240 '87 240 brake pedal intermittent reduced travel and performance

[everyhumanvovo]

Last two days, there has been a single time right after starting where the pedal does not press down more than an 1" or 2" and it feels as if the car will not stop. Fortunately, both times it has stopped before catastrophe. Thereafter, it seems to have normal travel and braking performance. Any insights greatly appreciated.

 

[cleanflametrap]

Last two days, there has been a single time right after startingwhere the pedal does not press down more than an 1" or 2" and it feels as if the car will not stop. Fortunately both times it has stopped before catastrophe. Thereafter, it seems to have normal travel and braking performance. Any insights greatly appreciated.

You have a sticking piston or jammed pad. It is time to fully inspect your brakes at the wheels, making sure rust has not bound up the pad in the caliper ways and the pistons retract smoothly.

The remanufactured calipers come with an odd assortment of cylinder dust seals and none I've seen are as tight and accurately fitting as the Girling or ATe replacement seals. If you peel back the dust seal you might find rust on the piston.

Also, look for uneven pad wear. You need to do this soon, because a sticking front caliper will boil fluid in both circuits and then the pedal won't hang up, it will go right to the floor.

 

[bobxyz]

Check your brake booster too - maybe it's leaking down overnight? Until you find the issue, get in the habit of trying your brakes before moving and just after you get going.

 

[cleanflametrap]

Last two days, there has been a single time right after starting ...

Say, if I should have read this as "starting the engine" instead of starting off after stopping, the booster bobxyz suspects is a better answer. I would look for a soft spot in the large hose from the manifold to the booster check valve. Right where it exits the manifold nipple, the blowby oil softens the hose and eventually it collapses under vacuum, and if the "won't press down" is your brakes lacking power boost, that's it.

 

[everyhumanvovo]

Thank you much! I went to Swedish Engineering here in Eugene and another brake shop. Swedish Eng. thought brake booster or hose. I bought Volvo hose to fit from booster to manifold, and a backup used check valve. They thought my hose looked ok. A collapsing hose sounds possible. S.E. also suggested master may be going. They also said it could be leaking internally and not show lower fluid in reservoir. Both did not think it sounded like sticky calipers or pad issue. Had tires rotated and they thought pads looked good also.

 

[everyhumanvovo]

hmmm I love this car. Never happened again. I think though in certain situations air can gather in lines and cause these issues. Like if a vehicle sits, but it goes away after a litte use. Maybe change the fluid