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#1
Old 03-21-2002, 09:04 PM
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Join Date: Mar 1999
Location: Berkeley, CA
Posts: 14,089
Set timing with no timing light?

I have an old '62 Chev. pickup with a 292 ci 6 cyl. engine. Runs great, but.
Isn't there a way to set the timing "close enuff" without a light? Dwell I can do with a feeler guage, and idle speed and mix by ear.
I just use the old thing to go to the dump, etc, and want to get rid of a rather strong hesitation between idle and 'go'.
I think shade tree mechanics are the coolest people on earth.
Peace,
mangeorge
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#2
Old 03-21-2002, 09:16 PM
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Location: Houston, TX, USA
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I haven't done that in years, pal, but it seems that if you know the spec and can get it zeroed at TDC, you could probably fake it by ear. Probably much easier to just borrow a timing light for the few minutes it'll take you to do it.

::reminisces about points and coils and the like::
#3
Old 03-21-2002, 09:27 PM
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Join Date: Dec 2000
Location: Austin, TX
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Do they not have parts stores with tool rental (or even free lending with a deposit) out there in Cali? You could even be dishonest and buy one, use it and return it for a refund.

You can get it close by ear, but if you want to get rid of that hesitation, you ought to tune the thing the right way, with a timing light.
#4
Old 03-21-2002, 09:32 PM
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Yes, you can do it by ear but of course, it may not be exactly precise.

As fewer and fewer cars have distributors, timing lights are getting harder and harder to find.
#5
Old 03-21-2002, 09:52 PM
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Join Date: Apr 1999
Location: Houston, TX, USA
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Help me out, here, folks. I have not set the timing on a car since sometime in the '70s, so I'm digging at faded memories. If he can get the car zeroed at TDC, can he rotate the distributor X (spec) degrees and get it right?

Also, mangeorge, if you need it, I believe I still have a timing light. I have no further use for it, and I'll dig it out and send it to you if you'd like. I just need to make the effort of looking this weekend to make sure I still have it. Let me know - I don't mind at all.
#6
Old 03-21-2002, 10:00 PM
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Join Date: Mar 2001
Location: Out of my mind.
Posts: 1,146
Loosen distributor bolt so you can turn distributor.Mark location.

Start truck. Turn distributor clockwise until engine dies,
mark location. Turn back to original mark.

Start truck. Turn distributor anticlockwise until engine dies. Mark location.

Put distributor equally between high and low marks.

This isn't exactly correct, of course, but it works on the side of the road in the dark with a flashlight held between your teeth- I've done it many a time.

Actually, you could just try turning it a tiny bit clockwise, and then a tiny bit counterclockwise, and see where it runs better and doesn't hesitate.

I see cheap timing lights at garage sales all the time. I paid $1 for mine.

b.
#7
Old 03-21-2002, 10:35 PM
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Join Date: Jan 2001
Location: Walnut Creek, California
Posts: 1,367
My bro and I used to do this on our 64 Chevy. But he like to use the timing light. First thing you need to do is find the correct setting for the distributor angle, and mark it. Since the vehicle presumably now has really high miles on it, you will need to adjust it by hand a few degrees to advance the spark. Then run the engine at various RPMs to get it right by sound. You may have to take it out on the road a few times to put the engine under load and do so readjusting. But don't overdue the use on the engine. Old engines with self adjusted distributor settings shouldn't be run hard or with heavy loads on them. I recommend a new rotor, points and condensor, distributor cap, spark plugs and wires too. You'll need to gap the plugs, and set the points to correctly. Oh, what memories of greasiness I have. Glad I went into law.
#8
Old 03-21-2002, 11:12 PM
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Sure you can adjust the timing without a light. Set the dwell first, since that will affect the timing somewhat.

What your are looking for essentially, is to advance the timing to the point (as so well described in the above posts) just before engine knock. Safely test your adjustments by 'punching it' at low speeds and passing speeds on the highway. Correct timing will manifest itself by quick starts, smooth idle, fuel economy and good driveability and power at all speeds without knocking or stumbling.

Still, a dwell-tach and timing light is the way to go. The methods described will get the old gal running well enough, though.
#9
Old 03-22-2002, 07:34 AM
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Posts: 614
The hesitation you speak of can also be caused by and in my experience is more likely to be caused by a worn acelerator pump. If timing doesn't fix it you might want to get a jiffy kit for the carb.
#10
Old 03-22-2002, 08:21 AM
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Join Date: Mar 2002
Location: KCMO
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There is a procedure for setting the ignition timing to the spec without a timing light. It requires a test light or a voltmeter. Carefully done, it's rather accurate, easily within one or two degrees.

First, set the point gap, or better yet, the dwell angle. If a dwell meter is available, that's definitely preferable to a gap measurement. Experience has shown me that in many cases the specified point gap doesn't always result in the specified dwell. Dwell angle is what you really want, point gap is an approximate way to achieve it.

