C2 Bleeding Frustration STILL.

[Ralph B.]

Follow up to my previous post with no success bleeding rear brakes after replacing the rear cross over line.

I removed the MC yesterday and went through the bench bleeding proceedure thouroughly removing all bubbles, reinstalled MC and repeated
the caliper bleeding process using all the best tehniques recommended with no possitive results at all, (status quo).

I again removed M/C and re-bled. Then I re-directed the bleed line into a pan to to observe the flow of fluid when piston is depressed.

My question is: shouldn't this shoot out an impressive shot of fluid everytime I depress the cylinder? ---------- All I see is a small shot of fluid that shoots out about an inch on the first stroke then subsequent strokes only yield dribs and drabs in the back port, but the front port shoots a quality amount of fluid at each stroke.

Could the MC be the source of my problem?

Thank you all for help and patients,
Ralph

[Michael W.]

Re: C2 Bleeding Frustration STILL.

My question is: shouldn't this shoot out an impressive shot of fluid everytime I depress the cylinder? ---------- All I see is a small shot of fluid that shoots out about an inch on the first stroke then subsequent strokes only yield dribs and drabs for both front and rear ports.

If the outlet ports are open the atmosphere, air will be sucked in when the piston is released. That might be why little fluid is expelled on subsequent strokes.

[Ralph B.]

Re: C2 Bleeding Frustration STILL.

If the outlet ports are open the atmosphere, air will be sucked in when the piston is released. That might be why little fluid is expelled on subsequent strokes.

Michael,

Correction to my post: apparently the front MC port does indeed expell a good shot of fluid at EVERY manual stroke of the piston, but the rear port only yields "dribs and drabs" which is where I'm having the bleeding problem.

With the MC in the car it appears it's just not pushing any fluid to the rear at all no matter how many times we pump the brake which is exactly what I'm now seeing on the bench.

Is it possible for the MC to only work on the front and not the back, or vice versa? or, if the MC is faulty wouldn't both sides not do it's job?

Ralph.
Thank you!

[Michael W.]

Re: C2 Bleeding Frustration STILL.

It's very possible to have just one side faulty. The two sides are independent in function.

[Gene M.]

Re: C2 Bleeding Frustration STILL.

With out any doubt the m/c is bad. It is typical now days to get rebuilts this way right out of the box. Suggest a top quality m/c from some place like Stainless steel brakes.

About three x the cost of a new Delco (made in china crap) but well worth the elimination of problems.

[Ralph B.]

Re: C2 Bleeding Frustration STILL.

With out any doubt the m/c is bad. It is typical now days to get rebuilts this way right out of the box. Suggest a top quality m/c from some place like Stainless steel brakes.

About three x the cost of a new Delco (made in china crap) but well worth the elimination of problems.

Thank you Gene, yes it's sarting to look like that is the case which is need of rebuild.

I'm no expert but this 66 PB MC appears to be original; P/N 5467084 DELCO MORAINE, has 2 plastic caps, 1/4 lines and a blind boss in the front.

I will give SS brake a call tommorow unless anyone else has any other ideas. I have repeated the bench bleeding process at least 6 times now with the same results (no stream of fluid exiting the rear port) but the front looks fine.

Is there any chance there could be something restricting the exit flow such as piece of dirt on that side? ----- Do you think I should run some kind of solvent and or blow some compressed air through the threaded exit hole ????

Ralph

[Michael W.]

Re: C2 Bleeding Frustration STILL.

Why not disassemble it and look for a defective seal or damaged bore? Nothing to lose at this point.

[Ralph B.]

Re: C2 Bleeding Frustration STILL.

Why not disassemble it and look for a defective seal or damaged bore? Nothing to lose at this point.

Your right Michael and I will give that a try ----- this is all new stuff for me.

Good learning experience though!

Thank you !

[Peter J.]

Re: C2 Bleeding Frustration STILL.

Luke & John at CSSB have the right rebuild kit for your MC, I just got a spare kit for my -66 PB M/C.

[Ralph B.]

Re: C2 Bleeding Frustration STILL.

Luke & John at CSSB have the right rebuild kit for your MC, I just got a spare kit for my -66 PB M/C.

Peter,

As recommended I'm going to disassemble the MC to see what's going on and if the bore looks OK then I will order the kit with them (CSSB) otherwise I will sent it out for rebuild to Apple Hydraulics and be done with it.

After the MC is corrected I was tempted to revert back to conventional fluid which apparently is much easier to bleed, but, that would involve quite a process to do it correctly, so I'll stay with DOT5.

Thank you!
Ralph

[Larry M.]

Re: C2 Bleeding Frustration STILL.

Peter,

As recommended I'm going to disassemble the MC to see what's going on and if the bore looks OK then I will order the kit with them (CSSB) otherwise I will sent it out for rebuild to Apple Hydraulics and be done with it.

After the MC is corrected I was tempted to revert back to conventional fluid which apparently is much easier to bleed, but, that would involve quite a process to do it correctly, so I'll stay with DOT5.

Thank you!
Ralph

Talk to CSSB or Lone Star Caliper about resleeving your master cylinder. Apple Hydraulics has a good reputation, but CSSB or Lone Star may be an even better choice.

CSSB (Dr Vette) did mine many years ago, and it is still going strong. Lone Star also has an exceptional reputation in this area.

Stick with DOT 5......I think you will be happier in the long run.

Larry

[Ralph B.]

Re: C2 Bleeding Frustration STILL.

Talk to CSSB or Lone Star Caliper about resleeving your master cylinder. Apple Hydraulics has a good reputation, but CSSB or Lone Star may be an even better choice.

CSSB (Dr Vette) did mine many years ago, and it is still going strong. Lone Star also has an exceptional reputation in this area.

Stick with DOT 5......I think you wuill be happier in the long run.

Larry

Thank you Larry ----- I need all the advice I can get, and yes I'm sticking with the DOT 5 --------- with the MC out of the car and the RH and LH rear bleeders completly removed, I tried to gravity feeding some DOT 5 through the open rear line at the MC end by rigging up a 1/4 rubber hose and attaching a mini funnel ----- interestingly the fluid would NOT move (drain down) ---------- the only way it would move was to suction it in using a mighty vac at the caliper. I can only assume, if this was DOT3/4 it would have gravity fed itself with little or no problem, apparently this DOT5 is prone to assuming air bubbles which restricts gravity flow? I read somewhere that it's imperative not to shake this stuff around because it tends to formulate bubbles? Another guy recommended heating it up a little which helps ???????? But my main problem right now is the fact that the MC will not push any fluid out the rear port regardless of what fluid I use!

[Larry M.]

Re: C2 Bleeding Frustration STILL.

Ralph:

Are the rear hoses new and/or in good shape. Sometimes they will collapse internally and cause problems. I would check this while the MC is out being repaired/reconditioned.

Larry

[Ralph B.]

Re: C2 Bleeding Frustration STILL.

Ralph:

Are the rear hoses new and/or in good shape. Sometimes they will collapse internally and cause problems. I would check this while the MC is out being repaired/reconditioned.

Larry

Yes the entire system looks like new and in impeccable condition.
Ralph

[Peter J.]

Re: C2 Bleeding Frustration STILL.

Ralph,
I just rebuilt my calipers with "O-rings", replaced my stainless lines with steel, and just added an original correct booster and master cylinder and used Dot -5 again. I used a Motive Products speed bleeder for the first time last night and can tell you I had my brakes bled in twenty minutes. I was astounded how well it worked over the have a buddy push the pedal technique that was all I had ever done in the past.
I highly recommend their product and thank John Hinckley for the heads up on this tool.