Bleeding Versus Flushing Between HPDE Days
#1
Racer
Thread Starter
Bleeding Versus Flushing Between HPDE Days
I have a general question / topic on bleeding RBF between close-together HPDE track days.
I don't really understand the bleed process (instead of flushing) as I've always read to avoid exposing the RBF to atmosphere as moisture will be pulled into the fluid, and it seems that would be the case when attaching my Motive Power Bleeder and pushing a small amount out of each corner. Plus, there's the question of opening another can of RBF (ATE SuperBlue) just to top off the reservoir since it *kind of* ruins the new can by opening it and then storing it again, correct?
So, basically I'm asking how people bleed fluid without making the existing fluid worse in the process by adding moisture. Make any sense?
Thanks in advance,
Dan
I don't really understand the bleed process (instead of flushing) as I've always read to avoid exposing the RBF to atmosphere as moisture will be pulled into the fluid, and it seems that would be the case when attaching my Motive Power Bleeder and pushing a small amount out of each corner. Plus, there's the question of opening another can of RBF (ATE SuperBlue) just to top off the reservoir since it *kind of* ruins the new can by opening it and then storing it again, correct?
So, basically I'm asking how people bleed fluid without making the existing fluid worse in the process by adding moisture. Make any sense?
Thanks in advance,
Dan
#2
Le Mans Master
How often are you doing track days?
Once a month, bleed after an event, flush before the first event next year.
Couple times a year - bleed after an event, flush before the first event of the second year.
Always flush every two years - even a street car!
Now if you switched to SRF someone else would need to chime in. The above is what I use with Valvoline syntec and ATE (blue and gold)
Once a month, bleed after an event, flush before the first event next year.
Couple times a year - bleed after an event, flush before the first event of the second year.
Always flush every two years - even a street car!
Now if you switched to SRF someone else would need to chime in. The above is what I use with Valvoline syntec and ATE (blue and gold)
#3
Safety Car
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Brake fluid is definitely hygroscopic (sp?) and will absorb moisture from the air. A complete flush is not necessary after an event and is a waste of money and time. Just bleed each caliper till nice clean fluid comes out and you will be fine. You will be changing the entire system's fluid after 3-4 events doing this type of bleed. Don't worry about what is left in the can - just close the top tight and it will be fine, even from one season to the next.
#4
Racer
Thread Starter
So basically don't worry about the moisture and just push some volume out of each corner, get the reservoir topped back off and store the rest for next time?
I'm doing two events (one day each) this spring -- 6 weeks apart -- and then will do probably two more days this fall. Too hot in DFW area to run much during the summer and I'm too busy (and pushing it with the wife ) to do more days than that per year.
I'm doing two events (one day each) this spring -- 6 weeks apart -- and then will do probably two more days this fall. Too hot in DFW area to run much during the summer and I'm too busy (and pushing it with the wife ) to do more days than that per year.
#5
Drifting
I just attach the motive to the reservoir and pressurize to 15 psi. I DO NOT fill it with fluid, too messy and it doesn't work anyways. Then I bleed the backs, top off the reservoir, repressurize and bleed the fronts. I get about a half of the bottle (the motive hanger bottles they sell) when I'm done. I do the entire thing by myself and it doesn't take long at all.
Jay
Jay
#6
Drifting
Good post CreaseGaurd & others...that's exactly what I'd planned to do with my Motive bleeder, just a quick bleed at all 4 corners, rear brakes first..
#7
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[QUOTE=DannyBoyC6;1580609401]So basically don't worry about the moisture and just push some volume out of each corner, get the reservoir topped back off and store the rest for next time?
Exactly --- Use the Motive in the fashion that Crease posted and you will be fine. Let the addiction begin !!!
Exactly --- Use the Motive in the fashion that Crease posted and you will be fine. Let the addiction begin !!!
#8
Safety Car
How often are you doing track days?
Once a month, bleed after an event, flush before the first event next year.
Couple times a year - bleed after an event, flush before the first event of the second year.
Always flush every two years - even a street car!
Now if you switched to SRF someone else would need to chime in. The above is what I use with Valvoline syntec and ATE (blue and gold)
Once a month, bleed after an event, flush before the first event next year.
Couple times a year - bleed after an event, flush before the first event of the second year.
Always flush every two years - even a street car!
Now if you switched to SRF someone else would need to chime in. The above is what I use with Valvoline syntec and ATE (blue and gold)
#9
Tech Contributor
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I seal the container that has some left over. First I wrap the top in tape and then put the whole thing in a sealed baggy that has as much air removed from it as possible. Not sure whether that slows down the moisture absorption but it does make me feel better.
Bill
Bill
#11
Race Director
I use nitrogen for bleeding personally. I've kept a canister around for 10 years, and it uses such a small amount that it simply gives me piece of mind.
Also, it's not just moisture, it's heat that damages fluid. A quick bleed flushes the burned fluid (even if it hasn't boiled) and keeps the system mostly fresh.
Most brake fluids lose some of their dry rating as soon as you crap that cap open, so it doesn't bother me if it sits in the lines a few months.
