Vacuum Diagram 318
Posted July 21, 2006 at 11:10 am
One have to go to the choke diaphragm
The second has to go to the PCV valve
And the third has to go to the exhaust manifold.
But my car originally came with a vacuum advance distributor
But some people here at Allpar told me there should not be any vacuum present at idle to the vacuum advance canister, so I have to take a hose that is connected under the throttle valve, this way there won't be any vacuum
But only the PCV valve hose is connected under the throttle valve.
The previous owner, or at least, my car came with the vacuum advance connected to a T-fitting in the hose that connects frop above the throttle valve to the choke diaphragm
Supposed the previous owner (he's dead now, I can't ask him ) screwed my vacuum diagram, can someone tell me exactly what to connect where?
as soon as I plug back my vacuum advance hose, the ignition timing goes from 4 BTDC to... 12-13 BTDC... at idle in neutral.....
Posted July 21, 2006 at 01:14 pm
Posted July 21, 2006 at 01:47 pm
Posted July 21, 2006 at 05:45 pm
Is the BBD you're using original?
An older-style BBD designed for cars with vacuum advance distributors will always have a small-diameter nipple-fitting on the right side about halfway up the throat of the right barrel. This is for the distributor.
Unless it's broken-off it should be obvious. Look again.
If for some reason you have a BBD designed for a Lean Burn System, then it will NOT have a distributor port. However some models had another fitting above the throttle plate, used for the EGR or Canister purge. These were sometimes located at the rear of the carb. You can probably tap into one of those lines with a plastic "tee" to run the distributor.
If you have no fitting, or it's broken-off, take it to a carb shop, they can re-install, or tap & affix a distributor nipple for you. This is something you dont want to do yourself, cause the fitting may fall-out, leaving a vacuum leak and no active advance.
Posted July 21, 2006 at 10:58 pm
Posted July 22, 2006 at 10:05 am
really? I will take a look at this. I had the confirmation my vacuum hoses setting were not original: the previous owner is the one that put a T-fitting at the choke hose, but when I rebuilded the carb, I just still tought it was original. Actually, his son is still alive and I called him. But he never knew why his dad did this!
According to the manual I looked up. You should have a fitting on your carb that is on the right hand side about choke diaphram height and slightly forward of the choke shaft. There should be a round boss that it comes out from. AND it is taken above the throttle plates on yours.
Thanks a lot guys for your helpful help
Edited by jaguarxj88, July 22, 2006 at 10:06 am.