Bleeding rear drums (1 Viewer)

[fullthrottle]

Well, well well.
After pondering this for some time, trying a new LSPV and finally deciding not to give up. I found the bloody problem.

I'll let you see if you can spot it.....

 

[fullthrottle]

Another little clue you say??

 

[sodafeld1]

pvo was a knob. really consider that bad practice and/ or advice if any knob recommends to crush close any hydraulic tube. ..the idiots really are everywhere including the past.
Guess it is an appropriate technique if you go ahead with the bullbar idea

 

[Rigster]

Well, well well.
After pondering this for some time, trying a new LSPV and finally deciding not to give up. I found the bloody problem.

I'll let you see if you can spot it.....

View attachment 3849016

WTF???

That's some really good troubleshooting and masterful fix right there done by some PO...

Good find!

 

[bj70bc]

classic....

 

[lacalvette]

I don't get it, the PO probably installed the plier because a bad rear wheel cylinder (let say). My limited knowledge of the lspv tell me that loosing pressure on the rear brake circuit, the "differential" spring would send oil from front to rear.
After the hypothsys repair on the rear, if the lspv v/v worked properly, there should be some brake on the rear wheel, comming from front circuitry?

 

[Felde]

My limited knowledge of the lspv tell me that loosing pressure on the rear brake circuit, the "differential" spring would send oil from front to rear.
After the hypothsys repair on the rear, if the lspv v/v worked properly, there should be some brake on the rear wheel, comming from front circuitry?

That's not how the LSPV works. It's actually the other way around: it starts with full brake power in the rear and , when actuated, the LSPV sends brake power from the rear back to the front.
In your scenario, it wouldn't actually matter if the fluid would actuate a proper brake cylinder correctly, or just leak out of a faulty one. Only the amount of fluid being available in the rear would differ dynamically as per the LSPVs dynamic action. The interesting part would be when letting off the brakes and air might get sucked in: How much air and where would it go?
Anyways, that's all theories only.
As a fact: No brake system (with or without LSPV) can work properly if half way clamped off.

 

[JuanJ]

That's not how the LSPV works. It's actually the other way around: it starts with full brake power in the rear and , when actuated, the LSPV sends brake power from the rear back to the front.
In your scenario, it wouldn't actually matter if the fluid would actuate a proper brake cylinder correctly, or just leak out of a faulty one. Only the amount of fluid being available in the rear would differ dynamically as per the LSPVs dynamic action. The interesting part would be when letting off the brakes and air might get sucked in: How much air and where would it go?
Anyways, that's all theories only.
As a fact: No brake system (with or without LSPV) can work properly if half way clamped off.

Hello.

That is a good description of how it works.

There are those who believe clamping off part of the system increases the pressure on the braking elements. It is a little more complicated than that.






Juan

 

[sodafeld1]

I just don't like the idea of crushing a hose which is not meant to be crushed. Fairly common practice on a youtubby.

 

[JuanJ]

I just don't like the idea of crushing a hose which is not meant to be crushed. Fairly common practice on a youtubby.

Hello,

Neither do I.

There are those youtubbies who know what they are doing, and they are those who do not. Details like hose crushing help to tell the former from the latter.

Interestingly, brake cylinders give up the ghost well before the LSPV does. At least that is my experience. However, different operation conditions lead to different wear and tear effects.





Juan