distributor vac advance help plz

[mickeyflyn]

On my df engine the distributor vac advance unit has a small rubber hose about 2 inches long with a screw in the end blanking it off . What is this tube for and why would it be blanked off ?
I have renewed all the vac pipes in the engine bay and this blanked off one is annoying me as to the reason for it .

[bigherb]

The distributor should have two vac pipes, advance connected to the side of the carb and the retard connected to the front of the carb, Really need a picture to see why someone has blanked it off.

[mickeyflyn]

I will take a pic and post it in the am.

[mickeyflyn]

URL=http://s40.photobucket.com/user/mickeyf ... 6.jpg.html][/URL]ere is a photo of the pipe that has been blanked off on the distributor . Does anyone know what it's for and why it may have been blanked off ?

[CovKid]

Those type were often found on earlier engines (even bays and bugs). Could be that the vac unit was fitted after original packed up, or its wrong dizzy (not uncommon) although if engine runs fine, don't worry about it.

[mickeyflyn]

It was running lumpy,since I renewed all the vac pipes and new plugs etc it's ok apart from it ticks over at very low rev when warm. i don't know how to turn tick over up a fraction.

[bigherb]

That is the retard vacuum blanked off which should be connected to the front of the carburettor.
If it is not connected then if the timing needs to be adjusted it will need to be at 7.5 deg BTDC, not at the timing mark which is 5 deg ATDC.
They are sometimes disconnected if a different carburettor is fitted it should be then left open not blanked off.
Have you a picture of the carburettor and how the vac pipes are connected? We might see why it has been disconnected.

[mickeyflyn]

Hi BH I was working on the engine and carb today the carb fitted is a pierberg 2e and according to tech it should be a sole 34 pict so at some point it's been changed.
If as you say it's the retard vac pipe and it should be open I will do this tomorrow . I did have a good look around the 2e carb today and found no other point where a vac pipe would go. I have just changed all vac pipes .

[bigherb]

That explains it the Pierburg is a replacement, originally it would have had a Solex 34 PICT carb using your double vacuum advance and retard distributor. The Pierburg carb use a single vacuum advance only distributor. Hence your retard vacuum hose is disconnected.

[mickeyflyn]

Thanks for the advice BH I'm learning all the time and hopfully in the near future I will be able to pass the knowledge gained to other new members . The knowledge here is second to none and i very much appreciate the help

Mike