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I am having a most depressing experience after having replaced the master cylinder on my wagon. Things are not improving. My self esteem is in the dirt.
To recap. Replaced my non ABS MC with a new one, not rebuilt. Did not bench bleed. Bled all lines using my vacuum bleeder. Focus was on replacing all the fluid. Bled till well past no air being evident. No good. Pedal sunk about 2" before getting firm with no power, and would not pump up. Sunk nearly to the floor with very poor braking with the engine supplying vacuum to the booster. Concluded I still had air in the lines, but puzzled because it wouldn't pump up.
Re-bled everything the conventional way - stick propped against seat - following the Bentley mantra for Volvo brake bleeding. Pedal still no good. Enlisted the wife's aid, with yet another quart in hand. Nada. Got a motive power bleeder and a gallon of DOT 4 and did it all again being very liberal with the brake fluid. Nope.
You can read details of the first half of my tribulations at http://brickboard.com/RWD/index.htm?id=914021&show_all=1.
Also, jacked the rear of the car nearly three feet up then gently rattled the proportioning valves with an air hammer in case they were stuck. Nope. Pumped up the system and let it sit for 10 minutes pressurized, then bled each rear alternately. Repeated for hours, literally. No dice.
Disconnected the rear lines at the differential pressure switch and plugged the ports just to eliminate the rear system. Pedal improved, but only about 50%. Reconnected and re-bled.
Thought a bad MC was unlikely, but ordered another new one just to be sure. Then had a nasty bout of the flu after which (and the bronchitis that followed) I had to get an apartment rent-able. Finally got back to working on the car today.
Bench bled the new MC this time, canted 45° to the left to get the ports at the top because they aren't tangential to the bore. Got every last scrap of air out. Actually, foolishly, began to harbor some hopes this was going to work.
Bolted MC onto booster, attached lines while allowing MC to drool all over to minimize any likelihood of air re-entering via the ports. Bled the entire system according to Volvo's green book this time - smooth strokes with all bleeders flowing through flooded hoses to beneath the surface of fluid in old brake fluid cans (got plenty of those!), starting with front left, front right - all of 'em, rear left, rear right.
No good. Pedal is a little better but not much. Still sinks nearly to the floor with vacuum on the booster.
Re-bled everything using the Bentley formula - rear left, front left upper, right front upper, etc. Ran the rest of the quart through. Nope. Got out the Motive and ran most of another quart through. No signs of any air at any point. Nope. Did it again with the Motive while pumping vigorously on the pedal. No luck.
All calipers are installed correctly, bleeders at top or middle as appropriate. All caliper pistons are correctly up against the pads which in turn are correctly up against the rotors. No lost motion swallowing up fluid. All work performed on a basically clean garage floor - no leaks of any kind anywhere.
So what the screaming %&*#@!!!??
Unless someone can hand me a clue here tonight or tomorrow I have to throw in the towel on this and pay someone to figure it out. It will be a first for me for anything but an alignment or car tires. I have always done my own work on everything.
To be humbled by a brake system. I can't show my face in public. I'll have to use an alias at a Volvo joint in some town far from here and beg for their help, prostrated, placing their feet on my head.
________________
For anyone who's interested, both the primary and secondary pistons, misleadingly named, have an effective area of about 0.3 in² and a stroke, if I recall my measurements, of about 1.3".
If one piston fails, that half of the system is gone. The remaining piston cannot supply pressure to the system fed by the failed piston. Doesn't matter which failed. Hence, there is no primary or secondary in my way of looking at it, just two pistons sharing a bore.
A stepped bore, you might note. Primary bore is about 0.877" I.D. and secondary right around 0.62" I.D. Too lazy to get out a bore gage so I measured on the squish of the secondary's O-ring. Primary has a cross sectional area a touch over 0.6 in² and the secondary 0.3 in². As the the two pistons move down the bore about half the fluid displaced by the primary fills the void left by the secondary receding down it's bore, leaving only about 0.3 in² actual displacement. Thus, both pistons supply basically the same amount of fluid to their respective systems despite the difference in bore diameters.
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One more thought...I have had problems in the past with stuck calipers/and or pistons. When fluid pressure builds, the rotor is deflected sideways instead of being squeezed between the two halves. You can see this with the help of a willing assistant-my wife's usually not willing. Anyway, the pedal moves until the offending caliper stops moving. I found this out the hard way after the 4Th bleeding exercise-the caliper guide pins were stuck and the caliper was only pushing on one side of the rotor-pedal travel until the play was taken up. It feels exactly like air in the system.
