Flushing the radiator
Thread Starter
Instructor
Joined: Nov 2017
Posts: 247
Likes: 43
From: Virginia Beach Virginia
Flushing the radiator
Do you guys use any chemicals with the distilled water when flushing your radiators?
Also, is there any negative side to mixing coolant (Prestone with Peak + Stop Leak)?
Also, is there any negative side to mixing coolant (Prestone with Peak + Stop Leak)?
Last edited by VirginiaVette78; Dec 16, 2017 at 04:34 PM. Reason: im an idiot..
Melting Slicks
Joined: Jul 2010
Posts: 3,176
Likes: 633
From: perth western australia
you have to have a filler cap on it somewhere in the system ?
I find those stop leak type additives rarely work for long , at best they hold for a few running hours then you back to square one .
I find those stop leak type additives rarely work for long , at best they hold for a few running hours then you back to square one .
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
If you want to flush the radiator, use 'radiator flush'; if you want to clean the radiator, use 'radiator CLEANER'. Two entirely different products. The cleaner will remove any built up lime deposits in the radiator; radiator flush will not.
Last edited by 7T1vette; Dec 16, 2017 at 04:53 PM.
Thread Starter
Instructor
Joined: Nov 2017
Posts: 247
Likes: 43
From: Virginia Beach Virginia
I do have a filler cap. I just now put my additive in and currently waiting for it to cool off. Strangely, when I drained the rad. And put distilled water in with my flush mix, it didn't even take 2 gallons total... that seemed off to me. But if that's correct, I'm going to just use my Prestone and not any of the stop leak. Thanks for the knowledge!
Thread Starter
Instructor
Joined: Nov 2017
Posts: 247
Likes: 43
From: Virginia Beach Virginia
NEW ISSUE!
Flushed the radiator - new coolant is in. everything was going great. Once the new fluid was in, I started the car, let it run for a minute, went to turn on the heat (which has not worked at all since I bought the car in early Nov.), and it started to act like it was starving of fuel. Went to check it out, saw nothing obvious, heard it about to stall so I quickly turned the heat back off on it and it started to sound normal again.. a few seconds later it stalled. Started it right back up, then stalled instantly, repeated that one more time. I don't want to keep trying to start it for fear of flooding.
Thoughts?
Flushed the radiator - new coolant is in. everything was going great. Once the new fluid was in, I started the car, let it run for a minute, went to turn on the heat (which has not worked at all since I bought the car in early Nov.), and it started to act like it was starving of fuel. Went to check it out, saw nothing obvious, heard it about to stall so I quickly turned the heat back off on it and it started to sound normal again.. a few seconds later it stalled. Started it right back up, then stalled instantly, repeated that one more time. I don't want to keep trying to start it for fear of flooding.
Thoughts?
Le Mans Master
Joined: Dec 2006
Posts: 8,837
Likes: 1,028
NEW ISSUE!
Flushed the radiator - new coolant is in. everything was going great. Once the new fluid was in, I started the car, let it run for a minute, went to turn on the heat (which has not worked at all since I bought the car in early Nov.), and it started to act like it was starving of fuel. Went to check it out, saw nothing obvious, heard it about to stall so I quickly turned the heat back off on it and it started to sound normal again.. a few seconds later it stalled. Started it right back up, then stalled instantly, repeated that one more time. I don't want to keep trying to start it for fear of flooding.
Thoughts?
Flushed the radiator - new coolant is in. everything was going great. Once the new fluid was in, I started the car, let it run for a minute, went to turn on the heat (which has not worked at all since I bought the car in early Nov.), and it started to act like it was starving of fuel. Went to check it out, saw nothing obvious, heard it about to stall so I quickly turned the heat back off on it and it started to sound normal again.. a few seconds later it stalled. Started it right back up, then stalled instantly, repeated that one more time. I don't want to keep trying to start it for fear of flooding.
Thoughts?
Le Mans Master
Joined: Dec 2006
Posts: 8,837
Likes: 1,028
For those of you that remember the old Prestone coolant flush, the main ingredient is Oxallyc acid. You can still buy this as "wood bleach."
I forget what you can now use for the "nuetralizer."
I would never waste distilled water for a flush. It won't be in there long enough to do any harm.
As for radiators, rodding them out is best.
I forget what you can now use for the "nuetralizer."
