MASSIVE Vacuum Leak

[65-440]

Alright, Ive re-torqued and if I spray the base and the manifold with brake clean it doesn't seem to shoot up in RPM anymore, but it still wont idle in gear. Hoped it was my problem, but it seems not so. Probably will go back to my 2 barrel. I'm building a 383 for it anyway...

Don't go back, figure out the problem! Go back to baseline adjustments on the carb, disconnect all hoses and plug the vacuum ports on the carb. How far out are your idle mixture screws?

 

[Slap Stick]

Are you sure this carb is good? It could have an internal leak.
Dont give up yet!

 

[69SatelliteGuy]

Idle mixture is 1 turn out, running 58s. It was idling fine when it was first put on after I got it dialed in. When cold, it was idling a bit high, so I adjusted the fast idle speed and it seemed fine. Now all of a sudden though, it just wont idle in gear. Maybe I need to rebuild the carb (again). Setting it back to baseline is a start, 1.5 turns on the idle and 1 turn in on the idle screw seems like a good start, yeah?

 

[Moms68]

What is your timing set up. Vacuum advance?

 

[69SatelliteGuy]

Vacuum advance, I'll have to check, but I think it's right around TDC maybe a bit before.

 

[ckessel]

Get your timing in the 6-10* range. When setting the idle mixture of the carb, it should be done in D in the 6-700 rpm range. Also hook a vacuum gauge to it so you can set the mixture screws to the highest vacuum it will go to. Check your timing at this time too and get it in the 6-10* range in gear, vacuum advance disconnected and port on carb plugged. Also make sure the vac unit is on the correct port when its hooked back up. Of course for this you'll need a body inside stepping on the brake.

 

[69SatelliteGuy]

Alright, I'll have someone step on the brake for me. I always thought timing was in neutral, but drive works. I had an idea to start the car with it on jackstands and see if it dies then, because then Ill know if it's only dying when its got load on it.

 

[ckessel]

Sometimes I got brave and just set the e-brake. When you are young, dumb stuff happens sometimes.

 

[69SatelliteGuy]

So, I'm impatient. My buddy is coming over Saturday to help, but I messed with it a bit today. I got the distributor adjusted in the area of 5-10* before, but it goes crazy sometimes. I've got it able to run at 1700 really well, but it's a fine line between that and stalling on the idle adjust screw so I'm really at a loss. Idle mix screws are 1.5 out and vac advance is plugged.

 

[JG1966]

I always thought timing was in neutral, but drive works.

Just in case that wasn't a typo, timing is done with car in park not drive! Idle mixture screws are done with car idling in drive and someone in car stepping on brake (or by yourself with emergency brake on and wheels chocked).

 

[65-440]

If it was running fine before and all of a sudden started stalling out you might have some debris in the carb. Maybe plugged idle circuit. 1 turn out should be enough to hold an idle. We're all shooting from the hip here, hard without the car right in front of you!

 

[69SatelliteGuy]

So, would it be a bad idea to throw the 2 barrel that is adjusted well on the Holley intake to see if it's the carb or the intake? I'm thinking to pull the Holley apart and blow it out.

 

[Ron H]

Oh man, I'm too cautious I guess...no way I'd set the E-brake and put the car in gear - get the wife or a buddy to step on the dang brake for a few minutes...

 

[69a100]

Oh man, I'm too cautious I guess...no way I'd set the E-brake and put the car in gear - get the wife or a buddy to step on the dang brake for a few minutes...

I've done that, no problem. I also have a big-*** block stuffed up against the tire for backup as well.

 

[69SatelliteGuy]

I don't trust my parking brake enough...

 

[69SatelliteGuy]

So I experimented today and threw the 2 barrel Carter on the Holley intake and no vacuum leak. Must be something with the Holley. Unfortunately, when I was going threw the gears, it caught reverse and it sounded like a gunshot. I now have no coolant (?) and the engine is definitely crooked, thinking motor mounts and probably needs a u joint.

 

[Moms68]

Geez...at least you solved the idling problem.

 

[69SatelliteGuy]

Geez...at least you solved the idling problem.

I took it as a win LOL.

 

[ckessel]

Did you clean the carb and put a kit in it before installing[ if it was used]? Or did you just slap it on? Was it a new unit?

 

[69SatelliteGuy]

The carb was NOS, but from 1975ish. I did rebuild it. I put it back on tonight with a new base gasket, I haven’t checked vacuum leaks, but it doesn’t seem to want to idle less than 2000 even with the choke full open.