Timing of Engine

Cape Codder

Cape Codder

Well-known member
I have followed the instructions that Marco has posted on line. I have a question as to the results. Below is what he has posted:

The rotor position shown above is the proper position with the timing pin in the gear depression and piston #1 at TDC. The dashed line shows the position of the rotor when #1 fires with the spark lever fully advanced (down).

So after setting it as he says in the first sentence, when I put the spark lever in the advanced (down) position it moves very little. Nothing like what he promotes with the illustration showing the rotor just coming to the #1 pin on diet. body?

My question is why???? And how can it be fixed???
 
Hi Cape
Moving the advance lever down only rotates the upper plate with the points... It does not move the rotor...
 
It means that when the lever is advanced, #1 won't actually fire until the rotor is in that position, based on when the timing of when the points close. In the retarded position, #1 will fire sooner (later?).
 
Hello All, Got a newbe question for you all. I have a 1928 and supposedly the engine was rebuilt... but the owner I got the engine from could never get it to start. so I bought it. And I went through every possible bit of info to get it into timing. I won't waste your time reading and my time typing but after trying the same thing over and over I tried something different I timed the engine as though number 4 piston was number one and in three seconds it fired up and ran like a new engine. Now I want to know why any thoughts?
 
how are you numbering the cylinders? front to back or back to front

and we can assume the electrical/ignition system is stock?
 
I find it rather humorous to read of the great efforts expended (and debates engaged in)to set initial timing on an A. Someone fusses, fudges and repeats several times, then proclaims he has his timing set to a gnat's eyelash. He fires it up and pulls the advance lever "down about 3/4 of the way" like someone told him told to do, and drives off blissfully unaware that he just undid all his painstaking work! Once you move that lever even one click, the timing is no longer where you initially set it. Do you know exactly how much each 'click' advances the timing? No? Do you know exactly how much timing your specific engine likes the best? No? Every engine is just a bit different.
All this OCD behavior over initial timing is pointless!
 
All this OCD behavior over initial timing is pointless! end quote


Pointless !? Now we don't even have points !? [ smiley face]
 
Hey TBird, thanks for your questions, I was following Les Andrews among others to set the timing. And with that thought in mind was using the pin to find TDC on the cam gear, then using the NU-REX wrench to set the rotor onto the front most point of the distributor. This done because all the books say that fires the spark plug for the front most cylinder. But nothing at all that way engine would just turn over and over. I also watched Jack Bahm's you tube videos many times and set the timing just like that but still nothing. So for something different I took the NU-REX wrench and turned the rotor to fire on cylinder number 4 as you know the opposit side of the distributor. And it started... And as far as I know all is stock except for the NU-REX points and condensor that I installed. I am just wondering why it is this way. As I stated the previous owner said someone else had rebuilt the engine. could they have put something in backwards inside ?
 
Since the crank turns twice for each turn of the cam gear, and the timing mark is the dimple in the cam gear, I don't see how the timing can be off. I would pull #1 spark plug and feel for compression as you hand crank the engine. When you feel compression on #1 then start pushing in on the timing pin, and it should drop into the dimple as soon as the compression stops. This will be TDC firing for #1, and the rotor should be pointing toward the right headlamp, exactly as the picture shows.
 

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A Model A is very easy to set the timing. I do it like Tom has posted. It works every time. Once it is done unless you loosen the rotor shaft screw it is done for ever. I think people are making it a lot harder than it really is.
 
For BoyToy, I helped a person with a Model A once and could not get him correct, until I tried setting the pin on the indentation of the timing gear and using a thin wire through the spark plug hole, found that the indentation was not set for TDC of #1. I never stuck around to get the cover off to see what was going on, but obviously you could have the entire timing of the cam and timing gear set incorrectly for #1.
 
Since the two dowel pins are only slightly off from being straight across from each other, I suppose someone could have forced a fiber gear onto the camshaft 180* out of sync, and this would then fire #4 instead of #1 when the timing pin drops into the dimple. I've never heard of this happening, but some people have done some amazing things to these engines.

Someone forced an aluminum crank pulley onto the crankshaft with the pulley groove not lined up and made a new groove and damaged the key on the engine I'm fixing up right now.
 
Guys thank you so much for your imput!!! The crazy thing is that I had checked TDC with the pin in the cam gear and by looking down inside the cylinder with both valves closed to make sure I was doing it right. It just would not start so my thoughts went to someone installed the cam gear in the wrong place. so I took the timing cover off. And it was perfect right where all the book say it supposed to be. My engine was set up just like Tom's pictures show. But nothing. So I changed only the rotor to fire on number 4 cylinder instead of number 1 and it instantly started and runs great. Drove it 2 miles today for fun and stress release. I know this seems crazy but I am at a loss as to explain it. I spoke to Bob at NU-REX and he is sending me a timing system to put on the engine and try to find out what is going on, he said he has never heard of this happening before. Any chance my car was made on the first monday after Christmas 1928 ???
 
Me thinks you were not using the nu-rex tool correctly. Supposed to rotate the dist cam about 2 revolutions and set the edge of the tool against the rear most pin on the dist cap (#4), then tighten the cam. I'm wondering if this is what you were doing??
Paul in CT
 
Hey Paul, thanks for asking about the NU-REX wrench, but to what little defense I could ever have mechanically I was using it just the way Bob Gay from NU-REX said it was to be used. I even went so far to ask Bob what could be the difference. He said that years ago a few of his wrenches were bent wrong and when used produced the wrong setting so I texted him pictures of the wrench and he said that the wrench was correct and we walked through it again how I had done the set up. Bob said in all his years he has never had anything like this happen my and Bob thoughts are that maybe some how the dimple on the cam gear was put 180 degrees out which produced my situation ??? Your thoughts are welcome and wanted. Thanks for your help. Larry Stout, PA
 
I know this does sound a little nutty but try another distributer cap ,you never know a little Asian lady might be having a little fun on another boring day at the offshore repro distributer cap factory !!! I have had a new repro cap which did try to fire the wrong cylinder but not all four .

John in rain showers cold Easterly wind all the way from the Steppes I guess I will blame Vladimir Suffolk County England .
 
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