Hi,

The following is on a 1990 244 (Non-ABS). Bleeding procedure performed with Motive Brake Bleeder.

Recently I finally got around to a brake procedure that had long by waiting in the wings (this is on our first 90 244-has been sitting for a few months) due to various little/big repairs.

Anyway, what needed done was for the brake junction (octopus) at the front of the car to be replaced. I bought a boxed OEM New Old Stock Bendix unit from eBay. Drained all fluid via bleed screws (I wanted to make sure bleed screws on calipers weren't seized also). At that point I had noticed there was only a little dribble from the Left Rear caliper, but I proceeded on to figure I would deal with it after replacing the brake junction. Replacing the junction went off without a hitch.

It came time to bleed and that LR (driver) caliper wouldn't produce. I pressurized the Motive Bleeder a bit more- up to 20 PSI, still nothing.

I then figured it must be the flex hose (original hose looking somewhat battered) so I replaced both rear hoses since I had them on hand and nothing was seized. That went off without a hitch.

Still nothing from the caliper when trying to bleed it.

I then figured, must be clogged caliper.

Replaced that and still got nothing when trying to bleed the "new" (reman) LR caliper.

Now the only other thing I fiddled with/replaced was brake hoses and lines at front left while waiting on caliper, that was a procedure that didn't go off without a hitch, but that is another story. Those front lines/hoses were replaced though after a bit of a struggle.

***Additionally-I haven't had a battery hooked up to it as I didn't think it was need (and I was charging it) but I don't think this would have any affect, correct?

Any help/advice is greatly appreciated.

Thanks,

Travis

Finally got everything pretty much squared away (brake pedal is very very slightly soft, but its suitable).

After I had bled the brakes after installing master cylinder (mc was also bench bled) the brake failure light was still lit, even though at this point the pedal was good. I then unscrewed the switch from the brake junction, replaced it and the brake failure light stayed off?

Now onto other awaiting issues...

Thanks everyone for all the kind advice and help,

Travis

I messed around with this brake problem several more times.

After trying to get steady fluid from the rear driver side caliper that I was having trouble with I finally got good flow from it by tapping the left side of the proportioning valve/brake modulator with a dead blow hammer. After several taps, fluid started flowing from the rear driver side caliper.

Unfortunately, this worked after trying various methods such as help things along by using the brake pedal and using a higher pressure on the motive bleeder. Pretty sure one or both helped destroy the master cylinder as after bleeding several times the pedal was to the floor and the brake failure was staying illuminated. After the last attemp I then noticed bubbling going on inside of the brake fluid reservoir.

So the next step is to install a master cylinder. The one I picked up at autozone was brand new, under the duralast brand. It is made by Fenco, looks solid and it conveniently came with a bench bleed kit. It was $42. Hopefully the installation will go off without a hitch.

I will repost when I am finished.

Travis

Hi Travis,

FYI.

go to
http://www.davebarton.com/volvo240bigbrakes.html

then, scroll down to
FRONT/REAR BRAKE BIAS:

Try pressurizing from the caliper hard line forward...

No flow...you have a crushed line or serious blockage.

Flow...the caliper might be faulty.

Hi Onkel,

Thanks for the response. Not sure what you mean by pressuring from the caliper hard line forward. I can only pressurize from the master cylinder with the Motive Bleeder.

I was thinking my next move would be to remove the hard line going to the caliper and see if it flows out of the hard line.

Travis

OUII suggested pressurizing from the rear forward and I think he's on the right track as far as pinning down a possible blockage but I'd suggest disconnecting lines moving upstream--using a compressor or air tank blowing from that point back (with the caliper line disconnected) or forward-your choice-part by part. You don't want to push any possible debris into the caliper, the rear pressure limiting device, octopus or master cylinder. -- Dave

As delivered...sure the Motive is a one trick pony. It is just a garden sprayer with a gauge and MC cap instead of wand. Either use some creativity with the Motive or get a $6 garden sprayer, do not attached the wand and stick the hose over the bleeder nipple.

Or worse... like the proportioning valve* is rusted.

(The expense and difficulty in replacement of this part alone is probably the most effective incentive to maintain a flushing habit.)

* if you google this, you'll find even the parts suppliers don't know what this is, displaying the octopus, or differential pressure sensor instead. The proportioning valves (2) are under the rear seat.
--
Art Benstein near Baltimore

“Always code as if the guy who ends up maintaining your code will be a violent psychopath who knows where you live.” - John F. Woods

Hi Art,

Thanks for your reply.

I actually had thought of that proportioning valve and looked into it a bit. There's a very tiny amount of info in Bentley and Haynes manuals-I think in one of the manuals it is called a Rear Brake Modulator or something. Couldn't really find anything in the archives here either pertaining to it.

When I looked it up online it seems to be only available as an OEM Volvo part which at the cheapest is $330 and various places listed it as no longer available.

My next move is to remove hard line from caliper and check flow from it, after that I figure I'll soak and re-soak fitting of the hard line going into the proportioning valve/modulator to rule it out.

Thanks,

Travis

Crap...forgot about those...yeah, check that.