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Old 08-19-2018, 12:42 PM   #246
ncpetersc
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Join Date: Jun 2018
Location: Fuquay-Varina, NC (Just outside of Raleigh)
Posts: 237
Re: Help a NOOB - A continuing saga

Quote:
Originally Posted by 68 P.O.S. View Post
Why do you still have the TCS connected, and does it actually work still?? If it works, and correctly, it's not allowing the vac advance to come in just yet as designed. I would disconnect it and remove the wiring; it was an early, crude emissions thing and it provides no benefit to your engine and only stops your vac advance from working correctly. The only people who really still use the TCS are those doing a factory correct restore, or they just don't understand the TCS. Plug your vac advance can directly to manifold vac and you should see the idle increase. If not, you have a bad vac can. Now you need to find out how many degrees of advance your vac can provides. You want it to be around 10 degrees, or you'll probably get pinging if it has more than that.
After staring at the motor for a while and considered my options, I decided I wasn't going to be able to manually turn the thing without taking too much apart. So instead I decided to see what I could figure out just using the starter.

I pulled the coil wire from the distributor and pulled the #1 plug. It didn't take a whole lot of tries to get it to hit +4 and 0 degrees on the marking tab. Both of these positions the piston seemed to be TDC to me, could touch it with a screwdriver just inside the plug whole. Since the ring on the balancer slipping seemed a little less likely (though possible I am sure) I decided to go ahead and assume my balancer mark is fine, and has not slipped.

Call me lazy, I'll agree with you, and I'll just hope it's a safe assumption for now.

So, then I was going to try to take the TCS business out of the picture. But before I did I set the "initial" back down to 10deg or so, expecting the 22deg could be too much with vacuum advance about to be added. I initially just bypassed the solenoid but observed no additional vacuum. It turns out that I was set up with a "ported" vacuum port and the TCS solenoid.

I switched to using a manifold vac port, as suggested. My vac advance gives about 20 degrees it turns out. My dist must have moved a bit (it wasn't tightened yet) but I had 9 BTDC with the vacuum disconnected and 29 with it connected. Does this sound alright? I know 10 deg vac advance was mentioned, but I have certainly heard from others that they have around 20deg.

So I am currently thinking that it is very likely that I never had any vacuum advance before, and the TCS solenoid didn't function.

I rev'd up the engine and observed a total of about 52 degrees timing. I hope this is all in but I really hate rev'ing it that high under the hood for some reason, so I might have chickened out a little. I probably observed it about 3000rpm at least.

So now that I am on full manifold vacuum, I'm trying to figure out proper next steps. It seems like you can get varying opinions on this subject, and that's fine, just looking for ideas.

Personally, I have been convinced by some things I read that using a vacuum gauge to time and to tune the idle circuit is a good way. But I am not knowledgeable, maybe just gullible.

What's that definitive way to time and adjust idle to perfection?

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