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Thanks for the input wtom24. Had the same thought when I found the rear left inside piston stuck, although I was looking at it from the perspective of not having a wheel bolted on to hold everything in place. Replaced that caliper just to be sure. Didn't help.
Since these cars have opposing pistons the caliper is fixed, which I love after dealing with supposedly floating calipers which often required attention to achieve that ideal, however briefly, unless the pins were pretty well lubed and had boots.
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Sinking pedal is probably an MC problem. Did you try the method I suggested about cracking the lines at the MC ports instead of bench bleeding? (It helps if the car is facing uphill to encourage air in the MC to the ports.) The pedal should firm up without vacuum.
--
1980 245 Canadian B21A with SU carb and M46 trans
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Yes, I've done that religiously since you mentioned it. And the pedal is not actually sinking. It's basically firm when it gets near the floor, just spongey.
Have not been so concerned about getting air in the lines in the past because, as I've said, I figured it was all a good opportunity to exchange the fluid. Volvo and Mercedes are making me damned paranoid, though, so I do whatever I can to reduce getting air in the system now.
I bench bled the MC canted to the left to get the ports dead at the top of the bore. Did it level at first because the primary port is toward the center of the bore - no natural ledge to trap an air bubble. Then tilted the nose up to purge the secondary. Also rotated it just slightly at intervals to be sure the ports were truly at the top.
I let it drool while attaching the lines in the car, then depressed the pedal just slightly and propped it with a board. Waited a couple minutes to allow any air to rise to the fittings, then cracked each one. Repeated till I got no air.
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I must say first off, and not to pull a 'Bill Clinton' on you, but I feel your pain! It just sucks to have a simple machine kick your behooten. Happens to me on a regular basis.
The only advice I could give would be to try and isolate where the problem is located. Try plugging both brake lines at the master and test. If it is stll bad it must the a bad master!, air in the master, wrong master or part# or bad booster. If good, hook and re-bleed one line while the other is plugged, etc, until the evil one is found. Good luck!!!!
--
'94 940 na Regina 150k, '86 240 180k Gary Gilliam Sumerduck, Va
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Been down that road and got bizarre results. Every part of the system I isolated gave me improved pedal. Couldn't say any one part was more a culprit than any other.
A question for anyone who might have the answer. Do Volvo brake systems pump up when they have air in them? That's a behavior that has been missing here. You can pump all day long on these brakes and you get nothing for the effort.
I have never known a vehicle that you couldn't pump up the brakes if air was the only issue. Except perhaps my Mercedes. Had a similar weird problem with it which I attributed to it not liking my vacuum bleeder. Now I'm beginning to attribute it to being European, which I used to view as a good thing...
My old trucks have the time honored Dodge characteristic of draining anything hydraulic if they're allowed to sit for any period of time. You just top off the reservoirs, check to see that you've got at least 3 or 4 pump brakes, then drive extra defensively for a bit until they slowly improve to 1 pump, then nice and firm. Always admired that about the old Dodges, the self bleeding I mean, not the self draining. Check 'em out at http://home.wmol.com/mechaniq/Index.htm.
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I believe that action you are looking for by "pumping" them up is not one that overcomes air inside the hydraulic system, but one that makes up mechanical work distance at wheel cylinders or caliper pistons. I've not felt that effect to a large degree (beyond a rotor knocking back the pads a bit) since having drum brakes with ineffective self adjusters.
Can't see how you could make up for air that way.
--
Art Benstein near Baltimore
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Art,
I guess in my old Dodges I always assumed I was compressing the air bubble. That if you were quick enough on the pedal the bubble couldn't push very much fluid back between pumps and that you would compress the bubble as the system pressure rose enough to apply sufficient force to the brakes. Bleeding the system would cure it, if I didn't want to wait for it to self bleed.
I just took the car for an evaluation drive, though, and now (blush) I think I've been misinterpreting the problem.
The only test drive I took was once down the length of a rather short driveway, then right back into the garage. Now I took it for a drive and I think, after all this effort, that I am exactly where I started from - too much pedal pressure required for too little braking and the pedal gets closer to the floor than is comfortable, but not heart beating close. Last time I tested it I had just gotten out of my wife's wagon which has excellent brakes. The disparity between the two was majorly alarming and may have made it seem a lot worse than it is, although it's pretty bad. Hmm...
