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Well I did some homework here recently as I progressed through replacing most of the brake components on my '77 242. Did all calipers from FCPGroton, (Reman of course as that's all they have), all six flexible lines, taking extensive care to keep everything clean and was easy on the old fittings.
When calipers arrived, the first thing I did was look to see if there were two pin punches or dimples that were side-by-side to insure to me the halves were not mis-matched. I could find NO markes whatsoever. So I took a big gulp, and crossed my fingers....continuing with the job.
I planned to do gravity bleeding as I'd done easily a few years ago. I didn't want to exercise the master cylinder piston to it's full throw in case the far end of it's bore was dirty and I'd merely cause another problem, so I passed on the pump-the-pedal-with-helper system I'd used when I was a kid.
Finished up. All looked good. Everything bled except two bleeders on each of the front calipers. Front, TOP bleeders bled with no problem. So I dug out my, "Easy Bleed," I got years ago, hooked it up to 15 pounds of air from a tire and tried again. This time, the right side did bleed from all three bleeders. Still nothing on the pair of center bleeders for the left side. Tomorrow I'll air up the tire again and try again.
So my questions here are:
1. Do ALL 240 calipers have the dimple/pin punch marks??? (If so I've somehow missed them, or the calipers were bead blasted too much in the reman, distroying the marks)
2. When the reman folks screw up and mis-match caliper halves, are there ALWAYS certain of the bleeders that do not bleed? i.e., is it always the center two as I am noticing, only one, or can it be any combination??
I went through this the last time I did calipers several years ago....when I didn't know about the mis-match history/misery. Those were NAPA. Boy did that push me over the edge !!
At this point, I'd like to pin this down if tomorrow's pressure bleed doesn't work. Oh, BTW, I could get a helper to do the pedal method, but I'm worried if the lines have mis-matched pressures I'd kick that junction block/safety switch to one side and never get it back.
Thanks,
Dennis
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Well, I've had it. I hit the end of my rope tonight. I've got all the calipers bleeding via gravity.....nice slow drip, drip, etc., except......
Left front will do same from top bleeder, but totally dry from the two in the middle. I've tried the gravity method....letting it sit for half an hour. I've used my Easy Bleed, (I think that's it), which uses 20 lb max air pressure from tire, and today a local ex-Volvo mechanic loaned me his $300 vacuum, bleeder that he says he used on all his Volvo work in the past.
Nothing.
I even left 20 pounds standing pressure, (from the tire), on the system at the master cylinder fill cap for 15 minutes and nothing. (OK test for the rest of the system I guess)
So unless someone on this forum can see what I've missed, I'm calling FCP Groton Monday and asking for a replacement. It must be blocked internally.
Getting really disgusting.
Oh, and yes, I've rebuilt master cylinders in the past and have a new one standing by for this '77.
Thanks Everyone,
Dennis
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Try poking a wire into the bleed hole to loosen any obstruction.
One thing I recommend is obtain a spare Master Cylinder and open it up. You'll see it is a simple device and you'll be more inclined to open and clean MCs from then on.
--
1980 245 Canadian B21A with SU carb but electronic ignition and M46 trans in Brampton, Ont.
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So my questions here are:
1. Do ALL 240 calipers have the dimple/pin punch marks??? (If so I've somehow missed them, or the calipers were bead blasted too much in the reman, distroying the marks)
No, just front Girling. Haven't heard of any missing the dimples, but your view of the reman industry isn't likely to be any brighter than mine.
2. When the reman folks screw up and mis-match caliper halves, are there ALWAYS certain of the bleeders that do not bleed? i.e., is it always the center two as I am noticing, only one, or can it be any combination??
No, the mis-matched calipers do eject brake fluid. They don't lose the air. That's because the bleed screw winds up at the bottom, instead of at the top, of the air pocket. You've been there before, so it will come back to you.
If you decide to push the air out with the pedal, be prepared to buy a new master cylinder and repeat the whole mess. Yes, I realize there will be folks who say they know how to do it and succeed. There are a lot of variables, mostly in how long it has been between fluid changes.
My impression is it sounds like you have an obstruction. I think there was a thread a couple years ago where someone bought calipers with one or more plugged bleed bores. We really have to inspect these things they call "remanufactured" and keep in mind how much they could possibly pay the labor and still make a profit from you.
--
Art Benstein near Baltimore
Time may be a great healer, but it's a lousy beautician.
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