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coils and tachos

Posted: 28 Feb 2009, 17:52
by Ray
Where is the vacuum take off for the diff locks on a 2.1 , is it the same as the servo? been looking for vac leaks but haven't found the origin yet.
Also is a grey label coil the same as a green label one cos just changed mine with gsf bosch one and the tacho doesn' work now. Got dark so couldn't check continuity of connections tonight - they are on the right way though. hope the tachos not burgered though.

Re: coils and tachos

Posted: 28 Feb 2009, 20:10
by Aidan
vacuum for syncro is taken off the front to back pipe just in front of rear cross member and via one way valve and reservoir set up via small black pipe to dash switches and thence to vac units
coils are different, have different secondary resistance, I guess that means different spark character. According to etka vw used different plugs with the different coils and it's by chassis number !as to which coil was fitted. As to which coil is which I'm not sure, iirc green was correct for a 86 DG 1.9 which is pretty much every thing from 85 on but I may be wrong. The spare I have on the shelf is green I think, I'd have to check the values.

Re: coils and tachos

Posted: 01 Mar 2009, 16:07
by Ray
aidan , thanks for the reply. Found vacuum pipe route OK. the rear works fine the light comes on as it should but front I have never been able to engage. The light flashes but thats all I will have to see if the rod is stuck. Does the front one flash if partially engaged? the rear one is just on or off. Fixed the tacho, I was looking at earlier bentley wiring which was changed later after 87.

Re: coils and tachos

Posted: 01 Mar 2009, 23:33
by Aidan
the front light flashes to tell you you have selected front diff lock but the actuator hasn't yet done it's job, often the flasher circuit dies so you don't get the flash but either way the light goes solid when the pin has moved far enough to move the telltellswitch if that's working and connected of course.