Tubby~ I love the photos you supply!!! No, my light is a basic Sears light, I believe. I haven't seen the video yet, but I can say I put on a new vacuum advance from our host. It seems to advance with the increase of RPMs, but it isn't much. Of course, I only went up to RPMs that you might find halfway through 2nd gear. BTW, my carb is a Rochester with only the one mixture(?) screw. The video I watched and used to rebuild my carb said that the guy would run the screw all the way in, (gently) and then back it off a turn and a half. That's where mine is set.
That's a good start for the mixture screw You really need to find out where your at timing wise. As I mentioned above you ,might have to advance or retard your distributor.. Timing on the ball is just initial timing. Further adjustments need for max vac at idel. Usually 20 inches at 450 to 500 rpm. Not sure about gmc.
That's the thing~ Since I am 180 degrees out, I'm guessing I will be on the side of the flywheel opposite of the timing marks? (Not that I'm shy about loosening the clamp and trying this, that, and the other thing.)
So even though what should be 1 is actually 6, I should still see the ball? BTW, Autozone has all kinds of stuff I can rent, apparently. (It's all free, you just leave a deposit) If you, or anyone thinks a dwell meter or a certain type of timing light, I'm on it!
Yes You may not be seeing your timing mark because your distributor is off a little Your close enought to start. You just need to dial it in... Most run advanced depending on fuel or engine condition... HF 12 volt light will work. It has an advance dial on the back. Not the best tool but works
I'll check on that tomorrow. Well, as far as the ball goes, you read how I had actually over sprayed the ball and ended up using a tapped hole for a flywheel bolt as what I thought was the ball, right?
His 1st sentence implies that I helped Zig get the cap on a half turn from where it should have been. Not true. I helped him realize that it was a half turn off. Just wanted to clear that up before Ken starts ragging on me.
Yes Might help to clean the overspray off and paint the ball white Again not saying this is your problem Just one more think on the list to check Could be other things mentioned Faulty ignition bits Fuel delivery Valve not adjusted Tackle one thing at a time to eliminate Good luck
Quit worry about this Zig. The crankshaft turns twice for every one turn of the distributor. So the timing mark "ball" will show up when cylinder #1 is due to fire on one revolution of the crankshaft and it will show up again one turn later when #6 is due to fire.
Oh come on, Bill~ Take a bow! You have spent a bunch of time with me talking things through. Absolutely the reason I love this site! And then there's Tubby trying what he can come up with! Tomorrow's D-Day because the 4th is the day after. When I got my truck this far, I really had wild ideas about being parked at the show under the shade of an old oak tree. Hey, there's always next year. The other thing is to give my mom and dad a spin in this before I can't. Time and patience has been the steady force behind this so far, so why change now, right?
Just point and shoot as usual Turn the dial on the back till the ball appears If you end up at 6 on the dial and the ball appears. Then your at 6 degrees advance. My guess is that right now your not advanced enough. But that's just a guess If you advance to far the truck will stumble and miss, sound like a heavy knock.
Bilbo suggested doing this to help determine if this was a fuel starvation problem and I thought it was safer than Evan's suggestion to dribble gasoline into the carb for the same purpose. The logic is that if the engine suddenly ran better it would imply that it wasn't getting enough gas. As Zig says, it made no difference. To me that says that this is an ignition problem, not a fuel problem OR that the engine is getting too much gas after it comes off of idle.
As you can tell, I know enough to really screw something up! Now I know! It was fun timing a tapped hole, however. I look forward to tomorrow. One thing, and I'm not sure it matters but I can hear the very slight missing at idle now. Not sure if this is new, or that my ears are really tuning in on this thing.
Hard to say on the miss It would be nice to know what your idle is set at You can get one of these at sears
My GMC (same motor as Zig's, but runs a lot better) was pulling 16"-17" of vacuum at the factory specified 425 RPM idle and factory specified "on the ball" timing. I upped the idle to 450 RPM (A/C works better during long periods of idling) with no change in vacuum. Then I advanced the ignition timing about half way between the zero and the "A" mark on the thing that I call the "Octane Selector". Vacuum jumped from 16" to 19", out of "late ignition timing" and into "normal" on my vacuum gauge.
I think that would be a good thing to have, considering this truck will be mine for ever and ever. We still have a Sears here, but it is a very small store. Probably have to order it, but I will check if Autozone has something like this for now.
