maintance: breaks and rotors... gas tank pressure?
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maintance: breaks and rotors... gas tank pressure?
so i have ~90% pad on 3 wheels (both rear and passenger) and 65+% pad on the driver wheel paper work says all 4 were replaced at the same time a year ago and both callipers and discs were replaced (note below)...
My break fluid is completly black and the pedal is sponge... (i drive the car 10 miles a day 4 days a week hard to really notice these things)
there is no shake or wobble in the front end during breaking (applying or relieving pressure) how ever upon breaking past 5mph there is a slight pull to the driver side which i attribute to the extra wear?
so before i go and get crazy and replace the rotors/caliper's pads on the front is there any thing else i should be looking at that might cause this exaggeration of wear on just the front driver?
i know i have to bleed all the lines and flush the system with fresh fluid the cars 20 years old and i have no paper work showing replacement of the lines...
so as of right now im looking at rotor, caliper, hub,... i guess only the caliper and rotor would effect pad wear?
My break fluid is completly black and the pedal is sponge... (i drive the car 10 miles a day 4 days a week hard to really notice these things)
there is no shake or wobble in the front end during breaking (applying or relieving pressure) how ever upon breaking past 5mph there is a slight pull to the driver side which i attribute to the extra wear?
so before i go and get crazy and replace the rotors/caliper's pads on the front is there any thing else i should be looking at that might cause this exaggeration of wear on just the front driver?
i know i have to bleed all the lines and flush the system with fresh fluid the cars 20 years old and i have no paper work showing replacement of the lines...
so as of right now im looking at rotor, caliper, hub,... i guess only the caliper and rotor would effect pad wear?
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I would say the pad wear on the driver side is from a sticky caliper, which would explain the pull to the driver side as well. Also I would attribute the shaking from end to the caliper as well. When your brakes get really hot(and they will with a sticky caliper) and then you come to a stop with you foot on the brake pedal, or in your case you have no choice since the caliper is resting the pad right against the rotor, it will leave a deposit of pad material on the rotor itself. Over time these deposits build up and create the wobble you feel under braking.
So first step would be to purchase some new good brake fluid, maybe around 1 liter or more for a full bleed. Remove the front calipers like you would for a normal brake job, and compress the pistons(or pads) into the caliper. If the driver side is sticky or frozen, you will notice it is much more difficult to push in, and if you can identify that it is in fact frozen or hard to push in, you will either want a new caliper(you can get cheap re-mans from your local auto store) or you will want to refresh the caliper by removing the piston, using a hone to smooth out the cylinder and get new seals. It may not be a bad idea to get new front pads, and have the rotors turned, but if you are on a budget, you may be able to re-use the pads and do a proper "break in procedure" to remove the wobble. This requires you to make some hard stops from 60mph to 5mph a few times back to back without ever coming to a complete stop, then letting the brakes cool, again without coming to a complete stop. This will heat up the pads and rotors, and remove the pad deposits that were left on the rotor, then allowed to cool down giving you a even pad deposit on the rotor.
And yes you will want to bleed the system regardless, as I feel like you will have to remove a caliper anyway.
Also what's this about a fuel tank pressure? Did you get a check engine light or something?
Thanks,
Rick
So first step would be to purchase some new good brake fluid, maybe around 1 liter or more for a full bleed. Remove the front calipers like you would for a normal brake job, and compress the pistons(or pads) into the caliper. If the driver side is sticky or frozen, you will notice it is much more difficult to push in, and if you can identify that it is in fact frozen or hard to push in, you will either want a new caliper(you can get cheap re-mans from your local auto store) or you will want to refresh the caliper by removing the piston, using a hone to smooth out the cylinder and get new seals. It may not be a bad idea to get new front pads, and have the rotors turned, but if you are on a budget, you may be able to re-use the pads and do a proper "break in procedure" to remove the wobble. This requires you to make some hard stops from 60mph to 5mph a few times back to back without ever coming to a complete stop, then letting the brakes cool, again without coming to a complete stop. This will heat up the pads and rotors, and remove the pad deposits that were left on the rotor, then allowed to cool down giving you a even pad deposit on the rotor.
And yes you will want to bleed the system regardless, as I feel like you will have to remove a caliper anyway.
Also what's this about a fuel tank pressure? Did you get a check engine light or something?
Thanks,
Rick
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i bought a liter and hade 3 (pints the small topper offers) i will be doing a flush on sunday ~
prestone break fluid in the dot 3 variety... i haven't decided what i want to do yet.... either way all 4 pads up front are being replaced... if i have a sticky piston.... the ls400 calipers and rotors are cheaper... so we shall see... All i know it its looking like a rock auto order... (its $40 turned or $35 for new larger)
prestone break fluid in the dot 3 variety... i haven't decided what i want to do yet.... either way all 4 pads up front are being replaced... if i have a sticky piston.... the ls400 calipers and rotors are cheaper... so we shall see... All i know it its looking like a rock auto order... (its $40 turned or $35 for new larger)
Last edited by jgilk1; 09-26-12 at 01:03 AM.
#4
You never did get to the "gas tank pressure" part of your post but if yours is building up I'll bet you have the same problem I do -- a clogged vent line. My car's tank vent is blocked both in the line inside the tank and the line that leads from there to the front of the car. I mean it's solid, where hooking up a shop's air compressor doesn't budge anything.
I suppose I'll have to replace the tank to permanently fix the problem. Right now I'm considering some sort of rigged fix with a T from the filler vent line. I don't like rubber fuel hose inside the trunk though so I'm considering other options. Anything to get the excess pressure out of the tank is good. Others have posted pics of expanded & bowed tanks from all the pressure, not to mention what it does to the fuel pressure at the engine.
I suppose I'll have to replace the tank to permanently fix the problem. Right now I'm considering some sort of rigged fix with a T from the filler vent line. I don't like rubber fuel hose inside the trunk though so I'm considering other options. Anything to get the excess pressure out of the tank is good. Others have posted pics of expanded & bowed tanks from all the pressure, not to mention what it does to the fuel pressure at the engine.
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oh yeah im getting a bit of back pressure in the tank.. that seems to relieve its self when i unscrew the gas cap... is there a vapor can in the sc400 that is suppose to do this at high vacuum or what is the standard method in which this is to vent? (its only about 2-5 psi so im not excessively worried)
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