I was thinking last night, like so many times before, it just can't be air. But I also thought, if it is, maybe it's in the outboard piston chambers where there would be very little fluid flow. So I decided to compress the pistons with the bleeders open into a bleed hose to see if it forced any air out. Got one little bubble on one side and that's it.
But in the process, I determined the lower pistons on both sides of both calipers really are not moving freely. I can get a little play in the pads squeezing against the calipers with vise grips the way you would to compress them - I'm guessing maybe 20 or 30 thousandths.
I don't know the diameters of the front caliper pistons but I guessed about 1.25". Translates to about 1.22 inͺ, which is about 4 times the master cylinder area. So if all four lower front pistons are moving around 0.30", that equates to the MC moving 16 times that far, or around a half inch. Then you take into consideration the pedal moves cosiderably further (calculated that, too, somewhere in all this but don't remember the ratio) Comparing pedal position to my wife's sedan, this is actually in the ball park. And the spongy feel would make it seem worse.
Now I have to do some thinking on this. Anyone have some experience with this particular issue?
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I've pondered on the ratio between linear piston movement, caliper to master, to help rationalize a lower pedal after doing caliper rebuilds, and especially after loading calipers with both of the shims provided with the factory pads.
The springiness, I guessed was imparted by fresh seals and pistons that moved easily, plus the rubber covered shims. The movement is quite visible at the wheel, just by using your right foot on the pedal with the caliper in view over the window sill. Applying the pedal and hydraulic leverage seemed to make it reasonable when compared with a car well broken in with stiff caliper movement.
But it was never anything near a full pedal's travel, just two inches instead of one maybe.
The pumping action would have to happen without any springiness, either from air or my supposed rubber effects. The fluid in the system would have to be at lower pressure than behind the master piston for the fill to pass the check valves behind the front cups and steel washers. For example, squeeze the pads well back from the rotor (if they're not new) and you'll pump several times to return them. If you put something elastic between that would push the pistons back in, you'd never pump them up, but have a very spongy ineffective pedal.
In your area and volume measurements, have you calculated the volume of fluid needed to bleed each circuit yet? I was thinking about that once, but Lucid had a practical answer to the question, obtained by using the blue and amber dyed Ate fluids-- a bit shy of one liter for all. Even that seems a lot, with new pads. The proportioning valves look to hold very little from what I recall of a cutaway drawing, and the octopus couldn't add more than a fistful.
--
Art Benstein near Baltimore
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After noticing the play on the pad, squeezing with the vise grips (almost spell it "vice" grips each time, but that would be the Governator, eh?), I did just what you mentioned, hanging on the door with my head through the window pushing on the brake. I could see the pads move, mostly at the bottom. Each time I released the pedal they would visibly relax again, so there is some springiness in them, somehow.
These are factory pads with 50% or better left on them, showing no signs of heating up. I could still see the pattern in the rubber on the shims. The rotors are ventilated Brembo's with around 20K on them, in very good condition.
I wonder if the bottom pistons requiring a fair amount of force to return have worn the pads slightly more at the bottom and now they have to flex to lay down flat on the rotors?
Going to pull a wheel off the wife's 245 and take a look at how much free play is at the pads there. That car's brakes are firm and very effective with very light pressure on the pedal. It'll make a good example of the ideal for comparison.
As for the total volume of the brake system, looks like about two gallons and a quart from where I stand at this point!
Really, I lack the motivation to calculate it. Too many variables. You'd have to nail down the brake line I.D. deadnuts or the cumulative error would kill you. You've got hose I.D.'s, the octopus, etc. I'm slow enough as it is!
Last time I did something similar was to determine where the blockage was that didn't allow the kitchen sink to drain. Let it drain overnight then carefully poured measured volumes of water down the drain till it appeared in the sink. Calculated the volume of the pipe and, knowing the volume of water required to get to the blockage, determined it was well down the large tile leading to the old drain field. Boy I was proud of my technique!
A friend determined the same thing in a minute, without so much as a pencil and paper. He ran hot water down the drain and went downstairs to feel how far it made it.
Oh well.
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Really, I lack the motivation to calculate it. Too many variables. You'd have to nail down the brake line I.D. deadnuts or the cumulative error would kill you. You've got hose I.D.'s, the octopus, etc. I'm slow enough as it is!
