How to get 240 brakes lines to bleed or unclogged?

Corvids · Post by **Corvids** » 19 Jul 2009, 22:24

Have a 91, 240 with ABS and 290,000 miles. Had brakes and discs replaced, then both front brakes would not bleed and were not making metal contact. Some brake fluid flowed out when old pads were removed. Mechanic, not that familiar with Volvos, tried flushing all four brakes with little to no success, and had some fluid to come out of ABS from tapping on top of it. I am not sure what degree or technique of flushing he used. I think he tried also to adjust the proportioning valve. He thinks the ABS might need replacing, but no light came on indicating a malfunction.

A couple of other mechanics thought there might be a blockage in the front brake rubber lines that connect to the hard line, and to disconnect and flush separately. The mechanic did not try this, and does not want to go any further.

By my description does this sound more like a blockage in the brake line or ABS from dirt or sludge, and if so, is there some way to power flush, suck out, or try some dissolvent or cleaner fluid to clear?

Or could the ABS malfunction for some reason? Is there some way to narrow down and rule out what part of the system is not working such as fuse, relay, pump, etc? If the ABS needs replacing, it may be too expensive for me to repair, considering the miles and the car's worth. Are there rebuilt cheaper ones? Rather than possibly junking, can the ABS be bypassed, where the brake lines can be disconnected to and from the unit and reconnected and operated safely without the ABS? The 91 had ABS as a option that year. It is hard to imagine junking a car that still runs well because of a brake job.

Post by **billofdurham** » 20 Jul 2009, 11:52

Welcome to Matthew's Volvo Site.

I am amazed that a mechanic can't sort out a simple bleeding problem.

Some brake fluid flowed out when old pads were removed.

Where did that fluid come from?

Old bleed nipples sometimes get blocked and need to be replaced if the rubber cap has been missing for any length of time. Try removing the bleed nipple completely to see if there is any fluid flow without it.

Bleeding of the brakes is best done with a power bleeder of which there are many makes/types on the market. Mine, which is about 30 years old, works off the valve on the spare tyre. Don't try sucking as all the valves are designed to work in the other direction and you could cause major damage to the system.

On your car the bleeding sequence is left front, right front, left rear and right rear. If the calipers are fitted with three bleeder valves open all three together.

If the ABS were causing problems the light should come on so, for the time being, that can be discounted.

A couple of other mechanics thought there might be a blockage in the front brake rubber lines that connect to the hard line, and to disconnect and flush separately.

Possible, I suppose, but I would have thought any blockage would be pushed as far as possible i.e. to the bleed nipple. I would also be doubtful that it would affect all the wheels.

Bill.

Corvids · Post by **Corvids** » 20 Jul 2009, 13:47

Thanks for replying, Bill. I am relaying spotty information from the mechanic. I am not sure how the brake fluid initially came through the brakes lines. I assume this is normal when the old pads are removed, that there is some spillage. Even the service manual mentions that.

What I understand is that 240 Volvos with ABS are to be bled the opposite of those earlier models without ABS, starting with the rear, furtherest away from the master cylinder and work towards the front. I don't really understand how the the back brakes won't bleed now when the front brakes were done. I think they got the right front brake to bleed the most.

Thanks for the suggestion about removing the bleeding nipples. Is that pretty simple to do? The mechanic I have does not want to do any more work on it, so I will either have to find someone who wants to do this there, or tow 40 miles to mechanics that knows Volvos better. I am in a bit of a bind in what to do next. Thanks for your help and any other suggestions would be appreciated. John

Corvids · Post by **Corvids** » 20 Jul 2009, 13:47

Thanks for replying, Bill. I am relaying spotty information from the mechanic. I am not sure how the brake fluid initially came through the brakes lines. I assume this is normal when the old pads are removed, that there is some spillage. Even the service manual mentions that.

What I understand is that 240 Volvos with ABS are to be bled the opposite of those earlier models without ABS, starting with the rear, furtherest away from the master cylinder and work towards the front. I don't really understand how the the back brakes won't bleed now when the front brakes were done. I think they got the right front brake to bleed the most.

Thanks for the suggestion about removing the bleeding nipples. Is that pretty simple to do? The mechanic I have does not want to do any more work on it, so I will either have to find someone who wants to do this there, or tow 40 miles to mechanics that knows Volvos better. I am in a bit of a bind in what to do next. Thanks for your help and any other suggestions would be appreciated. John

myspv · Post by **myspv** » 21 Jul 2009, 08:18

Corvids wrote:Some brake fluid flowed out when old pads were removed.

