Timing

[Herr Otto]

Now that I have spark and the slant 6 is running , I want to time it. I have adjusted the valves set the dwell but I am unable to get it timed to the exact spec. I can come close but not exact. If I remove the distributor and rotate it clockwise a tooth I still can not get it exact. If I remove the distributor and rotate counter clockwise same problem. I can get it within 10-15 degrees either BTDC or ATDC but not to 2.5 -5 BTDC as required. The timing mark is not wandering.

Thank you,

Otto

[grey beard]

Otto,

A few things you might check on this problem:

Is your crank pulley damper rubber mountred? Might it have moved on the pulley?

Find top dead center with a piece of wire through the number one spark plug hole - turn it over by hand with the fan blades till the piston is at the very top of its travel, and see if your pulley TDC mark is true. Mabye someone changed some parts somewhere before you owned it.

Most distributors have a clamp you can loosen to get more travel on the distributor turning adjustment. If you've pulled your distributor out, check underneath to see if there is another clamp or bolt you can loosen on the bracket. Fladhead sixes all have this on the bottom of the distributor body. I have never seen a distributor that could not be adjusted past one plug wire hole in either direction. Check it out.

Let us know what you find.

Good Luck

[greg g]

try using a vacuum gauge then check it with the timing light. Also is your idle speed correct, it its too fast, the advances will start to work.

To use a vacuum gauge, attach it to a vacuum port on the intake manifold. Then with the engine running at proper idle speed rotate the distributor to attain the highest steady vacuum reading. Then check the timing withthe light ad see where you are.

With today's gas a bit more advance over spec is not really a bad thing as long as you get good starts and no pinging under load (accelerating or climbing a hill) If your timing is wandering it might be that the distributor bushings are worn.

[Don Coatney]

Find top dead center with a piece of wire through the number one spark plug hole -

Dave;

How can you do this when the spark plug hole is above the intake valve?

There is a hole in the head above the number 6 cylinder used for finding TDC as pictured.

[Frank Elder]

Dave;

How can you do this when the spark plug hole is above the intake valve?

There is a hole in the head above the number 6 cylinder used for finding TDC as pictured.

Pretty sure it's a slant six Don.

[Herr Otto]

One of my problems is it has been 20 years or so since I have worked on a standard ignition system, with that said I forgot to disconnect the Vacuum advance when timing the engine. I will do that sometime today and let you know the outcome. I appreciate all the great suggestions.

Otto

[Tom Skinner]

Herr Otto,

Its OK to run it 15 degrees BTDC thats where I run mine.

You don't have to disconnect the Vacumn advance to set the Timing

on these old Flat Heads. Hook Up the Vacumn Gauge and Set it that way.

Tom

[grey beard]

Hey Y'all,

The man sez in his initial thread that he's runnin' a /six, NOT a flattie.

Fifteen crank degrees of initial advance, on top of what our falthead distributors put out in the centrifugal and vaccuum advance departments would give nearly 45 degrees advance at 2800 rpm. I don't think any engine would tolerate that much advance.

This would mean that the spark event would occur with the piston rod at a horizontal plane, and the piston only half way up on the compression stroke. Wanna' check that initial timing again?

Greg, I have found that when I have too much initial advance on my own engine, it really pings, but not till about 2800 rpm. That happens at about 55-60 mph, NOT on a hard pull away from a hole shot. You need enough engine rpm to get full centrifugal advance, along with the initial and centrifugal advance, to get preignition, IMHO.

If it pings at 30, on a pull, it'll REALLY preignite at 60.

Check it out.

Good Luck

Check it out.

[MBF]

I caught the /6 reference myself. If the timing mark is moving with the vacuum port plugged, and the idle backed down-you may need to check for wear in the timing chain, gears, and the nylon drive gear on the distributor shaft! You can't set timing on an engine with a worn chain/gears and expect it to hold. I'd remove the distributor cap, and rock the engine back and forth with the fan blades to see how far you can move the crankshaft before the rotor starts to move. Excessive play will require digging deeper. Mike

[Herr Otto]

I disconnected the Vacuum advance and plugged it. I also I found the bolt under the distributor in addittion to the one at the block and loosened it a bit. I was able to set the timimng now. Thank you all for your help.

Otto

[greg g]

Dave I'm only talking 3 to 6 degrees BTDC. Mine is currently at 5 degrees. I believe you can attest to its efficacy.

[grey beard]

Greg,

You're cool. Sure does run nice, however you have it set up. Wish mine was that smooth . . .