Proportioning box bleeding?
Proportioning box bleeding? I've taken apart my entire brake system and am finallly able to put it back together and bleed it. I've heard or been told their's a special way to bleed the proportioning box yet I can't find any info on it! Whats the deal?
When air gets into the abs/metering block that doesn't get moved out by normal bleeding, you need a higher end computer(tech2, genisys, modis, etc). You have to send a command to the abs unit to do an automated bleed function that forces air out of the block into the lines after it.
In my experience, it's kind of a chance thing. It's very possible that just going through the normal bleed you'll be fine. About six months ago I did a brake upgrade on a 98 chevy truck, and I had to go though the computer to properly bleed it. I did a disk brake conversion and replaced the metering valve on the abs block on my 97 tahoe that I don't drive every day. I let it sit for a few weeks and all the air came up to the resovoir by itself and I never bothered bleeding it. In worst case, go to a local dealership and talk to one of the mechanics. Offer them $20 to come by your place after work with a computer. I've never let the block go dry in my fbod, so I really don't know exactly how it's going to go for you. Oh, and after all my babbling, to answer your question, just rely on how your pedal feels, it will tell you if your brakes are working or not.
