the car ran fine prior to changing the coolant. I bought a new one thinking that somehow the old one was bad (however changing the coolant doesn't make a thermostat go bad in my experience). So at this point, it's hard to believe both the old thermostat and the new one are both bad, but stranger things have happened. I will take the new thermostat out and run a test and update the post. Thanks for all of the assistance.
Title: Re: Coolant drain and refill
Post by: 69Z28-RS on April 04, 2013, 04:26:01 PM
If the water isn't flowing, and the thermostat isn't impeding the flow, then si there anything else that might be impeding flow?  or... Perhaps your water pump isn't pumping....?
Title: Re: Coolant drain and refill
Post by: tmodel66 on April 04, 2013, 05:57:42 PM
If the coolant is not circulating it could be the water pump. Does pressure build up on the hoses when it's running with the cap on the radiator? I mean do the hose feel tight or are they easy to mash on?
Title: Re: Coolant drain and refill
Post by: sftibbs on April 04, 2013, 06:11:32 PM
They are easy to mash on. Certainly not ruling anything out, just think it odd that the water pump, thermostat and radiator were functioning fine prior to changing coolant and now one of those parts is not functioning.
Title: Re: Coolant drain and refill
Post by: sftibbs on April 05, 2013, 02:32:44 AM
Well just for fun I put in another new thermostat and everything is working as it should be. Amazing but true...thanks again.
Title: Re: Coolant drain and refill
Post by: Mike S on April 05, 2013, 03:04:18 AM
 That's good news it is working. Are you able to push the poppet away from its seat?
I usually will work the poppet when new because I have seen a few that stick pretty tight until worked.
Also, putting it in a pot of water on the stove is a good pre-install test (when the wife isn't home)  ;)

Thanks for the follow up. It's always good to hear what the fix is for problems.
Mike
Title: Re: Coolant drain and refill
Post by: sftibbs on April 05, 2013, 03:12:12 AM
Good question. I did take the time to test the new one with the boiling water method and it did open up. I had to test the one I took out just to see and it failed to open.
Title: Re: Coolant drain and refill
Post by: tmodel66 on April 05, 2013, 04:26:13 AM
Glad you caught it instead of taking off and ruining a motor.
Title: Re: Coolant drain and refill
Post by: 69Z28-RS on April 05, 2013, 04:40:14 AM
Just curious:  what was the brand of the 'new one that did NOT work'??
shows to go ya..   sometimes the new stuff is bad too....
Title: Re: Coolant drain and refill
Post by: sftibbs on April 05, 2013, 03:07:51 PM
Superstat from Napa Auto Parts AND made in the USA! Napa had no problem with the exchange...just one of those things.