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billjam billjam is offline
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Join Date: Aug 2007
Location: Perth, Western Australia
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Bump - I am getting closer to putting this engine back together and I still really didn't identify if my vacuum unit is stuffed or not ....
Originally Posted by billjam View Post
While I have my motor in bits to fix some oil leaks and the clutch I thought I'd just check over my distributor and it seems that the vacuum advance/boost retard might not be working properly.
When I suck on port A, the arm pulls in and out as I would expect. It holds vacuum until I release it.
However, when I suck or blow into port B, nothing happens. There is quite a restriction to airflow but it doesn't hold vacuum or pressure - its as if it the diaphram has a small leak.
What is normal for this type of 930 distributor (1986)?

Is there anyone out there with a vacuum unit from a 930/68 motor that they can test for me?
I would like to know what happens when you blow and suck in each of the ports. On mine, port A seems to work, but pressure or vacuum at port B doesn't seem to do anything. Mind you, I was only blowing with my mouth - perhaps at boost pressure something happens?
I'd rather be sure it's stuffed before I order a new $175 part from our host.
Old 08-19-2008, 03:34 PM
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