Chuck,
As Art said, I really have found it to be less than a liter, total. This is based on several 240 bleed flushes, using the different color Ate fluids. It's quite obvious, especially flushing with the Super Blue -- "When the Blue comes thru you know it's new."
I have yet to get cute about flushing the Blue fluid with Amber.
Maybe, "When Amber's thru, it's bye-bye Blue." (?)
Press on, as they say,
Bruce
P.S. (Truth in Bleeding)
I must confess that my flushes did NOT involve first pushing the pistons back to expell old fluid via the bleeders. I should have done this, and will the next time. But that's the only thing that might increase the total fluid required, above the "less than a Liter" I've routinely observed.
--
Bruce Young
'93 940-NA (current) 240s (one V8) 140s 122s since '63.
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I'm glad you're keeping your sense of humor in shape to entertain others, Chuck. Yes, as soon as Lucid told me his estimate, I forgot measuring brake lines and so forth. The only reason I wanted the estimate was to be absolutely certain I'd run enough through to flush each circuit of air. Figured I could calibrate the "coke bottle" to borrow the image from one of the manuals. I've put several times the amount through these, still questioning my results sometimes.
Speaking of variables, if you had seized front pistons and wedge-shaped worn pads...yes, I can envision the newly freed pistons being met by a non parallel surface. Goes along with increased braking force. But I don't know how to connect this with a rear caliper replacement.
If you suspect, as I did, too much give in the caliper end of things, how about removing the pads, shims and all, and just inserting new pads without shims, for a stable and solid load to the fronts?
--
Art Benstein near Baltimore
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Art. That's the plan for tonight. Got a new set of pads on the shelf. Hate to pull decent looking pads and put a new set in there, but...
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Well,if the lines are removed and plugged at the master and pedal is normal then the problem/s have to be downstream. As improbable as it might seem, there must be some stinkin' air in there somewhere. Since all the calipers are good and pads firm against rotors, it would have to be a slug of air in the proportioning valve/pressure switch. My book cautions removing the switch from the valve before bleeding. I had always assumed that it was to prevent setting it off, but maybe it would hold/prevent air from being bled??? Guess you could also try tapping on it while bleeding #2 left front upper and #3 right front upper? And I guess bottoming out all caliper pistons by compressing and opening bleed screws before bleeding sequence to rule out anymore possibilities of trapped air.
Nice truck! I have a buddy that you would have to beat repeatedly with a large wet stick to get him away from that Dodge. I would go for the motorcycle.
--
'94 940 na Regina 150k, '86 240 180k Gary Gilliam Sumerduck, Va
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Thanks on the truck. It needs some attention. Served as a thankless workhorse for the last twenty years with the exception of rebuilding the engine.
You mentioned compressing the calipers. I thought of the same thing this morning while laying in bed thinking I should get up. Going to give it a try in an hour or so. This whole thing is so bizarre.
Why would a Volvo be more susceptible to trapping air than any other vehicle? Disconnected the lines to the rear just to eliminate the proportioning valves, since I don't know what they look like inside. That firmed up the pedal a little, but nothing to write home to mom about. So this morning, I thought, depress all the pistons just to minimize any influence those volumes are having. Probably attach bleed hoses and crack the bleeders as I do it in hopes at least some telltale air will emerge to let me know if this is part of the issue.
I'm almost out of DOT 4 and it's Sunday on the shores of Lake Michigan. You don't buy DOT 4 on Sunday around here. It's hard enough to find it during the week. I've put just over two gallons through this thing.
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i dont see it in your post, did you replace any calipers? you seem to have covered everything. i am one of the clowns that had a simular experience but after much dismay i realized i had the front calipers swapped and the bleeder was on the bottom and couldnt be bled, i figured this out after i did everything you posted about. but i have read more posts about the mismatched calipers that lucid referred to. about one and one halp years later and im starting to show my face in public. goodluck from hardknocks
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Mike, I understand the problem when the bleed screw appears on the bottom, but I've never actually seen for myself the mistakenly assembled front calipers with mismatched halves. Does this prevent fluid from entering the outboard buckets, or does it just present another unbleedable air pocket, like when the right caliper is installed on the left wheel?
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Art Benstein near Baltimore
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Art, I've seen this once and heard of it at least once here on the board.
To visualize the effect, I had to make a sketch, slice it vertically, then invert the outer half and hold it up to a light.
