VACUUM ADVANCE

[SAP]

GOOD DAY ALL - CAN YOU ADVISE IF THE VACUUM ADVANCE IS REALLY REQUIRED HAVE BEEN TOLD MINE IS NOT WORKING AND REQUIRES REPLACING - BUT HAVE BEEN TOLD THAT IF YOU BLANK OFF AT CARB/AND REMOVE(THE VACUUM ADVANCE)THEN NO NEED TO REPLACE IS THIS CORRECT.. STEVE

[GDPR]

imported post

Not in my experience Steve- your fuel economy will suffer badly in the cruise condition and your engine won't be as sweet or powerfulat any other throttle setting than full bore - much better to have the vac advance there and working.

The distributor baseplate is also anchored by the arm of the vac unit - if you just removed the vac unit your ignition timing would wander about all over the shop......

Russ

[WildStag]

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I have just had mine replaced and the difference between before and after is very marked - most noticeable when accelerating away from a start e.g. at a junction. If you are happythat your Stag is like an amiable old Moggy when pulling away, with the phrase "couldn't pull the skin off a rice pudding" popping into mind, then leave well alone. On the other hand, since you have a 3 litre V8 up in front . . .

New units cost c £35 (one item not to buy used off e-Bay) and will take a mechanic1½ hours to fit.

[DJT]

imported post

WildStag wrote:

New units cost c £35 (one item not to buy used off e-Bay) and will take a mechanic1½ hours to fit.

One reason why mine only goes into a garage once a year for its MOT. A new vacuum advance unit should only take 1/2 an hour, including re-timing. Even one of the engine tuners at National Day changed one in about 15 minutes (or about 45 minutes if youinclude the time it took the customer to actually find one that worked among those being offered by the autojumblers as neither of the Stag parts suppliers present had brought one for sale).

Dave

[SAP]

imported post

Cheers - thanks for yr info have vacuum advance on order will replace and see if performance improves -Steve

[Malcstag]

imported post

Hi, art you sure its not working? I thought mine had gone but it was crap aftermarket pipe connector that was the cause, I tested this by sucking on a pipe connected to the vacumn advance with timing light on it worked, but full throttle nothing. I wound some black insulation round the metal outlet and inlets tubes and job done.:dude:

[toneil461]

imported post

Hi,

Is the unit faulty??? If you have contact breakers check to ensure that their securing screw have not been changed for ones that are slightly longerand checkthe washer is not missing from the screw as this willstop the base plate from moving and render the advance/retard mechanism useless...

Terry..