Vacuum advance unit........

[Hedgehopper]

Would appreciate some advice on the following problem.

1) Vacuum unit is very loose, screws have been tightened but with no effect. They seem to screw into nylon/plastic plugs in the wall of the distributor body and appear to have stripped their threads. Can the plugs be replaced?

2) When sucking on the vacuum pipe there is a small movement of the link inside the distributor body, perhaps just a couple of millimetres which rotates the plate by 2 or 3 degrees or so. I expected to see more movement than this.

3) How many degrees of advance does the vacuum unit produce when working correctly?

Thanks.

[ronspeedsix]

Replaced my vacuum unit months ago and have not seen the nylon bushes. Thread is directly in the distributor body. Maybe this proof of an earlier stripping out and a fix. Guess you could do it again.

The movement of the pistonheads is way more than a few millimeters. I've not measured it but as far as I can remember it is at least 5 mm.

Does it loose it's vacuum (put on a hose, make it vacuum and bend the hose so sharp that it is closed, the piston should stay in position)? If so the membrane has gone.

Regards Ronald.

[Hedgehopper]

Thanks Ronald.....

The movement of the arm is minimal, less than the 5mm you suggest. However it does hold a vacuum so membrane not torn I guess.

Where did you buy your new unit from? There is a big variation of prices.

[ronspeedsix]

As it's holding the vacuum i don't think something's wrong.
Just went to my griff to check the amount of movement.
Removed distributor cap and looking between the rotor and the plastic cover while vacuming. Rotation at mine is just a few millimeters, so the same as you mentioned.

So I think you have a healthy unit.

BTW, bought mine at Trevor Clevor for GBP 58,= ex VAT

Ronald

[Hedgehopper]

That's a better price, have seen them over a hundred!

Thanks.