If I got it right, the outer upper cylinder is OK, but its bleeder will appear to be for the outer lower (since it should really be a lower cylinder on the other side of the car). As a result, the the 2 upper cylinders and passages are as they should be in the form of an inverted "U", but with an extra bleeder low at the outside, connected to the (now) upward leading passage. In bleeding from that misplaced "lower" bleeder, you will actually be drawing fluid from the upper circuit, thus screwing up the assumed bleed sequence.
The real problem is that there will be NO Bleeder for the outer lower cylinder. The only bleeder for the upright "U" formed by the two lower cylinders/passages is the normal one on the inside. This leaves X amount of unbleedable air space leading to the lower outer cylinder.
Now get out pencil and paper...
--
Bruce Young
'93 940-NA (current) 240s (one V8) 140s 122s since '63.
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I believe I will print your post and lay it on top of the box of separated caliper halves ready to return for core charges.
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Art Benstein near Baltimore
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Hello hardknocks,
Yes, replaced the rear left, but the bleeder is up top where it should be.
I had this one sitting in the loft for quite awhile because I discovered it was rebuilt after buying it from a reputable internet business. Re-read their blurb which all but stated it was Volvo factory new. Certainly did not state it was rebuilt. Got it to address a very sticky piston but vacillated about using a rebuilt. Vacillated so long I couldn't return it.
When this issue came up I figured I was being too picky. I suspected the stuck piston might be causing some kind of play since the wheel was off, allowing the rotor some freedom to wobble. Immediately noticed the bleeder wiggles in it's bore when its open. Enough to suggest the threads are at the threshold of stripping. Also siphons air uncontrollably if you ease off positive pressure for the briefest moment while bleeding. May as well order a replacement right now because the bleeder will be rusted fast in no time due to all the clearance in the threads.
That's why I don't do rebuilt, usually.
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Chuck, the only thing that jumped out at me was, "Re-bled everything the conventional way - stick propped against seat - ".
The only time I use a pedal prop stick is to keep the MC from draining when I have lines open for any reason. It keeps fluid in the MC, so bleeding would be impossible, IMO. I assume the prop wasn't in place for all your bleed sequences.
You didn't mention checking for mismatched front caliper halves. I think I posted that in your last thread, but if not, make sure the outer half DOES NOT have a punch mark, or "dimple" on the top, near the joining line. Both halves should be marked on the bottom.
Sorry I can't be more help.
--
Bruce Young
'93 940-NA (current) 240s (one V8) 140s 122s since '63.
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Hello again Bruce,
I meant pump pump pump, prop stick against seat, bleed, ad infinitum.
Although, through all of this I have learned that after filling the bleed hoses with a couple cycles of the pump-prop-bleed routine, you then simply open the bleeders, while the board holds the pedal to block fluid flow as you so helpfully suggested, then smoothly stroke the pedal and watch the fluid index one way to the bottles. Discovered, after the fact, that this is the way the Volvo factory manual says to do it, in the abcense of their bleeding equipment, which appears to be a pressure bleeder that forces fluid into the bleeders and in reverse up to the master cylinder. Ever hear of that?
With the exception of the caliper I replaced on the rear left all calipers are original and undisturbed. Since there are no leaks, and they're all free and appear to be functioning correctly I just can't imagine how they might contribute to the issue.
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Chuck,
I'm not understanding what part the prop stick plays here. It is not part of any "conventional" bleeding method I know of. I'm sorry to say it sounds absolutely wrong to me.
I have both the 240 and 700/900 Volvo brake manuals, and only the 7/9 one shows the pedal being propped. But that's not when bleeding, it's when removing a caliper, etc. as I said, to keep the fluid in the MC.
I don't see how you got any fluid bled thru the system with the reservoir ports blocked, which is what the prop does.
--
Bruce Young
'93 940-NA (current) 240s (one V8) 140s 122s since '63.
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Sorry Bruce. I'm not being clear.
It's the old routine of one person doing a two person job. I pump up the brakes (except they don't actually pump up in this instance) then prop the pedal against the seat with a 2 x 4 to hold pressure on the system. Then I run to the bleeder that currently has the focus, crack it open till the fluid stops flowing (and yes, on some vehicles I have owned this results in the board falling to the floor if you relieve too much pressure, releasing the pedal, and sucking air back into the caliper if any is available in the bleed hose), screw the bleeder shut, pump up the brakes, prop, repeat.
