Brake Servo and Engine Hoses Help

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Bounce

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Hi Guys,

Just getting my new 1971 Westy ready for her MOT pre-registration, and Ive a few bits and bobs missing from the engine bay, clips and hoses mostly.

I need advice as to what goes where please.



So, red is the Servo Vac hose, dose this go to the carb take off in yellow, or the manifold take off in green? Which ever one it doesnt come off, what comes off that one?



Im guessing this is for pre-heating going to the lower intake to the oil bath?



On this one, yellow goes to the carbon canister, should this go to the oil breather in blue? Or should there be a hose between the oil breather and the port on the oil bath in green?

Thanks for your help
 
Yes you are right, the brake servo hose connects to the manifold below the carb and the warm air pickup for the air cleaner goes down through the hole in the tinware where there should be a metal spout thing to connect the tube to.

It's hard to tell from your photo - does your distributor have a vac canister with two pipes or only one? The one facing you, pointing upwards, connects to the left side of the carb. If there is a second pipe from behind the vac can then this connects to the tube higher up on the carb pointing straight at you.

With both vac ports connected the timing is set, with hoses on, at tickover to be 5 After TDC.

If the hose off the back of the canister, going to the upper facing connection on the carb, is not connected then that connection should be left open on the vac can but blocked off on the carb. The timing is then set to 7.5 Before TDC. (a common modification to get rid of flat spots and improve responsiveness and mpg).

The charcoal canister used to T into the upper facing connection on the carb but I would not bother reconnecting it, since it was probably disconnected due to old age leaks.

There's a diagram here that may help you :-

http://www.justkampers.com/forum/viewtopic.php?f=15&t=159399&p=2237607&hilit=vacuum+hose" onclick="window.open(this.href);return false;

(But it's for a later type air cleaner)

The oil breather just goes straight from blue to green on your photo.
 
Thanks for the great info Trikky.

I have removed the charcoal canister and used the hose from it for my oil breather hose.

I have a couple of queries though.

The hose from the servo has an internal diameter of 8mm (I even cut it back an inch incase it had been flared out), and the bit of blocked-off hose that was on the manifold vac port has an ID of 6mm. The non-return valve supplied by VW Heritage takes 12mm hose, and they supply 12mm hose for the section I'm looking at. Has my hose been replaced at some point maybe? Or am i looking at the wrong part?

My dissy vac capsule has only one port. Should my timing be set to -7.5 or +5?

The pre-heat hose has nothing to connect to through the tinware, all I can see is the exhaust back box. Am I missing something?

Many thanks
 
Bounce said:
Thanks for the great info Trikky.

I have removed the charcoal canister and used the hose from it for my oil breather hose.

I have a couple of queries though.

The hose from the servo has an internal diameter of 8mm (I even cut it back an inch incase it had been flared out), and the bit of blocked-off hose that was on the manifold vac port has an ID of 6mm. The non-return valve supplied by VW Heritage takes 12mm hose, and they supply 12mm hose for the section I'm looking at. Has my hose been replaced at some point maybe? Or am i looking at the wrong part?

My dissy vac capsule has only one port. Should my timing be set to -7.5 or +5?

The pre-heat hose has nothing to connect to through the tinware, all I can see is the exhaust back box. Am I missing something?

Many thanks

Your servo hose attachment point would normally be larger. It sounds like the manifold you have has the port used in the emissions limiting system for California spec engines. Those small ports are normally capped off on non cali engines.

The inlet manifold for servo has a pipe in the same place but its about 10/12mm diameter. I don't know but doubt will work. You could try connecting it with a sleeve to compensate for the difference in diameter. If it doesent work (and your sure the servo is in good order) then the only thing you can do is either change the centre section of the manifold or have your current one drilled and a larger pipe welded on. Either way it would need to come off.

You will need to get the servo working because the master cylinder is different to a manual one. By that I mean that manual brakes are quite heavy but a not connected servo master cylinder will result in very heavy brakes indeed (its a larger diameter and requires al lot more pressure).

With a single vac canister your timing should be 7.5 degrees Before top dead centre. The hose should be connected to the carb port on the left. The carb port facing you should be blocked off.

For the pre heat pipe, yes your missing a tin spout that attaches by one screw on the tinware. It will still work with just the pipe - just not as well as it could.
 

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