404 front disk calipers sticking

G

Gilow

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Fellow Frogger
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Adelaide
Second question for the brains trust:

The 404 is on the road now after sitting in the shed for a few years (3?). I notice the front calipers are sticking slightly. I am thinking of doing a seal kit on them, but before I touch anything I thought I should check if there are any gotcha's with these.

For instance, are there different sizes or models of front calipers that will mean I ordered the wrong bits?

Also, is there a recommended local supplier of the seal kits?

The car is, we think, a 1968, with front disks. From time to time I thought it was 1969 but the rego mob don't agree.

Matt
 
Update to this post... the sticking has stopped, but I still feel I should do a seal kit on the calipers, plus t replace the various hoses, so if anyone has a recommended local supplier I am keen.

Matt
 
I think the dust covers are even harder to get, bought these a couple of years ago, NOS but the rubbers were all still nice and soft, and they been running fine ever since fitted then.

20151114_111056.jpg 20151114_111152.jpg
 
Matt,

I found some locally, via a local Burson Auto Parts. See below for details. (It is an entry from my thread.)

If you have any difficulties sourcing them, drop me a line and I’ll go see the guy I deal with at my local Bursons. He is extremely helpful.


Is it the calipers binding or the booster valve sticking? If it is the booster valve sticking, history tells me it starts sticking occasionally then gets worse. It’s not a lot of fun when the front brakes lock on and won’t release. No steering while it is sliding. Last experience of this still scars my memory. Touched the brakes approaching a pedestrian crossing on a wet road, Bang locked on front brakes and slid hopelessly through the crossing with my hand firmly on the horn.... Car was towed home and not driven until the issue was found and solved.

Like yourself I’d try the calipers first. Does the car still have the original Hydrovac booster or is it a replacement aftermarket, such as a PBR.

Cheers,

Dan

Finally found a set in Brisbane. A company called PROTEX have them listed. Part number K770S. $44 a set. The aforementioned ‘O’ring is included in this kit.

 
Dano said:
Matt,

I found some locally, via a local Burson Auto Parts. See below for details. (It is an entry from my thread.)

If you have any difficulties sourcing them, drop me a line and I’ll go see the guy I deal with at my local Bursons. He is extremely helpful.


Is it the calipers binding or the booster valve sticking? If it is the booster valve sticking, history tells me it starts sticking occasionally then gets worse. It’s not a lot of fun when the front brakes lock on and won’t release. No steering while it is sliding. Last experience of this still scars my memory. Touched the brakes approaching a pedestrian crossing on a wet road, Bang locked on front brakes and slid hopelessly through the crossing with my hand firmly on the horn.... Car was towed home and not driven until the issue was found and solved.

Like yourself I’d try the calipers first. Does the car still have the original Hydrovac booster or is it a replacement aftermarket, such as a PBR.

Cheers,

Dan

Finally found a set in Brisbane. A company called PROTEX have them listed. Part number K770S. $44 a set. The aforementioned ‘O’ring is included in this kit.
Click to expand...

Thank you Dano, I will check them out. Definately the calipers were sticking, freed them up with a bit of gentle back and forth and they are behaving now, but I don't trust them so I will chase up your leads.

Matt
 
Dano said:



Is it the calipers binding or the booster valve sticking? If it is the booster valve sticking, history tells me it starts sticking occasionally then gets worse. It’s not a lot of fun when the front brakes lock on and won’t release. No steering while it is sliding. Last experience of this still scars my memory. Touched the brakes approaching a pedestrian crossing on a wet road, Bang locked on front brakes and slid hopelessly through the crossing with my hand firmly on the horn.... Car was towed home and not driven until the issue was found and solved.

Like yourself I’d try the calipers first. Does the car still have the original Hydrovac booster or is it a replacement aftermarket, such as a PBR.
Click to expand...

I think it has a reconditioned booster, looking at the service receipts (some HORRIBLE numbers in there), not sure if it is hydrovac or aftermarket. But I have also purchased a recently reconditioned unit from a wonderful Peugeot enthusiast here in Adelaide so I've got options.

But your caliper seals lead is gold, thank you, I will get on the phone to them tomorrow.

Matt

P.S. Bloody glad to hear you survived the brake issue, and I have always remarked that one of the easiest controls to find and operate in any French car is the horn. Having stood in the Paris at the Arc De Triomphe, I can understand why.
 
Dano said:
Matt,

I found some locally, via a local Burson Auto Parts. See below for details. (It is an entry from my thread.)

If you have any difficulties sourcing them, drop me a line and I’ll go see the guy I deal with at my local Bursons. He is extremely helpful.


Is it the calipers binding or the booster valve sticking? If it is the booster valve sticking, history tells me it starts sticking occasionally then gets worse. It’s not a lot of fun when the front brakes lock on and won’t release. No steering while it is sliding. Last experience of this still scars my memory. Touched the brakes approaching a pedestrian crossing on a wet road, Bang locked on front brakes and slid hopelessly through the crossing with my hand firmly on the horn.... Car was towed home and not driven until the issue was found and solved.

Like yourself I’d try the calipers first. Does the car still have the original Hydrovac booster or is it a replacement aftermarket, such as a PBR.

Cheers,

Dan

Finally found a set in Brisbane. A company called PROTEX have them listed. Part number K770S. $44 a set. The aforementioned ‘O’ring is included in this kit.

Click to expand...

Dano,
Further to your frightening "Hydrovac locked brakes" experience, I had a similar/ different locked brakes occurence....a big brake on busy country road...locked brakes at night middle of the road...eventually cracked open the hydrovac brake hose to release the pressure...that allowed the car to be moved.

It would seem that this is to do with crud in the bore locking the Hydrovac piston in a 'heavy braking' situation. Maybe the VH40 replacement is less prone to this problem due to an alloy bore?

Cheers

John
 
Edited: I was confusing the non-return vacuum valve with the residual pressure valve.

I think in all cases of Hydrovac cars, the residual pressure valve is in the hydraulic circuit at the slave cylinder of the booster, as in this image:
46321810561_01dfa0fd89_b.jpg


The thing I wrote about first was the non-return valve in the vacuum tubing, which doesn't exist in RHD cars. It's seen here (in the vacuum tubing):
46321811031_c718954c8b_b.jpg


When the residual pressure valve sticks on, releasing the vacuum suddenly at an air union can reseat it. But if it's sticking, there really is a hydraulic problem with the function.
 
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