I would never waste distilled water for a flush. It won't be in there long enough to do any harm.
As for radiators, rodding them out is best.
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Thread Starter
Instructor
Joined: Nov 2017
Posts: 247
Likes: 43
From: Virginia Beach Virginia
Does that automatically make the vacuum leak one of the hoses connected to the heater valve/doors? or can it be any of the hoses? because my headlights also wont go UP, but they do go DOWN.
Le Mans Master
Joined: Dec 2006
Posts: 8,837
Likes: 1,028
I "assume" one of your vacuum leaks is the rotary selector, or down stream from there. If this car is new to you, changing ALL the vacuum hoses, stem to stern should be high on your list.
Thread Starter
Instructor
Joined: Nov 2017
Posts: 247
Likes: 43
From: Virginia Beach Virginia
Is this most of what I should get?
https://www.ecklerscorvette.com/corv...1977-1979.html
https://www.ecklerscorvette.com/corv...1973-1979.html
https://www.ecklerscorvette.com/corv...1968-1982.html
https://www.ecklerscorvette.com/corv...1968-1982.html
Melting Slicks
Joined: Jul 2010
Posts: 3,176
Likes: 633
From: perth western australia
If the hoses look good ,there are things you can try to get it going .
Cut a little bit of the ends of each hose to get rid of the stretched part , that will give you a "fresher " piece that has more chance of not leaking .
BUT if there's any cracks of any size in them ,it up to you if you want to continue that way , buying new ones will eliminate any chance of multiple tiny leaks in each hose that will drive you insane trying to chase them . New hoses don't cost much so personally I would just get some and be done . Leave the old ones on and replace one at a time .
Now your car was running ok until you switched the heater on , so that part has a leak , the kits have all hoses so you will need to open up the console and expose the controls to get at them (obviously ! )
So you might have a leaky rotary selector on your heater control in the console as Bird said.
and bad seals on the headlight actuator shafts . This is because vacuum pulls them shut ok so the main diaphragm (that the shaft is attached to is good , but when you switch to open vacuum comes in from the front to pull that main diaphragm forward and now the seals around the shaft are probably knackered so you get no pull . They sell kits to replace but a test to ensure that is the problem is to lie down in front of the car and reach up and unplug both vac lines coming into one actuator , now you should be able to lift up and down the unit by hand (watch your fingers don't get pinched ) Now when your doing this you should hear a rush of air entering and exiting the little ports you pulled the hoses off as the diaphragm is moving . Now get the light up about half way with one hand and then plug the forward hole with a fingertip so it seals tight , NOW try to move the light each way and see what happens , it shouldn't move (if those seals are good ) if it moves its because air is getting in and there's only one place it can , a worn seal.
do the same test on the back port will test the main diaphragm , if they move with that port blocked the main diaphragm is shot and unfortunately you throw the thing in the bin , but you said they go down so both should be good .
Hope it helps .
Cut a little bit of the ends of each hose to get rid of the stretched part , that will give you a "fresher " piece that has more chance of not leaking .
BUT if there's any cracks of any size in them ,it up to you if you want to continue that way , buying new ones will eliminate any chance of multiple tiny leaks in each hose that will drive you insane trying to chase them . New hoses don't cost much so personally I would just get some and be done . Leave the old ones on and replace one at a time .
Now your car was running ok until you switched the heater on , so that part has a leak , the kits have all hoses so you will need to open up the console and expose the controls to get at them (obviously ! )
So you might have a leaky rotary selector on your heater control in the console as Bird said.
and bad seals on the headlight actuator shafts . This is because vacuum pulls them shut ok so the main diaphragm (that the shaft is attached to is good , but when you switch to open vacuum comes in from the front to pull that main diaphragm forward and now the seals around the shaft are probably knackered so you get no pull . They sell kits to replace but a test to ensure that is the problem is to lie down in front of the car and reach up and unplug both vac lines coming into one actuator , now you should be able to lift up and down the unit by hand (watch your fingers don't get pinched ) Now when your doing this you should hear a rush of air entering and exiting the little ports you pulled the hoses off as the diaphragm is moving . Now get the light up about half way with one hand and then plug the forward hole with a fingertip so it seals tight , NOW try to move the light each way and see what happens , it shouldn't move (if those seals are good ) if it moves its because air is getting in and there's only one place it can , a worn seal.
do the same test on the back port will test the main diaphragm , if they move with that port blocked the main diaphragm is shot and unfortunately you throw the thing in the bin , but you said they go down so both should be good .
