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what do you mean AFTER EVACUATING BOOSTER and which LEVEL is it? could you be more specific and easier for me to understand, I'm not too mechanically inclined with the lingos, Sorry and Thank youAfter evacuating booster (key out/off, pump pedal 40 times) to check level, how long did it take charged. 35 to 40 sec would be perfect.
To check brake fluid level there is a procedure which is done with vehicle on level ground. If you look on top of the reservoir, you'll see this procedure written out.what do you mean AFTER EVACUATING BOOSTER and which LEVEL is it? could you be more specific and easier for me to understand, I'm not too mechanically inclined with the lingos, Sorry and Thank you
WOW! Thank you for Illustrating and having the time to explain it, I have a clearer and better understanding of what to do and HOPEFULLY, zero in to the problem. Happy New Year and Live Long and PROSPER!To check brake fluid level there is a procedure which is done with vehicle on level ground. If you look on top of the reservoir, you'll see this procedure written out.
What it states is with key off/out pump brake pedal 40 times. This evacuates booster pump/canister which is holding brake fluid, into the reservoir. Once booster is evacuated, check to see that brake fluid is at the max line (not over or under).
As you can see fluid is at top max line, which is maximum it should be at. The max line is about 4mm wide, it can at bottom of max line.
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Now that we've followed procedure to check level, we time how long it takes booster pump/canister to fill back up. Simple turn key to ON and time how long booster pump runs. You''l see brake fluid in reservoir drawing down. I do not starter engine for this test, as it makes hearing the pump more difficult. It should take 30 to 40 seconds for a health system until booster pump stops. More time could indicate system has air, so bleed and re test. If all air bleed out and still running longer or short, something needs fixing.
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You can see booster pump drawn down the fluid level to halfway between max & min lines. Had this reservoir been low after level check (evacuating booster) it may have drop below min line as booster canister filled. Below min line will activate alarm.
Keep in mind that brake fluid level is based on new brake pads & rotors. That level will drop a little bit as pads & rotors wear. So it is ok to be a little below max. If topped when pads & rotors are worn, installing new pads & rotors may put over max line. Running over max is not advisable.
You should never have to add fluid, unless flushing. Needing to add may indicate leak.
Thank you @uHu that means a lot, especially coming from you!2001LC, you are really doing a fantastic job on this forum. Your posts help to bring us to a very high level as a technical LC forum. Your standards, presicion, thoroughness, willingness to help, are high above what most of us manage.
Sorry, but someone had to say it.
Good luck to the OP. It will be interesting to see the cause of the problem, and the solution.
Your welcome again. Just hope it helps! Keep in mind above is only start of evaluating brake system.You should run for public office, hardly do you see people extend kindness, share passion...thanks again Bro!
You can just suck it out or reservoir, A very thin hose is needed to get past stop under cap. A better way is bleeding off some by depressed brake pedal, key on (runs booster pump) than bleed a rear bleeder. I say rear because you can drain as much as you want without pumping pedal. Just don't empty revoir. For fronts you'll need a helper to pump pedal and hold, only getting a little at a time. By bleeding off a little rather than sucking out of reservoir it gets some of the nastiest old fluid out of calipers. Caliper is where heat is generated boiling the brake fluid, and attacking the most moisture.If the fluid is above the max line, can suck some out the reservoir?
Hi i am having trouble with abs light on amazon 4.2, came up with abs pump motor replaced with brand new genuine. still no good lol, when you start the vehicle after about 10 minutes the abs light comes on ???? any help guys as i am strugglingWell known issue. The booster pump has probably failed. Do a search to find all the threads detailing it.