Page 1 of 1

Vacuum advance not returning when no suction

Posted: 25 Sep 2011, 08:54
by mblake4u
Hi All,

I think I've got a problem with my vacuum advance (on 1.9l 1984).

The diaphragm inside the vacuum advance works, i.e. it moves the lever and there aren't any hole in the diaphragm.

When I suck on the pipe to create a vacuum it moves the hall sender, but when I stop sucking the diaphragm and hall sender don't remove to their original position. This makes me think that once I've started the van and the suction has been created and the hall sender has been advanced it's going to stay that way - it's not going to retard again.

Should there be a spring or something in the hall sender unit to make it return to its original position?

Thanks in advance, Michael

IMAG0179a.JPG
IMAG0180a.JPG
IMAG0181a.JPG

Re: Vacuum advance not returning when no suction

Posted: 25 Sep 2011, 09:01
by Red Westie
As far as I was aware the 'return' spring is in the vacuum advance unit itself.
The base plate bearing/mechanism might be seizing?

Martin

Re: Vacuum advance not returning when no suction

Posted: 25 Sep 2011, 09:09
by mblake4u
Hi Martin,

Thanks for the reply. The base plate and the upper section of the sender move freely, no sticking or anything like that. OK, maybe a second replacement vacuum unit is in order!

Cheers, Michael

Re: Vacuum advance not returning when no suction

Posted: 25 Sep 2011, 09:11
by Red Westie
I take it that this is a single vac type (pipe on one side only) ? then the pull rod should return by itself and with some force.

Martin

Re: Vacuum advance not returning when no suction

Posted: 25 Sep 2011, 09:19
by mblake4u
Yes it's the single pipe unit. Thanks for the confirmation, I guess another unit is in order..

Cheers, Michael