You need to know which direction the distributor rotor rotates. A manual will tell you, or you can observe it by cranking the engine with the distributor cap off or by watching while doing the next step.

Bring the crankshaft to the timing spec. In other words, if the spec is 5 degrees before top dead center, you want the pointer at the 5 degree mark. It must be brought there in the direction of normal engine rotation (clockwise on the overwhelming majority of cars, but observe it to be certain). Rotating backwards to line the mark up brings in any timing chain slack and skews the synchronization between the crankshaft and the distributor (which is driven off the camshaft). If you pass the mark, you can go back a ways beyond it to "reset," but be sure the final motion is two inches or more of crank pulley circumference in the direction of normal rotation.

Loosen the distributor hold-down enough to be able to turn the disributor. Connect the test light or voltmeter to the coil negative terminal (which should connect directly to the points in the distributor), with its other end connected to ground. Turn the ignition switch on.

If the points are open, the test light will light up (or the voltmeter will read battery voltage). If the points are closed, the light will be off (voltmeter reads zero). DO NOT ALLOW THE POINTS TO REMAIN CLOSED WITH THE IGNITION ON ANY LONGER THAN NECESSARY. This burns points up in short order. Side note: generally you want to avoid having the ignition on with the engine not running. If the points happen to be closed, they will suffer. Use the accessory position or let the engine run.

If the light is on, turn the distributor in the direction of its rotor rotation until the light goes off. (If the light is off, presumably it's already where you want it.) Now turn the distributor in the OPPOSITE direction of its rotor rotation until the light comes on. Go back and forth a time or two to get the feel of it. You want the distributor to be at the exact point where the light just comes on when rotating it opposite from rotor rotation. Tighten the distributor hold-down. Done.
#11
Old 03-22-2002, 09:06 AM
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Quote:
Originally posted by Gary T
There is a procedure for setting the ignition timing to the spec without a timing light. It requires a test light or a voltmeter...
Bingo.

If you don't have a ohmmeter, set the engine on the compression stroke, then remove the distributor cap and put some cellophane from a pack of cigarettes between the points. Pull gently on the cellophane as you rotate the engine towards top dead center. The cellophane will move when the points open, and this is where your timing is currently set.

You might also try turning the engine until you're at the timing mark, retarding the distributor and then turning the distributor until the cellophane pulls out, but you would probably want to check it again by turning the engine afterwards to make sure the timing is right.
#12
Old 03-22-2002, 09:34 AM
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I used the test light method, as suggested above, on my VW for a long time. I didn't even need the light, as I could hear a spark across the points as they opened. So set the timing mark by turning the engine (somehow), turn on the ignition, rotate the distributer to hear the spark.
#13
Old 03-22-2002, 11:48 AM
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Join Date: Mar 1999
Location: Pacific Grove, Calif
Posts: 17,493
Timing set at TDC is only for some cars, not all. Some are not set at TDC, but near it, check your owner manual, you'd be surprised. I find that numerous mechanics think that all cars should be set at TDC, but this is not the case. WHere to set it can also depend on the type of gas & altitude, I suppose.
#14
Old 03-22-2002, 10:21 PM
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Join Date: Mar 1999
Location: Berkeley, CA
Posts: 14,089
Thanks, folks.
I think I'll try the method with the meter first. That's the one I remember, with your help. If that doesn't do it I'll find a light. They're getting rare.
And thanks for the offer, Ringo. But I'll probably have it done, one way or the other, by this weekend. Awful nice of you to offer, but the junk is piling up.
Peace,
mangeorge
#15
Old 03-23-2002, 10:03 AM
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Join Date: Jul 1999
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$ 20. from ebay "buy it now" shipping included

http://cgi.ebay.com/ebaymotors/ws/eb...156614&r=0&t=0

and it looks like there are many even nicer ones you could get for $5 to $6 + shipping.
#16
Old 03-23-2002, 02:01 PM
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Join Date: Apr 1999
Posts: 517
old chevy timing

I don't remember that particular year chevy but here are a couple of points:

If it has the old chevy vacuum advance system the "lump" on accelerration could be a defective advance diaphragm.

Also there is a 'floating pigtail' inside the distributor which allows the distributor plate to rotate in response to vacuum levels.

If the insulation on the pigtail has broken down due to motion it might be instantaneously/momentarily shorting out your primary wire.

Another way to set your timing is with a vacuum guage.

Connect the vacuum guage to the intake manifold and rotate the distributor to find the highest vacuum reading.

Assuming that the engine isn't approaching melt down the vacuum at sea level should be 20"-----------with a drop in vacuum of one inch for every 1000 feet of elevation.

Lock it up at the highest vacuum readfing and yopu're all set for the track!

Good luck
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