Hello, I want to plumb in the servo and distributor vacuum advance on my Mk1, neither are connected at the moment. It's not actually on the road as yet, no MOT, but I would like to sort this out first as the brakes could do with a bit of servo assistance and presumably it won't run quite right with no dizzy advance. The car is a 1975 1500cc auto with twin Dellorto 40's fitted to it using a non-standard manifold (all fitted by previous owner). The problem is that there doesn't appear to be a suitable vacuum take-off on the manifold or carbs anywhere. I don't really want to take it all apart to drill a new hole in the manifold, drilling it in situ would presumably drop filings into the engine. In the pic you can see that there is a little hole in the manifold (with a screw blocking it up) by cylinder number 4. This appears too small to do anything with though? Is it possible to connect the vacuum connections another way? Perhaps fit an adaptor of some kind to the carbs to connect to vacuum line to? I'm a bit thick in these matters, ask me a k-jet question instead... Pic of setup... Any ideas much appreciated! Cheers Stu Edited by: Stu
That looks to be it. Probably not drilled out just in case you only need a teeny pipe for the vacuum advance. So carbs and manifold off and drill it out. You may be able to source a take-off pipe from another VW. Not sure if they are threaded in but you can always use an epoxy to glue it in. Classic car places sell vacuum hose by the metre - and it is different - or Demon Tweeks - they may have the fitting as well. No vacuum advance on the dizzy? Barkstar
whats the casting on number 4 cyl?looks like a vacuum take off just re-read the post the casting looks like the vacuum take off point and just needs drilling out Edited by: mk1.
Ok, thanks for the advice. It looks like I'm going to have to get the manifold off then and drill it then, I wanted to avoid that if possible. Will the inlet manifold come off without disturbing the exhaust manifold, presumably that could save a bit of time and some skinned knuckles? Barkstar - the dizzy is a standard vacuum advance one, the vacuum pipe is there but just not connected to anything. I expect the car will run better once this is connected!
inlet will come right off easily, no need to disterb the zaust at all It'll run much better once you throw that chocolate block as far as you can and solder the wires properly
you need on of these for the dizzy vac advance http://www.scottoiler.co.uk/pc/viewPrd.asp?idcategory=10& ;idproduct=77
Thanks for the replies. I did try connecting a suitable rubber pipe to the existing take off point yesterday (the one with a screw in it on the pic) and there was a reasonable vacuum. I hooked it up to the brake servo and dizzy advance but there didn't appear to be any assistance on the braking. The hole that was there was tiny, just big enough to stick a small drinking straw through (the one that comes with a can of WD40) - is that too small to supply vacuum for the servo? Rubjonny - yes, there are a few wiring issues to sort!
The servo needs a proper chunky connection, its about 1cm bore I think? A tiny feed like that isn't going to be enough
Ah ha, that'll be my problem then. I'll have to get the manifold off and drill it then. I have the original manifold in the garage somewhere, I could drill it the same size as the vacuum take off on that - surely that will be just right?
