Quote:
Why?Originally Posted by roadtalontsi
you going to need a decent amount of pressure, at the shop we run about 30psi.
lesson I learned was that if you don't know what you're doing, don't tell the mechanics, because they'll probably try to get over on you.
as for the pressure, we kept it at 10 psi, because I kept reading that 10-15 would be more than enough.
as for the pressure, we kept it at 10 psi, because I kept reading that 10-15 would be more than enough.
Mort
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I used 10 PSI when I did mine as well and it worked fine. Maybe just a bit slower than if you use more pressure. I don't need to be in that much of a rush. Not working flat rate in a shop.
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Does fluid get forced through the ABS hydraulic unit at the 10psi level?
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^^^^^ not sure, I just know it comes out the other end.
Quote:
Originally Posted by roadtalontsi
going to need a decent amount of pressure, at the shop we run about 30psi.
Quote:
Bump for answer Originally Posted by Jasonoff
Why?
Senior Member
I use the vacuum method. The H Frt vac converter wants air PRESSURE into one fitting. I throttle the input pressure to about 25-30 psi. Vacuum is available at the output side. This side takes a rubber tube routed to a plastic bottle (usually furnished with the pistol grip vac kit). The little bottles have two nipples. The vacuum tube from the output side of the H frt vac unit is attached to one plastic nipple. Another rubber tube is routed from the second plastic nipple on the bottle to the caliper bleed nipple. Do not touch the brake pedal. Open the caliper nipple. Fluid will (slowly) be pulled into the plastic bottle. You must keep emptying the plastic bottle into your used fluid container. This is a slow process so do not attempt it if you are rushed.
Before starting I reduce the fluid in the master reservoir. (optional) Careful not to overdue or you will admit air. I run lots of fluid through the 4 calipers (1-1/2 MB sized bottles). I go around twice to each caliper, pulling through 2-3 plastic bottle worth on the rears and two between the inner and outer fronts. The best catch bottles have a little black o ring. Those trying to do the vacuum method with the hand held gun probably noticed heat buildup from pumping and charlie horse hands. Never worked for me.
Re fluid in the ABS. My reads for those without star access suggested fluid change, then road-actuation of ABS. I do this by finding a benign strip of wet grass and dry blacktop. Brake and feel the ABS work. Then go home and go through the above process.
Before starting I reduce the fluid in the master reservoir. (optional) Careful not to overdue or you will admit air. I run lots of fluid through the 4 calipers (1-1/2 MB sized bottles). I go around twice to each caliper, pulling through 2-3 plastic bottle worth on the rears and two between the inner and outer fronts. The best catch bottles have a little black o ring. Those trying to do the vacuum method with the hand held gun probably noticed heat buildup from pumping and charlie horse hands. Never worked for me.
Re fluid in the ABS. My reads for those without star access suggested fluid change, then road-actuation of ABS. I do this by finding a benign strip of wet grass and dry blacktop. Brake and feel the ABS work. Then go home and go through the above process.