After being sure I've moved enough fluid into the bleed hose that pumping the pedal won't pull any air back in, I stroke the pedal a number of times, then reprop it with the board to hold the fluid from sucking back while I screw the bleeder tight.
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if you have the motive pressure bleeder this makes it a one man job. i would try again without any prop stick. i put a clear hose on the bleeders and the other end in a coke bottle partially full of brake fluid, probably not needed but just in case. i dont pump up the pressure bleeder until gravity fills the clear hose. i also tap on the brake lines under the car while pressure bleeding and jack up the back of the car. im not sure if the rear calipers can be mismatched or the front calipers or both. alot of people have had mismatched calipers. good luck
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Ok Chuck,
I think I get the theory now. I've just never run across it before. But it has no part in your subsequent pressure bleeding does it? I guess I'd better bow out now to make room for some helpfuller tips. You don't need more questions, I'm sure.
Bruce
--
Bruce Young
'93 940-NA (current) 240s (one V8) 140s 122s since '63.
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No, I don't use it while pressure bleeding.
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Carefully reading, I know you've covered this several times, and I found your attempt to isolate with plugs in the rear line ports of the distribution box a telling clue. When you plugged these ports, were they brimming? In my car the rear ports are the high ones, leading me to the conclusion I needed to bleed rear calipers even though I'd not opened anything back there. Also it gave me a hint as to why Volvo says to bleed the rear first.
Anyway, the experience I had last weekend calibrated my sense of how much air did what to the pedal: One octopus-ful on just one side makes almost the full pedal travel ineffective at stopping the car. Fill that void and the pedal is right up top. I added that learning to the information you supplied last time about a 3" length of brake line full of air - the construction of your deadhead plugs, if I recall.
I enjoyed reading your explanation of the equalizing method between the primary and secondary fluid volumes. The "pressure" device you see being used in the Volvo manual is really a vacuum bleeder using shop air and a venturi.
--
Art Benstein near Baltimore
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Hello again Art,
When I disconnected the rear lines at the "octopus" (I like that) I had the brake propped to keep things from drooling all over. In retrospect it would have been a better idea to let the fluid purge. Anyhow, had some fluid present but couldn't say how much was dripping from the disconnected rear lines, which are on the top on my block too, and how much from the octopus. I was in a bad place to see, on my back under the car.
I did bleed my plugs after they were in place. Only needed to crack the fitting at the dead end very briefly to purge the air, with the board propped against the seat cushion supplying pressure, so I assume the octopus was pretty much filled. I really need to make up a nice short set of plugs.
Thanks for clarifying the Volvo factory bleeding rig. I just couldn't imagine pushing fluid in reverse along with the crud that's all too likely to be around the bleeders. Don't know where I got the impression they were pushing instead of pulling. Something in the text, but that's at the other house.
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Just a thought on that brake pedal propping. If you are using the foam of the seat to provide pedal pressure, you would indeed have some useful working pressure result if it really allows some pedal travel. Otherwise, it is just, as Lucid points out, shutting off the reservoir ports and keeping the piston located in one place, so the only pressure that will result on the hydraulic fluid in the circuit will come from that air bubble you're pursuing.
I have to think using the Motive would be far superior to depending on your seat cushion foam for pressure.
--
Art Benstein near Baltimore
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It does give some travel, so it's fairly effective.
My objection to the motive for a quick check like that is loading a fair amount of fluid into it which I then feel is subject to sucking up moisture if you don't use it all. And, of course, I've hoped each attempt would result in victory.
May have to look into your golf tee idea, but with my luck it'd get spit into the reservoir because I'd certainly forget to remove it some time or another too.
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My objection to the motive for a quick check like that is loading a fair amount of fluid into it which I then feel is subject to sucking up moisture if you don't use it all.
I understand and agree with your objection. But with a full rez, you could use the motive empty -- just for pressure.
That's how I've done it for years now. An adapted MC cap with hose to a MityVac pressure port, with an old Vac/Pressure gauge t'eed into the hose.
I pump the rez up to 12-16 psi and start bleeding.
Yes, I do have to keep an eye on the rez level, but I'm careful about that. And overall, it takes surprisingly little topping off attention to go all the way around the sequence.
I learned early on that it's good to relieve the pressure before opening the cap.
--
Bruce Young
'93 940-NA (current) 240s (one V8) 140s 122s since '63.
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