The Stovebolt Site Forums The Shop Area Engine Shop 283 Vacuum Lines

HI! I have a 1964, 283 that is going in my 51, 3600. I have power brakes in the truck that require a vacuum line and the engine has a PVC valve that also requires a vacuum line. These line are approx 3/8" in diameter. My two barrel carb has a 3/8" fitting in the base, in the back of the carb. The two large vacuum lines seem quite a bit to run into this one fitting. How about suggestions as to how to make this situation work?!

just get a brass fitting with 2 outlets and hook'em up, that outlet in the carb base is engine vacuum, not ported .... and make sure that original style pvc is working right, they plug up with age

Bill

And remember the line to the booster must have a check valve in it so booster vacuum does't fluctuate with manifold vacuum.Most times it's in the angle fitting that plugs the line into the booster body but some older boosters didn't do it this way.

Hi engine nut, one of the fittings I found in the "junque" drawer has what appears to be a restrictor of some sort. The hole in the fitting is necked down to a tiny hole about the size of a #55 drill bit. Does this sound like what you are talking about?

Hey Rick, No, the check valve is lately a plastic fitting at the hose to booster chamber connection and when you test it with oral vacuum it will pass air away from the booster but not toward it.Some older boosters with a remote reservoir (usually truck or aftermarket)would have a in the line fitting which worked just as the one we described.Without this when the engine is shut down and vacuum is zero you would have no vacuum assist and panic would likely ensue although anyone MAN enough to manage a stovebolt would do OK without boost but he probably would talk ugly.
If your booster is the type which mounts the MC and has a rubber grommet where the vacuum line connects, the check valve usually plugs in this grommet.These checks do malfunction but should be readily available on the HELP board at local parts store.

Thanks enginenut. I found it, it is mounted on the booster next to the master cylinder where the vacuum line goes into the booster. Now to find the right T fitting.