Also, it's not just moisture, it's heat that damages fluid. A quick bleed flushes the burned fluid (even if it hasn't boiled) and keeps the system mostly fresh.
Most brake fluids lose some of their dry rating as soon as you crap that cap open, so it doesn't bother me if it sits in the lines a few months.
#12
Racer
Thread Starter
Great information everyone! Greatly appreciated. I will definitely be storing the opened container in a sealed bag -- an easy reassurance.
It's funny that I've never heard of anyone using the Motive power bleeder with fluid in the bleeder unit itself. When I bought it last year, I immediately saw it was better to just fill the reservoir and use the Motive to pressurize the system.
I've only done 3 HPDE days and I'm completely addicted already.
It's funny that I've never heard of anyone using the Motive power bleeder with fluid in the bleeder unit itself. When I bought it last year, I immediately saw it was better to just fill the reservoir and use the Motive to pressurize the system.
I've only done 3 HPDE days and I'm completely addicted already.
#13
Drifting
Great information everyone! Greatly appreciated. I will definitely be storing the opened container in a sealed bag -- an easy reassurance.
It's funny that I've never heard of anyone using the Motive power bleeder with fluid in the bleeder unit itself. When I bought it last year, I immediately saw it was better to just fill the reservoir and use the Motive to pressurize the system.
I've only done 3 HPDE days and I'm completely addicted already.
It's funny that I've never heard of anyone using the Motive power bleeder with fluid in the bleeder unit itself. When I bought it last year, I immediately saw it was better to just fill the reservoir and use the Motive to pressurize the system.
I've only done 3 HPDE days and I'm completely addicted already.
Jay
#14
Racer
Thread Starter
I'm signed up for Eagles Canyon Raceway on May 12th so I'm very much looking forward to the new course. Looks much faster but possibly less challenging from comparing maps.
How about you?
Thanks,
Dan
#15
Drifting
I use nitrogen for bleeding personally. I've kept a canister around for 10 years, and it uses such a small amount that it simply gives me piece of mind.
Also, it's not just moisture, it's heat that damages fluid. A quick bleed flushes the burned fluid (even if it hasn't boiled) and keeps the system mostly fresh.
Most brake fluids lose some of their dry rating as soon as you crap that cap open, so it doesn't bother me if it sits in the lines a few months.
Also, it's not just moisture, it's heat that damages fluid. A quick bleed flushes the burned fluid (even if it hasn't boiled) and keeps the system mostly fresh.
Most brake fluids lose some of their dry rating as soon as you crap that cap open, so it doesn't bother me if it sits in the lines a few months.
Jim
#16
Safety Car
Here is a thread that covers most of what you are asking and then some. The consensus - flush at beginning of season and bleed before every track event. HTH.
http://forums.corvetteforum.com/auto...uring-use.html
http://forums.corvetteforum.com/auto...uring-use.html
#17
Race Director
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I just attach the motive to the reservoir and pressurize to 15 psi. I DO NOT fill it with fluid, too messy and it doesn't work anyways. Then I bleed the backs, top off the reservoir, repressurize and bleed the fronts. I get about a half of the bottle (the motive hanger bottles they sell) when I'm done. I do the entire thing by myself and it doesn't take long at all.
Jay
Jay
For 2003 Z.
#18
Safety Car
Here is a thread that covers most of what you are asking and then some. The consensus - flush at beginning of season and bleed before every track event. HTH.
http://forums.corvetteforum.com/auto...uring-use.html
http://forums.corvetteforum.com/auto...uring-use.html
#19
Former Vendor
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Location: Lewisville TX
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St. Jude Donor '03-'04-'05-'06-'07-'08-'09-'10-'11-'12-'13
This is what we typically will do during most weekend events.
Complete flush of the system at the start of the year and before the first event. While there we will typically do a quick bleed to get fresh fluid into the calipers and top off. Unless a problem comes up during the weekend that is typically all we will do.
In some cases when dealing with a stock C5 or base C6 car and factory brakes you may find yourself bleeding the brakes between each run because there is not enough cooling to the brakes and you are boiling the fluid in the calipers. This will take a little more than a bleed, but not quite a flush as you have to get the burnt fluid out of the calipers and any air trapped as a result.
An endurance setup like the GT2 car, I might not touch all weekend because of the amount of cooling, caliper size, and fluid capacity on the car.
Complete flush of the system at the start of the year and before the first event. While there we will typically do a quick bleed to get fresh fluid into the calipers and top off. Unless a problem comes up during the weekend that is typically all we will do.
In some cases when dealing with a stock C5 or base C6 car and factory brakes you may find yourself bleeding the brakes between each run because there is not enough cooling to the brakes and you are boiling the fluid in the calipers. This will take a little more than a bleed, but not quite a flush as you have to get the burnt fluid out of the calipers and any air trapped as a result.
An endurance setup like the GT2 car, I might not touch all weekend because of the amount of cooling, caliper size, and fluid capacity on the car.
#20
Safety Car
I do a quick bleed at each corner with my Motiv power bleeder before each track weekend. The fluid that comes out always looks fresh. I never do a full flush since the car only sits a few months between events max.