Over filling brake fluid
Discussion
227bhp said:
Yes it's well known for MPG to suffer when there is too much brake fluid in.
Ouch!What I was getting at would too much brake fluid hold the pads onto the discs lightly. The only stupid question is the one you dont ask
However thanks for the demonstration of your superior wit and intellect
smileymikey said:
227bhp said:
Yes it's well known for MPG to suffer when there is too much brake fluid in.
Ouch!What I was getting at would too much brake fluid hold the pads onto the discs lightly. The only stupid question is the one you dont ask
However thanks for the demonstration of your superior wit and intellect
That isn't how brake systems work, i'm sure a quick google will throw up some diagrams for you to look at to understand it better, but the reservoir is just that (google the term) it is just a place to store fluid until it is needed.
Edited by 227bhp on Tuesday 12th January 06:22
227bhp said:
Jazoli said:
It will be fine, as the level will drop as the pads wear anyway, can't comment on the mpg, probably the garage mechanic redlining it for a few miles..............
You're assuming the pads are new. If they are worn and they put news ones in later it will push fluid out.Jazoli said:
227bhp said:
Jazoli said:
It will be fine, as the level will drop as the pads wear anyway, can't comment on the mpg, probably the garage mechanic redlining it for a few miles..............
You're assuming the pads are new. If they are worn and they put news ones in later it will push fluid out.A bit off topic but the rear brake on Aprilia Milles will drag badly if the master cylinder is overfilled, as the fluid is heated by the engine/exhaust it expands and applies the brake, sometimes to the point of preventing the wheel from turning.
I see no reason why this could not happen to a car if the reservoir was overfilled to the point no air gap remained.
I see no reason why this could not happen to a car if the reservoir was overfilled to the point no air gap remained.
I'd just take a little out. Turkey baster is a good call. last time I did my pads I just sucked a bit out with a some clear plastic tubing, being careful to stop sucking before it reached my lips.
You could also enlist the help of wife/gf. There're good at this sort of thing, like to get involved and feel useful
You could also enlist the help of wife/gf. There're good at this sort of thing, like to get involved and feel useful
Edited by PositronicRay on Tuesday 12th January 07:40
227bhp said:
That's ok, i'll send you my invoice.
That isn't how brake systems work, i'm sure a quick google will throw up some diagrams for you to look at to understand it better, but the reservoir is just that (google the term) it is just a place to store fluid until it is needed.
Much to the OP's credit this is exactly how brake systems work. The brake fluid circuit, including the reservoir should be sealed from the atmosphere to prevent moisture ingress into the fluid.That isn't how brake systems work, i'm sure a quick google will throw up some diagrams for you to look at to understand it better, but the reservoir is just that (google the term) it is just a place to store fluid until it is needed.
If considerably over-filled, then any expansion of the fluid (due to temperature) could pressurise the system and result in the brakes dragging.
Simple answer has been given let's not turn this into another ,I'm right, your right, you'll die, it'll explode, thread.
Simple, your mechanic over filled, by how much we are not sure as you don't say.
If it bothers you which I assume it does or you would not have posted, then remove some so the level of the fluid is at the correct level.
I like fluids at max some go for middle of the range.
Most importantly, check all your fluid levels ( in the car for those with wit) regularly
Simple, your mechanic over filled, by how much we are not sure as you don't say.
If it bothers you which I assume it does or you would not have posted, then remove some so the level of the fluid is at the correct level.
I like fluids at max some go for middle of the range.
Most importantly, check all your fluid levels ( in the car for those with wit) regularly
PaulKemp said:
Simple answer has been given let's not turn this into another ,I'm right, your right, you'll die, it'll explode, thread.
Simple, your mechanic over filled, by how much we are not sure as you don't say.
If it bothers you which I assume it does or you would not have posted, then remove some so the level of the fluid is at the correct level.
I like fluids at max some go for middle of the range.
Most importantly, check all your fluid levels ( in the car for those with wit) regularly
Is the right answer (apart from lack of turkey baster, which is a good idea). It would have helped greatly if we were told how much it was overfilled by.Simple, your mechanic over filled, by how much we are not sure as you don't say.
If it bothers you which I assume it does or you would not have posted, then remove some so the level of the fluid is at the correct level.
I like fluids at max some go for middle of the range.
