brake servo
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brake servo
hi all how do i check for air leaks on the servo pipe that fits onto inlet manafold ??
1981 t25 devon 1600 ct
- sarran1955
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Re: brake servo
Hello,
Servo flexy pipe....
From the inlet manifold through the (probably gungy brown and brittle) plastic pipe to the one way valve (2 colour plastic)..
If all is well the brakes should be solid feeling when on, with not much pedal travel..
Try this test.. on the flat in neutral.. handbrake off.. engine on.. brakes on.. switch off engine..
If after 3 or so seconds you can feel the pedal pushing up for 3 or so seconds .. then all is well and the system is airtight..
Hope this helps..
Cordialement..

Servo flexy pipe....
From the inlet manifold through the (probably gungy brown and brittle) plastic pipe to the one way valve (2 colour plastic)..

If all is well the brakes should be solid feeling when on, with not much pedal travel..
Try this test.. on the flat in neutral.. handbrake off.. engine on.. brakes on.. switch off engine..
If after 3 or so seconds you can feel the pedal pushing up for 3 or so seconds .. then all is well and the system is airtight..

Hope this helps..
Cordialement..


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Re: brake servo
thank you im geeting thier cured air leaks on inlet manafold rubber joinings and a gasket thanks for servo hose leak test but better do it in daylightsarran1955 wrote:Hello,
Servo flexy pipe....
From the inlet manifold through the (probably gungy brown and brittle) plastic pipe to the one way valve (2 colour plastic)..![]()
If all is well the brakes should be solid feeling when on, with not much pedal travel..
Try this test.. on the flat in neutral.. handbrake off.. engine on.. brakes on.. switch off engine..
If after 3 or so seconds you can feel the pedal pushing up for 3 or so seconds .. then all is well and the system is airtight..![]()
Hope this helps..
Cordialement..

1981 t25 devon 1600 ct
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Re: brake servo
Accepted standard test:
1) Engine off: pump the brake pedal several times until the pedal goes hard
2) Rest you foot on the brake pedal (medium to light pressure)
3) Start the engine and you should feel the brake pedal surge downwards/gaining a degree of spongyness (from rock hard to pliable) lol
However....NOTE* if the pedal WAS hard initially and didn't need pumping to become rigid (with the engine off) this indicates a vacuum leak whilst stood, as in, hole in the supply line, faulty one way valve or damaged servo itself.
Martin
1) Engine off: pump the brake pedal several times until the pedal goes hard
2) Rest you foot on the brake pedal (medium to light pressure)
3) Start the engine and you should feel the brake pedal surge downwards/gaining a degree of spongyness (from rock hard to pliable) lol
However....NOTE* if the pedal WAS hard initially and didn't need pumping to become rigid (with the engine off) this indicates a vacuum leak whilst stood, as in, hole in the supply line, faulty one way valve or damaged servo itself.
Martin
1989 California 2.1MV
- Aidan
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Re: brake servo
test for leak
with engine running spray carb cleaner or similar onto the rbber hose, if revs increase it is leaking
usually shows as high hc when co bob on or low
with engine running spray carb cleaner or similar onto the rbber hose, if revs increase it is leaking
usually shows as high hc when co bob on or low
- kevtherev
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Re: brake servo
I filled my servo hose with parafin.. it bled like a snake blasted with buck shot
AGG 2.0L 8V. (Golf GTi MkIII)
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Re: brake servo
thank guys for the pointers it looks like i have a fault so starting with a new non return valve
£15 and a lenght of 13mm hose at manafold
end i will let you know how goes it
got a new earth strap chassis to gearbox to fit old one is very crusty

end i will let you know how goes it

1981 t25 devon 1600 ct
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Re: brake servo
SILVERFOX2013 wrote:thank guys for the pointers it looks like i have a fault so starting with a new non return valve£15 and a lenght of 13mm hose at manafold
end i will let you know how goes itgot a new earth strap chassis to gearbox to fit old one is very crusty
Vacuum hose......otherwise it might collapse.
Martin
1989 California 2.1MV
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Re: brake servo
ok iv got valve and 500mm 13hose coming from just campers hose was listed as servo hose hope it is 

1981 t25 devon 1600 ct
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Re: brake servo
update fitted new hose&clamps new return valve i now have vacum asisted brakes & no leaks on intake manafold thanks for all help given 

1981 t25 devon 1600 ct