Can't seem to get enough advance on the distributor

[Wes Flippen]

Recently finished an in car engine re-build on my '50 Coronet L-230. New pistons and rings. Ground and lapped the valve seats. New valves and guides. Compression in eache cylinder went from about 70 psi each to 125 each, so I'll count that as a win. Did not mess with the distributor at all. Turned the key, and engine rolled over, but no start. Accelerator pump working fine and getting fuel to the carb so tried adjusting timing. At full mechanical advance on the front and rear adjustments, I could get the car to start. Starting was hard and car ran very rough. Backed off the timing and no start, but backfired through carb. ( yeah, I know it's not technically a backfire when it blows through the carb.). Tried moving plug wires back one place on the cap and adjusting the distributor, but no dice. Any suggestions?

Thanks,

Wes

[Wes Flippen]

Also; yep, the rotor is pointed at 7:00 o'clock when #1 cylinder is at TDC.

[Doug&Deb]

Have you tried both adjustments on the distributor? Did you replace the oil pump during the rebuild? If so is it indexed properly? 

[1949 Wraith]

Have you adjusted the distributor lockdown plate? Usually a clamp or bolt underneath that will allow you to adjust the range for the distributor lockdown.

[Sniper]

Did the cam come out?  If so did you verify the reinstallation?

[Wes Flippen]

Have adjusted both adjustments. The one on the side of the dist. and the one on the back. Never pulled the Cam, oil pump, or distributor. Had issues trying to adjust timing when I first got this car a couple of years ago. Had to roll the distributer all the way counterclockwise with the rear adjuster. Mainly just wondering if any one else has run into this and what did you do to fix it.

[kencombs]

Since it has been a problem before, I'd suspect someone in the past removed the oil pump and didn't index it correctly. 

[Doug&Deb]

Remove the plugs and manually turn the engine to tdc and see where the rotor is pointed. We never know what previous owners have done to these cars.

[keithb7]

Worn internal distributor parts maybe? Unable to get the spark timed up to where you want?  What if you removed all or any bolts or plates that lock down the distributor and prevent further twisting movement? Could you then turn the distributor shaft far enough,  that you could get it to fire at the precise time you need?

[maddmaxx1949]

Here's how I just did my M37 after the timing got all buggered up. Same thing, I couldn't seem to get it to fire.

 

1.) Locate TDC using static timing procedure.

2.) Gap points at 0.020 or whatever it calls for for your vehicle.

3.) I started with the distributor major adjustment all the way to one side, tightened then reinstalled distributor.

4.) With ignition on and cap removed. Loosen minor adjustment. rotate distributor by hand until you see/hear a spark at the points.

 

If you do not get a spark, try your major adjustment again, maybe somewhere in the middle then repeat step 4. Also turn your ignition off before you remove the dist or you might get zapped.

 

If you don't get spark at all, it may be worn distributor parts. make sure your points are contacting each other and getting separation. The moment they break/separate is when you should be at TDC or whatever you want your timing set to be.

Edited July 20, 2021 by maddmaxx1949

[greg g]

Many of the distributors have a bolt on the bottom thar will allow some additional degrees of rotation. 

[Wes Flippen]

I'll give maddmax's method a go. I'll let you guys know.

Thanks,

Wes.

[Sniper]

One thing to note, each cylinder, during the four stroke cycle, will have two TDC events.  Only one of them is useful for setting the timing and it's the one that occurs at the top of the compression stroke.

 

So pull at least the number one plug and feel for air coming out the plug hole, that's the compression stroke and you want to use the TDC that occurs then.  If you pull all the plugs you can turn the engine over by hand, I can usually pull on theh fan belt to turn the engine.

 

The OP might already know this, but others may not.

[maddmaxx1949]

Thanks Sniper I did indeed forget to mention that. I feel like I had already posted it but it was on another thread. They all start running together....

[Loren]

One of the tools I always have in my box or travel bag is a test light.

If you have a non-starting car, a test light will tell you if you have power at the coil (ground at battery to negative at coil - assuming you have positive ground).

You can tell if the points are working (ground at battery to positive side of coil at cranking - the test light will flash each time the points open).

Lastly you can check the initial timing (ground at battery to positive side of coil, turn the engine by hand to the timing mark then turn the distributor until the light just goes off) When the light is on the points are open, when the points close the light goes off. When you are timing the engine you want to be at that critical point when the points are opening - that's when the spark is created.

 

The test light will not tell you when you are 180 degrees off.

That's another procedure which involves knowing where the cam shaft is in it's rotation. On an overhead valve engine you can remove the valve cover and see which valves are opening. Number 1 and number 6 are at TDC at the same time but 180 degrees apart in cam timing. 2 & 5, 3 & 4 are paired the same way. The valves at TDC don't look like they are open or closed - they are rocking because they are going from closing exhaust to opening intake - the cylinder on compression has both valves closed for the power stroke and that's the one that is firing.

On a flathead the simple way is to do the above tests with your test light then pull the distributor and rotate the rotor until it points to the paired cylinder such as 1 to 6. Now your'e 180 degrees from where you started. If it runs, good...if not something else is wrong.

Having the firing order in front of you and checking the rotation of the rotor when cranking will tell you if you have the plug wires right.

There's nothing magical or secret here, it's all logic.

[Wes Flippen]

Loren,

As an electrician, I know all about test lights, though I prefer to use a multi-meter. When I first got this car, I upgraded (or downgraded, in some peoples opinion) to a pertronix module, as I was having issues with the points. Ran fine with the module for several months. I'm getting fire, just can't roll the distributer far enough advanced to get to 6 degrees BTC, which is the sweet spot. May have worn out bearings causing play in the distributor. I dunno. Mainly just wondering if anyone on here had run into this issue, and what they had to do to remedy it. I do appreciate the advice however.

[Loren]

 

There are two different fastenings to these distributors.

That flat plate under the distributor head can be moved two ways and that should be plenty to get you in the ball park.

VWs had the same system. The distributor can be rotated in the plate and the plate can be rotated on the engine block.