From the 700-900 FAQ (click FAQ at the top of each brickboard.com page):
Non-ABS Brakes
https://www.brickboard.com/FAQ/700-900/Brakes.htm
Or ABS?
https://www.brickboard.com/FAQ/700-900/BrakesABS.htm
If you are bleeding brakes using the brake pedal, if you press to far, even on a new ATE (or Girling?) Brake Master Cylinder, you can displace seals in the piston bore. (Or the seals are on the piston?)
Are you bleeding the brakes yourself? Like with the fluid dripping down the caliper, or with a hose between the caliper bleed nipple and a container of old brake fluid? Either way, air can get suck back in through the thread interface of the bleeder nipple and the brake caliper body.
Else, use a Motiv Power Brake Bleeder or the like. These use a container full of your fave DOT 3 or DOT 4 NEW brake fluid, you pressurise it with a pump of spare tire air (if this was 1967 and we're working on your VW Bus), and open and close the bleeder valves as the clean fluid comes out the (hopefully transparent) hose connected to the brake bleeder.
If no ABS, you have to pay some special attention to the two brake check valves at the rear of your 1989 740-series Volvo. Something about raising the rear of the car up a little higher. Or, as you power bleed the rear brakes, gently tap the brake check valve to dislodge any air bubble in there.
If you have ABS, you may want to run the ABS brake pump after you have clean fluid coming out the furthest brake bleeders so as to remove old brake fluid in the ABS pump.
There may be a more efficient way to do this using a power brake fluid bleeder whether you have ABS or not. You may want to call around to see if you can rent or borrow a brake power bleeder. It has to be clean, if it is not new.
Use at least 91% anhydrous Isopropyl alcohol to clean away the spent brake fluid in your power bleeder tool and let dry before storing again. You do not want the brake fluid to remain anywhere inside the power brake bleeder tool.
Other more qualified than I shall chime in with better suggestions, I'm sure.
How are them rear wheel bearings on that 1989 Volvo 740 doing for grease pack? They need some NLGI-2 grease pack love, also, like the front wheel bearings.
Questions?
Hope that helps you.
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