Hope it helps .
Melting Slicks
Joined: Jul 2010
Posts: 3,176
Likes: 633
From: perth western australia
might be worth it to get this with the hoses ,
https://www.ecklerscorvette.com/corv...1968-1982.html
https://www.ecklerscorvette.com/corv...1968-1982.html
Thread Starter
Instructor
Joined: Nov 2017
Posts: 247
Likes: 43
From: Virginia Beach Virginia
If the hoses look good ,there are things you can try to get it going .
Cut a little bit of the ends of each hose to get rid of the stretched part , that will give you a "fresher " piece that has more chance of not leaking .
BUT if there's any cracks of any size in them ,it up to you if you want to continue that way , buying new ones will eliminate any chance of multiple tiny leaks in each hose that will drive you insane trying to chase them . New hoses don't cost much so personally I would just get some and be done . Leave the old ones on and replace one at a time .
Now your car was running ok until you switched the heater on , so that part has a leak , the kits have all hoses so you will need to open up the console and expose the controls to get at them (obviously ! )
So you might have a leaky rotary selector on your heater control in the console as Bird said.
and bad seals on the headlight actuator shafts . This is because vacuum pulls them shut ok so the main diaphragm (that the shaft is attached to is good , but when you switch to open vacuum comes in from the front to pull that main diaphragm forward and now the seals around the shaft are probably knackered so you get no pull . They sell kits to replace but a test to ensure that is the problem is to lie down in front of the car and reach up and unplug both vac lines coming into one actuator , now you should be able to lift up and down the unit by hand (watch your fingers don't get pinched ) Now when your doing this you should hear a rush of air entering and exiting the little ports you pulled the hoses off as the diaphragm is moving . Now get the light up about half way with one hand and then plug the forward hole with a fingertip so it seals tight , NOW try to move the light each way and see what happens , it shouldn't move (if those seals are good ) if it moves its because air is getting in and there's only one place it can , a worn seal.
do the same test on the back port will test the main diaphragm , if they move with that port blocked the main diaphragm is shot and unfortunately you throw the thing in the bin , but you said they go down so both should be good .
Hope it helps .
Cut a little bit of the ends of each hose to get rid of the stretched part , that will give you a "fresher " piece that has more chance of not leaking .
BUT if there's any cracks of any size in them ,it up to you if you want to continue that way , buying new ones will eliminate any chance of multiple tiny leaks in each hose that will drive you insane trying to chase them . New hoses don't cost much so personally I would just get some and be done . Leave the old ones on and replace one at a time .
Now your car was running ok until you switched the heater on , so that part has a leak , the kits have all hoses so you will need to open up the console and expose the controls to get at them (obviously ! )
So you might have a leaky rotary selector on your heater control in the console as Bird said.
and bad seals on the headlight actuator shafts . This is because vacuum pulls them shut ok so the main diaphragm (that the shaft is attached to is good , but when you switch to open vacuum comes in from the front to pull that main diaphragm forward and now the seals around the shaft are probably knackered so you get no pull . They sell kits to replace but a test to ensure that is the problem is to lie down in front of the car and reach up and unplug both vac lines coming into one actuator , now you should be able to lift up and down the unit by hand (watch your fingers don't get pinched ) Now when your doing this you should hear a rush of air entering and exiting the little ports you pulled the hoses off as the diaphragm is moving . Now get the light up about half way with one hand and then plug the forward hole with a fingertip so it seals tight , NOW try to move the light each way and see what happens , it shouldn't move (if those seals are good ) if it moves its because air is getting in and there's only one place it can , a worn seal.
do the same test on the back port will test the main diaphragm , if they move with that port blocked the main diaphragm is shot and unfortunately you throw the thing in the bin , but you said they go down so both should be good .
