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ncpetersc · 08-09-2018, 07:12 PM

Back again.. and as confused as ever. (You sick of me yet?)

So I decided to try to "tune" again. About all I did since installing the new (rebuilt) carb was lean (turn in) the idle about half a turn.

Today I decided to start with the distributor first. I warmed the engine up, then turned it to find where it ran well. I have been at 12deg pretty much since my ordeal began, based on advice here which helped immensely.

Anyway, I start advancing it further and the engine likes it, rpms up vac up a little too. I got all the way to 26deg when I stopped turning and checked it! This doesn't make sense based on what I have read. Vac was up to about 23-24inches. RPM had risen to about 850. Because it didn't seem right I thought the mechanical might have kicked in, nope. Then I noticed I forgot to disconnect distributor vac. Well I did and plugged it, still nope.

My distributor vac I have never seen kick in, I think because it is either ported vac, or through the TCS solenoid or both.

Anyway, I backed it off a little, leaving it at 22deg advance, giving 20 inches vacuum, and adjusted idle to about 690 rpm.

I then leaned idle by another half a turn, and readjusted idle to about 690rpm, vacuum was still good.

I went another half and vac started bouncing 18-20, so I backed that out.

I am now probably one full turn in on the idle screws vs. when I got it from the remanufacturer.

It seems to be running well, and respond well to throttle.

Seems okay from readings, but what is with the severe advance (I think) of 22 degrees?

I am about to take it for a test drive, but would love to hear your thoughts.

Thanks!

08-09-2018, 07:12 PM	#205
ncpetersc Registered User Join Date: Jun 2018 Location: Fuquay-Varina, NC (Just outside of Raleigh) Posts: 237	Re: Help a NOOB - A continuing saga Back again.. and as confused as ever. (You sick of me yet?) So I decided to try to "tune" again. About all I did since installing the new (rebuilt) carb was lean (turn in) the idle about half a turn. Today I decided to start with the distributor first. I warmed the engine up, then turned it to find where it ran well. I have been at 12deg pretty much since my ordeal began, based on advice here which helped immensely. Anyway, I start advancing it further and the engine likes it, rpms up vac up a little too. I got all the way to 26deg when I stopped turning and checked it! This doesn't make sense based on what I have read. Vac was up to about 23-24inches. RPM had risen to about 850. Because it didn't seem right I thought the mechanical might have kicked in, nope. Then I noticed I forgot to disconnect distributor vac. Well I did and plugged it, still nope. My distributor vac I have never seen kick in, I think because it is either ported vac, or through the TCS solenoid or both. Anyway, I backed it off a little, leaving it at 22deg advance, giving 20 inches vacuum, and adjusted idle to about 690 rpm. I then leaned idle by another half a turn, and readjusted idle to about 690rpm, vacuum was still good. I went another half and vac started bouncing 18-20, so I backed that out. I am now probably one full turn in on the idle screws vs. when I got it from the remanufacturer. It seems to be running well, and respond well to throttle. Seems okay from readings, but what is with the severe advance (I think) of 22 degrees? I am about to take it for a test drive, but would love to hear your thoughts. Thanks!