The Stovebolt Site Forums The Shop Area Engine Shop Clarification needed!!

When stabbing in the distributor on a 216 cu. in. Chevrolet engine are the intake and exhaust valves on #1 cylinder both closed, or just the intake? The shop manual stated that the intake valve should close and to rotate the engine until the timing mark on the flywheel lines up with the U/C marking. Should the distributor be stabbed in at the U/C mark on the fly wheel or at the BB? Right now my intake valve is closed and the exhaust valve is partially open and the pointer on the bell housing is directly pointing at the BB.

Tim

You are on the overlap stroke. You can stab it in that position by using #6 cyl. In other words stab it so the rotor is pointing to #6 in the cap.

Wrenchbender Ret.,

Thanks for your response! So I'm 180 degrees off TDC? Wouldn't be better if I set the engine at TDC? Do I use the BB or the U/C marking on the flywheel?

Tim

The crankshaft rotates twice to cycle through all 6 cylinders.

Therefore the timing mark on the flywheel show up twice - only on one of those two times are both valves closed for the #1 cylinder .

You'd be 360 degrees off.

Easy way to set the dist.
With the dist out.
1) pull plugs
2) spin engine while holding finger over #1 sparkplug hole.
3) Just as soon as you start to feel compression pushing against your finger stop spinning engine.
4) Slowly turn engine until the BB lines up with the pointer in the timing hole. (You want to turn the engine in the same direction it was spinning).(if you let it spin too far you can slowly manually spin the engine in the other direction if needed).
5) Your engine should now be at the #1 plug firing position.
6) Note the position of the slot in the oil pump drive. You may have to turn it with a long shank straight slot screw driver.
7) Drop the dist in with the vacuum advance pointing towards the front of the engine and the rotor button pointing to approx 5 o'clock position. If it drops all the way in, good.
If it doesn't you may need to turn the oil pump slot to align with the dist tang.
8) If the #1 plug on the dist cap doesn't line up at the 5 o'clock position with the dist fully seated-the rotor pointed to the 5 o'clock position and the vacuum advance pointing straight towards the front of the engine, move the plug wires around until it does.
The dist turns clockwise so with #1 wire plugged into the cap at the 5 o0'clock position, going clockwise, plug your wires in, in this order, 1-5-3-6-2-4

That'll be good enough to start and run and should be real close to the final timing setting.

You're already lined up right. With #6 on overlap, #1 is ready to fire. Drop the dizzy in, and use the plug wire the rotor is pointing toward as #1. Wire the rest of the firing order clockwise, 5-3-6-2-4. Now turn the distributor housing clockwise until the points close, and turn it back until they just barely open. Lock the housing down, install the cap and rotor, and fire it up.
Jerry

Jerry,

Now I'm confused! Don't know if #6 is on overlap. I think #1 is on overlap. Intake valve is closed on #1 and exhaust valve on #1 is open. Timing mark "BB" on flywheel is directly under the pointer. Stab the distributor in with the cylinder #1 valves in this position or should both the intake and exhaust valves be closed?

Tim

OOPS! I misread your post. I turn the engine until the #6 valves are on overlap (exhaust closing, intake opening) and time the distributor to fire #1. One and six come to the top of the stroke at the same time, (companion cylinders) with the camshaft determining which one is ready to fire. Ditto for 2 and 5 and 3 and 4. Sorry about the mistake!

If you don't want to make another turn of the crankshaft, just use #6 as your starting point with the engine in its present position. You can set the initial timing on either cylinder close enough to run.
Jerry

I am up against thesame deal. Did you get it to fire? Did you use the BB or UC? I have fuel to carb, weak spark to number 1 cylinder and followed the procedure described here. I have a 6 volt alternator and am wondering how fast it needs to spln to charge.

I am still re checking all the variables but no success yet Shouldn't be this hard

I would guess the pulley size would be chosen to charge at normal idle (6-700 rpm), at least with only minimal accessories. Yes, that's much faster than cranking speed.

MikeE,

I did not try to fire the engine yet. I got the distributor set on TDC using a vacuum gauge adapted to a compression gauge hose in #1 cylinder spark plug hole. Moved the crankshaft until I got compression on # 1 cylinder and continued to move the crankshaft clockwise, about 1/3 turn until the pointer on the bell housing lined up with the "BB" on the flywheel. Primed the oil pump. Stabbed the distributor in with the cap spring clips parallel to the push rod cover, and lined the rotor button up so that #1 spark plug wire on the rotor cap is in the 6 o'clock position. Made sure the distributor seated firmly so the oil pump drive was engaged. Tightened the distributor clamp at the slotted screw in from of the distributor. Attached all the plug wires in the proper firing order. 1,5,3,6,2,4. I've been told this should get it started so the proper timing can be set with a timing light. Will try to fire it in the next few days. My '49 has been converted to a 12V system with a 1 wire alternator.

Hope this helps.

Tim

You can get within a degree or two of the correct timing by using the points closed/points open procedure I described in a previous post. The spark happens just as the points break, so eyeballing the place where they just break contact will get you close enough to start.
Jerry

Jerry,

I'm using a Flame Thrower 3 ohm internal resistor coil and ignition module. This ignition module has no magnetic sleeve and no adjustable air gap. Do I need to set the distributor cam so the high side points towards the ignition module or back it off so flat side of the distributor cam faces the ignition module before starting?

Thanks,

Tim

I had to walk away for a while and charge the battery as well. My next move is to go over the TDC confirmation again and static it time it again to number 1. probably Monday.

MikeE,

Sometimes we ALL have to walk away and go back to it!! I've found when it's time to walk away and I don't, tools get thrown, and curse words that I thought didn't exit begin to spew from my mouth. Lost tools and the embarrassment of someone hearing these foul derivatives of the English language is not worth the grief or high blood pressure. We'll all get this and if I run across a REAL trick or secret to getting these old beasts started, I will let you in on it!

Tim

I haven't quite got to that point on this yet. This more than likely my own headspace and timing being off and a simple mistake.

I try to stay as far as possible away from any electronic ignition except the OEM General Motors units. Most of them use horrendously expensive proprietary components, and their reliability sucks like a Dyson vacuum cleaner. I have no idea how to time that one, and no incentive whatsoever to learn how to do it!

Another advantage to the GM system is that it's pretty idiot-proof. Unless the distributor is turning at least 200 RPM, there's absolutely no current draw by the module, so an ignition switch left on by accident CANNOT run the battery down or burn out a module.
Jerry

Jerry,

Understand! Not exactly the answer I was looking for, but I'll figure it out. I have used Pertronix units in the past with VERY GOOD results, but most were 4 cylinder and V8 applications. Anyone else who has installed this unit and has tips or suggestions would be most welcome.

Tim