anyone wanna do me a huge favor?

[BillyWagoneer]

and plug there vac advance tube into a vac gauge and tell me what your reading or if you know what your supposed to be reading?

[Rich88]

Originally Posted by BillyWagoneer

and plug there vac advance tube into a vac gauge and tell me what your reading or if you know what your supposed to be reading?

If you're talking about the vacuum at the hose going to the distributor advance diaphragm and at idle, you'll get -0- if its ported vacuum and anywhere from 15" to 19" if its manifold vacuum, depending on the health of the engine, vacuum leaks (if any) and altitude. For this reason you'll get all kinds of different answers.

[Beach_Dude]

Originally Posted by BillyWagoneer

and plug there vac advance tube into a vac gauge and tell me what your reading or if you know what your supposed to be reading?

As Rich said, it's a ported vacuum from your manifold. If you should read the same as everywhere else. Have you done a vacuum test yet anyhow, and what are your readings?

[BillyWagoneer]

well thats weird. i get a reading of about 9 on my vacum advance line. there is a nipple on the manifold itself wich you plug a line that comed of the air filter into. when i plug my vacum gauge into that i get a reading of about 19. any other places i can plug into to see if im getting a good reading? and also if my vac advance line is only getting 9 in. of vacum then i have a leak somewhere?

[serehill]

Originally Posted by BillyWagoneer

well thats weird. i get a reading of about 9 on my vacum advance line. there is a nipple on the manifold itself wich you plug a line that comed of the air filter into. when i plug my vacum gauge into that i get a reading of about 19. any other places i can plug into to see if im getting a good reading? and also if my vac advance line is only getting 9 in. of vacum then i have a leak somewhere?

This is about normal & there is a difference because one is ported & one is not. I don't agree is should be zero ported but it should be lower substantialy than non ported. Mine is about 17 non ported & I think about 6 ported.

[Rich88]

Originally Posted by BillyWagoneer

well thats weird. i get a reading of about 9 on my vacum advance line. there is a nipple on the manifold itself wich you plug a line that comed of the air filter into. when i plug my vacum gauge into that i get a reading of about 19. any other places i can plug into to see if im getting a good reading? and also if my vac advance line is only getting 9 in. of vacum then i have a leak somewhere?

In my previous post (#2) I said you could expect -0- vacuum if you are using ported vacuum for the distributor. And ported vacuum comes from the carb, not the manifold.

Since I'm set up to use manifold vacuum for many years for my distributor, I forgot if ported is 0 at idle or if you should get some low reading. Apparently I was wrong, and as Serehill suggests you should get something. Sorry 'bout that.

Otherwise your reading of 19 at manifold vacuum is good...for manifold.

[Carnuck]

Near zero at idle with the choke off.

[lil jeep mec]

im getting 16 from the manifold on mine :/ common reasons other than unplugged vac lines?

sorry not trying to take over the thread!

[710 Burner]

If you have the HDCooling system with two CTO valves and an LNR valve controlling the vacuum to the distributor, Yes you will get about 9" at idle... and you can expect all of those valves to be leaking vacuum.