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mrtwisty

Member

Registered: 2021-07-08

Posts: 1

Dispatch brake issue - very limited vac assistance

Hello folks

2005 Dispatch, 1.9d (non-turbo) - DW8B I believe?

I have an odd issue, as above - the brakes are only assisted for one quick use of the brakes, then the pedal goes hard. Oddly it's worse with a light application of the brakes - a hard application results in some decent brake force for a longer period (briefly!)

Vacuum assistance soon returns when you come off the brakes and give it some revs, but then gone again just as quickly the next time you use them.

I've only just bought the van and there appears to be fairly new vaccum pump (which I've had off and checked - fresh seals, new pipework, unworn cam pegs). 

What should I be looking at next? Servo?

Last edited by mrtwisty (2021-07-09 16:12:22)

AlvyLad

Member

Registered: 2021-06-11

Posts: 481

Re: Dispatch brake issue - very limited vac assistance

not an answer, same problem "working" on- asking peeps here
#41 onwards 2021-06-11 18:51:29
https://dispatchexpertscudo.org.uk/foru … id=715&p=2

Stu-D

Member

From: Scotland

Registered: 2019-07-30

Posts: 168

Website

Re: Dispatch brake issue - very limited vac assistance

Hmmm do you get any juddering like its ABS at all, or similar? I used to get that until I deleted the ABS lol, but yeah, if it is vaccum related surely you would be able to do a leak test from the master cylinder and/or follow where that connects to? It's been a while since I looked at the brakes on mines and there's n way I'm getting out with a LED light at this time the midgies will eat me alive lol.

My egr is deleted/ relevant vac's are blocked, so that may me worth looking into and or replacing any of the hosing.

-Stu

Last edited by Stu-D (2021-07-16 01:14:24)

AlvyLad

Member

Registered: 2021-06-11

Posts: 481

Re: Dispatch brake issue - very limited vac assistance

@mrtwisty
got mine "fixed"
Replaced vacuum pump unnecessarily, got 2 spare EGR's
Blocked some of the pipes (eliminating EGR) brakes worked, later didn't, ended blocking all pipes with ball bearings, but the one that goes to servo... didn't work.... next day- brakes are fine, no warning lights etc.

Went back to mechanic for a chat now, he goes: "your pump (both) or either should've had some sort of valve bearing, that gets stuck or you had a vacuum leak somewhere, that's intermittent. All works now, shall not bother doing anything else"

find a ball bearing (6mm) stick it inside the pipe (2)...

should solve all or many issues, solved my brake inefficiency question

Last edited by AlvyLad (2021-07-26 18:32:51)