Timing issue

[palmaceae]

Hello all,
I finally got my fuel leak fixed but installing an original sediment bulb and new fuel lines, but know I am working on my next issue, timing. I followed the instructions on the Les Andrews book. I got the timing real close but I can not get it perfect. I installed a new points, with the correct gap, new distributor cam, new plugs, etc... I can only get it close when the spark advance is all the way up, when you pull it down you lose power, it seems like when the lever is all the way up it runs like it should when the lever is all the way down, and I just can not get that sweet spot. I am trying to figure out what I am doing wrong? Is there a secret to this? There is a little play in the distributor shaft, maybe 1/8" and the most. Any ideas?
Thanks

[Kurt in NJ]

When you say you have play in the dist shaft is it side to side, up and down, or rotational?

If you grab the point plate can you move it side to side ---I just took a dist out of my brothers engine, it had all new parts in it (all repro), the point plate fit so loose that I could move it sideways and change the point gap .030

it is also possible that the wire under the plate is damaged and shorting out

[palmaceae]

The play is rotational, is that normal?

[Kurt in NJ]

Yes, and no, you just have to make allowances for the play --I don't know about how Les says to do it, never read his book, Marco has a method close to how I do it,
http://www.abarnyard.com/workshop/timing.htm

[Marco Tahtaras]

If there is lateral slop in the upper plate as Kurt was asking then the point gap could be changing when you advance the lever. Other than that it sounds like your timing is way too far advanced. This could happen if you really didn't find the depression in the timing gear when you inserted the pin. Another possibility is a Model B front timing cover which would throw you off similarly.

[johnbuckley]

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Sounds like the distributor needs retarding a couple of notches

[Ken B]

I ran into a similar problem. After much frustration, I noticed that the arm coming out of the distributor wasn't all the way to the fully retarded position with the lever on the steering column all the way up. I had to loosen the steering column clamps and rotate the column until the arm was fully retarded. I also had a problem with the reproduction distributor body opening for this arm. It was cut in the wrong position. I put the old original back on and made my adjustments to the column. The timing adjusted just fine after making these corrections.

[roccaas]

If you don't mind taking off the head, turn the engine to #1 TDC (both valves closed).

With a cold chisel, tap a small cleft into the TDC of the crank pulley (not for show cars obviously). Put a small drop of paint on the timing case in line with the cleft. When you time the engine, make sure you look straight down onto the cleft and paint spot. Looking for the marks from the side of the engine engenders parallax which can throw off your TDC timing. A step ladder and looking down from above the radiator is a good way to line up everything.

There was an old article on making a sheet metal arrow that bolts to the head and drops down to point to the TDC cleft. It makes timing my engine on the road very easy.

Make sure you don't time with #1 at TDC on the exhaust stroke or you will have an exhaust manifold full of gas, and all the oil washed off of the cylinder bores!

This is also a good time to check the gasket for blow through between #3 and #4, water leaks, gasket overlap into the cylinders, etc. Tighten and retorque the head in the correct pattern as described elsewhere on this site.

Don't want to remove the head? Take off #1 plug, get someone with slim fingers to feel for the piston TDC (again on combustion) and set the TDC from that position. A little harder to do because the Model A engine is a few degrees past the connecting rod at perfect vertical when the piston is at TDC, but it can be done. Again, use the timing pin as a 2nd opinion on TDC.

Tighten the fan belt and you can rock the engine a few degrees clockwise and counter clockwise to ensure TDC without having to use the hand crank.

I use Marco's excellent check list to set the timing, and the TDC mark is easier to use (and a good double check for the timing pin - measure twice, cut once) when you are setting the timing.

Make sure your distributor is in GREAT shape. Slop leads to widely varying gaps which are annoying and make for less than smooth driving.

I get that sewing machine sound at full spark retard (people love to hear each cylinder firing), and great power at full spark advance.

