AUSMHLY
Obi Wan
Offline
64 BJ8 vacuum system.
What is it's purpose and how do I test it to make sure it is working?
1. The copper vacuum pipe that connects the vacuum unit on the distributor and the vacuum advance adaptor on the rear carburetor is clean. I shot some carburetor spray through it to make sure it's not clogged.
2. The vacuum advance adaptor on the carburetor is clean also. (The Carbs were rebuilt by Joe Curto a couple years ago.)
3. The rubber hose that connects the adaptor to the vacuum pipe is clean and makes an air tight connection.
4. I don't know if the vacuum unit is working or not. How do I test that?
With the car warmed up, it idles around 850. However during driving, when sitting at an intersection, it may drop down to 550-600. Then later be at 800-850. It's not consistent.
I've checked for vacuum leaks by spraying carb cleaner on all the hoses and their connections, the inlet manifold gasket area, the check valve fitting on the manifold and the brake booster. I've sprayed all areas of the throttle shaft too. None of those area seem to have a problem, for the idle does not change, does not drop.
Why does this happen...
1. I disconnected the vacuum pipe from the vacuum advance adaptor and it made no difference in the idle. I put my finger over the pipe on the vacuum advance adaptor and it made no difference in the idle.
2. I disconnected the vacuum pipe from the vacuum unit on the distributor and it made no difference. I put my finger over the opening on the vacuum unit and it made no difference.
I'm under the impression that if a car has an uneven idle, hunts or an idle changes as the engine's temperature climbs or drops it maybe because of a vacuum leak.
Cheers,
Roger
What is it's purpose and how do I test it to make sure it is working?
1. The copper vacuum pipe that connects the vacuum unit on the distributor and the vacuum advance adaptor on the rear carburetor is clean. I shot some carburetor spray through it to make sure it's not clogged.
2. The vacuum advance adaptor on the carburetor is clean also. (The Carbs were rebuilt by Joe Curto a couple years ago.)
3. The rubber hose that connects the adaptor to the vacuum pipe is clean and makes an air tight connection.
4. I don't know if the vacuum unit is working or not. How do I test that?
With the car warmed up, it idles around 850. However during driving, when sitting at an intersection, it may drop down to 550-600. Then later be at 800-850. It's not consistent.
I've checked for vacuum leaks by spraying carb cleaner on all the hoses and their connections, the inlet manifold gasket area, the check valve fitting on the manifold and the brake booster. I've sprayed all areas of the throttle shaft too. None of those area seem to have a problem, for the idle does not change, does not drop.
Why does this happen...
1. I disconnected the vacuum pipe from the vacuum advance adaptor and it made no difference in the idle. I put my finger over the pipe on the vacuum advance adaptor and it made no difference in the idle.
2. I disconnected the vacuum pipe from the vacuum unit on the distributor and it made no difference. I put my finger over the opening on the vacuum unit and it made no difference.
I'm under the impression that if a car has an uneven idle, hunts or an idle changes as the engine's temperature climbs or drops it maybe because of a vacuum leak.
Cheers,
Roger