Most importantly, check all your fluid levels ( in the car for those with wit) regularly
Mr2Mike said:
227bhp said:
That's ok, i'll send you my invoice.
That isn't how brake systems work, i'm sure a quick google will throw up some diagrams for you to look at to understand it better, but the reservoir is just that (google the term) it is just a place to store fluid until it is needed.
Much to the OP's credit this is exactly how brake systems work. The brake fluid circuit, including the reservoir should be sealed from the atmosphere to prevent moisture ingress into the fluid.That isn't how brake systems work, i'm sure a quick google will throw up some diagrams for you to look at to understand it better, but the reservoir is just that (google the term) it is just a place to store fluid until it is needed.
If considerably over-filled, then any expansion of the fluid (due to temperature) could pressurise the system and result in the brakes dragging.
If you think that the reservoir is sealed so well from the atmosphere then leave the cap on, crack open a caliper bleed nipple and see if brake fluid runs out.
It will. This will tell you quite a lot and you can't argue with basic physics.
Mr2Mike said:
227bhp said:
That's ok, i'll send you my invoice.
That isn't how brake systems work, i'm sure a quick google will throw up some diagrams for you to look at to understand it better, but the reservoir is just that (google the term) it is just a place to store fluid until it is needed.
Much to the OP's credit this is exactly how brake systems work. The brake fluid circuit, including the reservoir should be sealed from the atmosphere to prevent moisture ingress into the fluid.That isn't how brake systems work, i'm sure a quick google will throw up some diagrams for you to look at to understand it better, but the reservoir is just that (google the term) it is just a place to store fluid until it is needed.
If considerably over-filled, then any expansion of the fluid (due to temperature) could pressurise the system and result in the brakes dragging.
In fact clogged brake res caps are an issue on some cars where when hot the brakes stick on, i (or any other mechanic) then clean the breather out In the cap) and cure the issue, transit Mk3/4/5 sufferd from this a fair bit.
S0 What said:
If the master cylinder res was sealed (which ni on all are not)
What does that mean? I'm not taking the piss, I have no idea.S0 What said:
there would be a vacume created as the pads wore and heating the res would create preasure in the master and force the brakes on, i cant think of many (any?) sealed brake res ??
To seal a brake reservoir a flexible diaphragm is used between the fluid and air to prevent moisture ingress, but allow the level of the fluid to drop. Not all reservoirs have them but some do, in which case it should be obvious that overfilling could cause pressurisation.This Dummies Guide seems rather apt for this thread. See the second pic.
oookay
The fluid is filled well above the max level to the base of the screw neck filler spout. It was this that caused me to look in the first place as I couldn't see the level between the min and max marks and the res appeared empty. They serviced the car four weeks ago and Ive covered five thousand miles since ( so I'm guessing it was a fair bit higher, and pad wear has dropped the level) I can hear that the pads are brushing against the disks lightly). I made the comment about mpg as I had noticed the drop since the service, basing fuel consumption on forty thousand miles in the previous ten months.
The fluid is filled well above the max level to the base of the screw neck filler spout. It was this that caused me to look in the first place as I couldn't see the level between the min and max marks and the res appeared empty. They serviced the car four weeks ago and Ive covered five thousand miles since ( so I'm guessing it was a fair bit higher, and pad wear has dropped the level) I can hear that the pads are brushing against the disks lightly). I made the comment about mpg as I had noticed the drop since the service, basing fuel consumption on forty thousand miles in the previous ten months.
Due to my age my brain functions are limited and I have surrendered to the fact that I now need supervision whenever I tackle a technical issue. I recently repaired the brakes on my 2005 Chrysler town and country by replacing the rotor and brake pads on the front wheels. I submit the following for your consideration. By depressing the pistons in the front calipers I pushed the brake fluid out of the pistons to the point of overflowing the brake fluid reservoir. When the repair was completed I drove the said vehicle for a few miles and heated up the fluid causing the reservoir to slightly pressurize and not allowing the piston to fully retract there for causing the brake system to heat up even more to the point there was smoke coming from the front rotors and brake pads. When I got home I checked the reservoir level by removing the lid and therefore relieving the Pressure. Next morning I drove said vehicle and the problem seem to have disappeared. Conclusion, I should remove some of the fluid from the reservoir returning the level to the high level mark and therefore giving the fluid the room to expand on future tempeture expansion.
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