I am confused here, and/or worried. Maybe this is what the mechanic told you, you don't really understand what he meant and you're just relaying the information. When fitting new pads, you have to account for the increased thickness of the pad material. So that you don't push old, dirty fluid back up into the system it is a good idea to open the bleeder nipples when you push the piston back into the caliper. Let's hope that he did this, and that this is the fluid coming out which you described above. Let's hope that no fluid leaked out around the rubber boots around the caliper piston.
This would not account for any blockages further up in the braking system.
Prior to all of this (new pads, attempt at bleeding the fluids) were the brakes okay?

In any case, what Bill said is correct. This guy should be using a pressure bleeder. I use the product made by Motive - it turns a job that can be a real pain into an easy one-man job.

And just FYI: bleed your brakes once a year. Some people tell me that this is excessive. I don't think so.

Corvids · Post by **Corvids** » 21 Jul 2009, 10:36

Thanks to all,

Yes, he did open the bleeder nipples and this is where the fluid came from. I also found out that he used the manual method and did not power flush.

Before I had the brakes done, I had good brakes, and needed the discs replaced because of wear and braking vibration. Thinking back, I do remember having a few instances over a period of months, and maybe years, where the brake pedal would sometimes give way or slip down, and then would go away and maybe not do again, even for months. I always thought it might be air in the line. Could this be the master cylinder starting to go bad?

When the mechanic first tried to flush the system the brake petal was firm to push on, although the front pads were not making contact. There was not any brake fluid moving out of the master cylinder. After they said they worked three hours on it, I checked the brake and now it goes down to the floor without any resistance. So now I think the master cylinder may be damaged. If they were getting very little fluid to go through the system, I would think there would still be resistance on the pedal. That is why I think the master cylinder is now not working properly. Does this sound logical?

Now I am trying to find another place to tow the car, where I agree, it should be power flushed first, and then see if it needs a master cylinder, in that order. Do you agree? My objective is to go as far as power flushing and replacing master cylinder to get the brakes to work, but if it comes to also replacing the ABS, I may have to stop. I would sure like some mechanic I take it to now that would know enough to tell me if it is, or is not the ABS, before I do all this work.

I am not sure why the mechanic could not get fluid out from the ABS, which he thinks might be bad, unless he was not getting fluid form the master cylinder. I am looking more at the master cylinder being bad. Does this make sense? If now the pedal is going to the floor, it looks more like they could have possibly damaged the master cylinder. Looks like I am going to have to talk to mechanic again, but they don't explain very well, where I have to ask all the questions. Why I am asking all of these questions is so the next place I take it, they do something different than what was done before. Thanks again, John

Post by **billofdurham** » 21 Jul 2009, 12:20

First, an apology. The bleeding sequence I quoted was for the earlier version with ABS. The sequence you quote is the correct one for your car.

You certainly seem to have a poor mechanic if can't explain, in layman's terms, what he has done and what he thinks is wrong. The braking systems on the older Volvos don't need a rocket scientist to work on them.

The master cylinder may well be the culprit but if he has allowed air to enter the system and doesn't have the ability, or a power bleeder, to get it out then the brake pedal will hit the floor regardless of the condition of the master cylinder. Your experience of the pedal occasionally going to the floor is a sign of the master cylinder seals starting to fail. This can go on for some time as you have found. Air in the system would allow the pedal to go to the floor, or near enough, every time.

it should be power flushed first, and then see if it needs a master cylinder, in that order. Do you agree?

Yes. If the power bleed gets all the air out and the pedal is still going to the floor then it is a master cylinder problem.

Bill.

Corvids · Post by **Corvids** » 21 Jul 2009, 19:07

Living in a small town, I am very limited with who can work on foreign cars, but I think I found a place specializing more in European cars that will do better with Volvos. Mechanic will assess the situation, but he thinks already that the problem has more to do with the master cylinder. I think he wants to try the manual bleed first, which he prefers, but is capable of doing some kind compressed air power flush. The last place I had it, the power flush was broken, so I don't think they used it that much. If it had been working, I think there is a chance I would not be so far in this predicament.

If by chance the ABS is bad, mechanic may be able to get a rebuilt one, or too cost prohibitive, suggested modifying brake system without ABS. This was an option I was thinking about that might save a good car, rather than possibly junking. My thinking is that the 91 was the first year it was introduced as an option, and the early unit may have had some bugs anyway. I figure that the basic 240 that has not changed much from the 80's having no ABS, so all those years the brakes worked reasonably well.

Thanks so much for the good advice. Good thing. You helped to keep my frustration level down. Thanks, John

Corvids · Post by **Corvids** » 23 Jul 2009, 20:35

I am happy to report that the new mechanic diagnosed and solved my problem...really clogged master cylinder and old brake fluid. So brakes work fine now. Thanks for all the suggestions.

Post by **billofdurham** » 24 Jul 2009, 11:46

Thank you for the update.

To prevent a repeat of this problem Volvo maintenance schedule specifies "Drain, refill and bleed the brake system" every 30,000 miles.

Bill.