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New motor is in the wagon and just finishing off little jobs before regoing the car. Took or a quick drive up the street and the brakes are woeful!

Lifted rear of car and had daughter put foot on brakes, and could turn the wheels (just).

Pulled calipers apart, all working OK and free movement. Bled rears, and plenty of fluid coming through. Brakes still terrible.

Any ideas?

I was thinking the booster may not be operating correctly - pedal feel is pretty hard and need to really stand on them to pull car up.

With the diagonal braking system you should be bleeding all 4 brakes, not just the rears.

As for the booster, perhaps you've got the one way valve around the wrong way?

Yes, you're right Tim, should have bled all 4 and did just that today. Still no good. Took to a Brake repair shop for their opinion this afternoon, and he tended to agree that the booster is the problem, however will not know until it's pulled apart. They are doing that tomorrow for me.

The brake system was not touched during the engine swap, so if one way valve is in back to front, it has been that way for a long time!

I will post the diagnosis once I find out for sure what the problem is.

Cheers

Its unusual for a booster to die unless you have a leak of the master cylinder. Try filling the fluid level and then crack the 4 bleed nipples on the calipers, the one with the less fluid or non coming out could be where the problem is coming from

How did you go with this Willie as i am having the same problem with my brumby
It has 4 wheel disc brakes and a new master cylinder and the booster is holding vacum but the brakes are dredfull so i am following your post with interest
Jeff

Jeff wrote:How did you go with this Willie as i am having the same problem with my brumby
It has 4 wheel disc brakes and a new master cylinder and the booster is holding vacum but the brakes are dredfull so i am following your post with interest
Jeff

Just to answer Jeff / provide some feedback ......

The brake shop swapped over the check (one way) valve and tested system. He was worried about amount of vacuum assit the system was getting and has asked me to bring the car back when it's running better, as at that stage was still idling very high and not running 100%. Although idle problem much better, it's still not running great (see my other thread "HUUUUGE Flat spot - EA82T). The brake guy suggested that an auxillary vacuum tank could provide a fix - never heard of a Subaru requiring one of these before, however have heard of some cars running them.

I also posted a reply to Bratgeebah's thread on his brake conversions, asking some questions.

When I took the car over the pits and performed the brake test on the rolling road, the front brakes were OK, however I only just got over the minimum level for the rears - standing on the brakes as hard as I could! This is where my concern on the proportioning valve comes from (Ref question on Bratgeebah's thread.)

As the wagon is running a WRX master cylinder and standard booster, plus standard everything else, I am worried that the wrong proportioning valve is in the car. It was converted from rear drums to rear discs, so this could be a possibility. Additionally, if WRX's had the proportioning valve in the Master Cylinder, I could be running 2 - something I need to check. If anyone knows what set WRX's run in relation to porportioning valves, please let me know!

So, to wrap up - the brakes are still pretty ordinary and cause is unknown. When I get time, I will investigate. Until then, the car doesn't move much and I'm getting more frustrated.

Cheers,

Thanks Willie
I am running standard booster and master cylinder[new stainless steel sleeved ] with standard brumby vented front brakes and L series rear discs so my problem may not be the same as yours but the brakes sure are bad
Jeff