Hope it helps .
might be worth it to get this with the hoses ,
https://www.ecklerscorvette.com/corv...1968-1982.html
https://www.ecklerscorvette.com/corv...1968-1982.html
Melting Slicks
Joined: Jul 2010
Posts: 3,176
Likes: 633
From: perth western australia
wow, incredibly detailed reply! Thank you. I will give that a shot once the sun comes up tomorrow! I'm 99% sure I'm just going to buy the new hoses, but your reply has made me curious anyway so why not get in there and learn something, right? It sounds like you are on board with big2birds theory that the stalling is due to the vacuum line. So my question is now- if it ran fine before I turned the heater on, and then went back to sounding normal after I turned it off, shouldn't it start now that I have "shut off" that vacuum line?
Last edited by bazza77; Dec 17, 2017 at 12:07 AM.
Race Director
Joined: Jul 2015
Posts: 13,082
Likes: 3,399
From: SW Florida.
first close off the vacuum going in to the car and get car running and idling. now you know if the vac leak caused that issue. then go back to chasing down that vacuum leak. the headlights are a fairly big vacuum system. they will cause a big leak. general rule of thumb: if you do something and something else goes wrong, YOU JUST CAUSED IT! but, 35 to 50 year old cars will come up with exceptions to that rule with great regularity.
Thread Starter
Instructor
Joined: Nov 2017
Posts: 247
Likes: 43
From: Virginia Beach Virginia
first close off the vacuum going in to the car and get car running and idling. now you know if the vac leak caused that issue. then go back to chasing down that vacuum leak. the headlights are a fairly big vacuum system. they will cause a big leak. general rule of thumb: if you do something and something else goes wrong, YOU JUST CAUSED IT! but, 35 to 50 year old cars will come up with exceptions to that rule with great regularity.
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,754
From: Charlotte NC
I actually did not even know that. Thank you. I'm going to just assume the radiator needs cleaned since the PO didn't take care of this car in the slightest. Thanks for the tip!
I do have a filler cap. I just now put my additive in and currently waiting for it to cool off. Strangely, when I drained the rad. And put distilled water in with my flush mix, it didn't even take 2 gallons total... that seemed off to me. But if that's correct, I'm going to just use my Prestone and not any of the stop leak. Thanks for the knowledge!
I do have a filler cap. I just now put my additive in and currently waiting for it to cool off. Strangely, when I drained the rad. And put distilled water in with my flush mix, it didn't even take 2 gallons total... that seemed off to me. But if that's correct, I'm going to just use my Prestone and not any of the stop leak. Thanks for the knowledge!
Currently your engine block is holding a mix of old coolant, and whatever you have added to it. Draining the engine block will yield about 2 gallons of liquid. Because when you drain the radiator...the coolant mix that is in the engine block will only drain out to the level of the bottom of the holes in the block where the water pump attaches.
DUB
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,754
From: Charlotte NC
I agree...the normal culprit is the vacuum switch that is attached to your selector switch on your HVAC control. major vacuum leaks at this switch are a problem...BUT...
there also is a vacuum switch that is mounted on top of your heater box that is quite important also and must be in good condition.
The switch mounted on top of your heater box is what is controlling the function of your hot water shut off valve. The rotary switch only controls the inner vacuum pods to move the doors where they are being requested to move to.
You really do not want to pinch the hoses for your HVAc vacuum system. This can cause for more damage.
FIND the very small black hose that is coming out of the grommet on the passenger side of the fire wall...kinda behind the valve cover area and follow it over towards your master cylinder and you will more than likely find where it is attached to the main vacuum hose coming off your intake vacuum fitting.
Knowing where it is now attached allows you do check it out if needed.
I would crank the engine and remove the small vacuum hose attached to your hot water shut off valve and see if there is any vacuum coming to is when I am requesting HEAT.
DUB
there also is a vacuum switch that is mounted on top of your heater box that is quite important also and must be in good condition.
The switch mounted on top of your heater box is what is controlling the function of your hot water shut off valve. The rotary switch only controls the inner vacuum pods to move the doors where they are being requested to move to.
You really do not want to pinch the hoses for your HVAc vacuum system. This can cause for more damage.
FIND the very small black hose that is coming out of the grommet on the passenger side of the fire wall...kinda behind the valve cover area and follow it over towards your master cylinder and you will more than likely find where it is attached to the main vacuum hose coming off your intake vacuum fitting.
Knowing where it is now attached allows you do check it out if needed.
I would crank the engine and remove the small vacuum hose attached to your hot water shut off valve and see if there is any vacuum coming to is when I am requesting HEAT.
DUB