[1931 flamingo]

All of the above plus Snyder's offers a Cam Tool on pg A-145 of their catalog. Made by Nu-Rex, after finding TDC makes setting timing foo-proof.
p/n A-12210-CX 1928-31 $9.75
Worked for me easier than following Les Andrews and Marco's guidance. JMO
Paul in CT

[palmaceae]

I did find the correct TDC, the dimple was worn down but I know I have it correct and it is not 180 degrees off. I just seem like I get it close then try to move the cam again it goes way off. I will check the lever and where it connects to the distributor again to make sure it is touching both stops.
I also did use that Synders cam tool, works great to get it close.

[Chris in CT]

Hi Palmaceae, If you have 0.125 rotational play (wear) in your distributor shaft, then you have a serious problem. With the point gap at 0.022, you can easily see how it would be impossible either to set or keep the point gap with the radius of the rotational play affecting your points by 0.062. With all due respect to the above good advice, I don't see how you can utilize it until you repair/rebush the distributor shaft. Ramp, advance, dwell, and induction soak are all affected by the point gap and profile of the distributor cam. Rotational free play in the system affects these profoundly. Good Luck!

[palmaceae]

Originally Posted by Chris in CT

Hi Palmaceae, If you have 0.125 rotational play (wear) in your distributor shaft, then you have a serious problem. With the point gap at 0.022, you can easily see how it would be impossible either to set or keep the point gap with the radius of the rotational play affecting your points by 0.062. With all due respect to the above good advice, I don't see how you can utilize it until you repair/rebush the distributor shaft. Ramp, advance, dwell, and induction soak are all affected by the point gap and profile of the distributor cam. Rotational free play in the system affects these profoundly. Good Luck!

Would I replace the entire distributor assembly? How would I go about rebushing the shaft, or would I have to replace the shaft?

[RonC]

Your best bet would be to buy a complete rebuilt distributor with a stock point setup. They are available from the various parts suppliers. I would stick with an origianl rebuilt over a reproduction distributor which are also available.

[Rowdy]

Possibly you are the victom of the misdrilled timing gears mentioned awhile back. Just a thought. Rod

[Marco Tahtaras]

Originally Posted by Chris in CT

Hi Palmaceae, If you have 0.125 rotational play (wear) in your distributor shaft, then you have a serious problem. With the point gap at 0.022, you can easily see how it would be impossible either to set or keep the point gap with the radius of the rotational play affecting your points by 0.062. With all due respect to the above good advice, I don't see how you can utilize it until you repair/rebush the distributor shaft. Ramp, advance, dwell, and induction soak are all affected by the point gap and profile of the distributor cam. Rotational free play in the system affects these profoundly. Good Luck!

It sounds like you are confusing rotational play (backlash from slop in the linkages) with lateral movement from slop in the bushings.

[palmaceae]

Originally Posted by Rowdy

Possibly you are the victom of the misdrilled timing gears mentioned awhile back. Just a thought. Rod

Do you mean the dimple on the timing gear?

[palmaceae]

Originally Posted by Marco Tahtaras

It sounds like you are confusing rotational play (backlash from slop in the linkages) with lateral movement from slop in the bushings.

I may be, there is no lateral movement, just rotational play.

[Rowdy]

No the crank timing gear where it lines up with the mark on the cam gear is on the wrong side of the key way. This was discussed alittle over a month ago. I will see if I can find it. Rod

[Marco Tahtaras]

Originally Posted by RonC

Your best bet would be to buy a complete rebuilt distributor with a stock point setup. They are available from the various parts suppliers. I would stick with an origianl rebuilt over a reproduction distributor which are also available.

Most "professionally rebuilt" distributors I've seen were less than ideal. The most common problems are junk shafts or cams (or both) which make the point gaps vary, and slop in the upper plate from poor fit at the center hole.

[palmaceae]

Originally Posted by Rowdy

No the crank timing gear where it lines up with the mark on the cam gear is on the wrong side of the key way. This was discussed alittle over a month ago. I will see if I can find it. Rod

Oh ok, I will say it used to run good, but when I had a short in the distributor a couple months back this reset the timing since I took the cam off, I have not had it right since then.