Pressure bleeding question

Post by **rgk** » 27 Jul 2010, 12:39

I have heard that one the front calipers it is recommended to bleed all three bleeder nipples at once. Is this only recommended with the braking method, or with the (hand pump) pressure bleeding method as well? If so, am I supposed to fill a jar with fresh brake fluid and place the other two hoses in it so that the brake fluid is being sucked through the caliper three ways? Doesn't this seem wasteful?

Post by **billofdurham** » 28 Jul 2010, 12:11

The fluid in the jar is not sucked into the caliper. It is there so you can see when the new fluid is bubble free i.e. all the air has been expelled. You don't need to start with a full jar, just enough to immerse the end of the bleed hoses. The jar will fill itself as you push the fluid through the system

On the 240 of that era it was recommended that the rear wheels be raised about 2" higher than the front wheels when bleeding. The bleeding sequence is Right rear; Left rear; Right front; Left front. On the front wheel, as you say, all bleed nipples should be open at the same time whether using the brake pedal or a pressure bleeder.

The attached should help:

'85 brake bleeding.pdf: (910.81 KiB) Downloaded 204 times

Bill.

Volvofix1 · Post by **Volvofix1** » 13 Aug 2010, 16:05

In my Volvo shop we only opened one bleeder at a time but you must follow a certain bleeding sequence which will be in a Haines manual.

Dick K. from Fla.

Retired MVS Contributor · Post by **Retired MVS Contributor** » 14 Aug 2010, 07:15

The recommendation to immerse the bleeder hose in brake fluid was intended to be used if the pedal-pumping method was used and served two purposes: (1) it allowed you to see the air bubbles, and (2) it prevented air from being sucked back into the caliper when the pedal was released...If you are using a pressure bleeder, both become irrelevant...There also is no need to open all the bleeders at once...The constant pressure maintained by the pressure bleeder will keep everything in place until the selected bleeder is opened...Do the lowest bleeders first and the upper ones last...

Post by **mgjh** » 14 Aug 2010, 07:28

I'm also having trouble bleeding. I followed the sequence in Bentley (LR, LF top, RF top, RR, RF lower two, LF lower two), but can't seem to get air out of the system (pedal travels to floor). Although previous posters say it's not necessary to do both front chambers at the same time, does it hurt at all? It would make my next bleed attempt easier.

Retired MVS Contributor · Post by **Retired MVS Contributor** » 14 Aug 2010, 08:24

mgjh wrote:I'm also having trouble bleeding. I followed the sequence in Bentley (LR, LF top, RF top, RR, RF lower two, LF lower two), but can't seem to get air out of the system (pedal travels to floor). Although previous posters say it's not necessary to do both front chambers at the same time, does it hurt at all? It would make my next bleed attempt easier.

Are you using a pressure bleeder?...Or pedal pumping?...If the pedal travels to the floor while you are bleeding, it is supposed to do that, but if it does that when all the bleeders are closed, you have a problem...The most logical would be a by-passing master cylinder...Leave the cap off the master cylinder and have someone press the pedal while you watch the master cylinder...If it shoots fluid out of the filler, it is by-passing and needs to be replaced...