Cam Timing Gear

purplewg

Junior Member
So I jus replaced my first cam gear and thought I had the marks c. It fired up and ran but but was shooting flames out the exhaust. lol This one has a newer style distributor cap so I couldn't see the rotor. I had set the timing pin and set my distributor timing using a light. I knew the rotor was pointing in the general area of #1 but couldn't see it with the cap on. I finally found an old distributor cap and this is what I see setting on TDC with the rotor on. I am assuming I am a tooth off on the cam timing gear. What do you think? Thanks
 

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Looking at the rotor you can not determine if the cam is off. The rotor can be adjusted to any position you wish. I suggest you recheck your ignition timing before going any farther.
 
Looking at the rotor you can not determine if the cam is off. The rotor can be adjusted to any position you wish. I suggest you recheck your ignition timing before going any farther.

Yeah, that is with the ignition timing in the distributor set per where the points close for #1. Looks way too far off to me. I used a test light to watch when the points close because my old can see a light easier than the actual points. lol
 
Ok, I pulled the front and timing cover back off. Looks like I got it right the first time. This is a pic of the cam gear meshing with the crank gear.
 

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The picture shows the cam gear in the correct position. I would suspect ignition timing is too retarded. Remove rotor arm and slacken the screw under it, then rotate cam anticlockwise [in your case possibly from "11 o'clock" to "10 o'clock" ] to advance the ignition, retighten screw and replace rotor arm. I find that doing it a smidgin then roadtesting is easy and certainly fun. Optimal ignition timing will vary with engine speed, temperature, load, fuel, etc etc
 
looks like a lot of backlash and the crankshaft gear teeth look rusty—- such damage to crankshaft gear will eat fiber timing gear quickly
 
Yeah, that is with the ignition timing in the distributor set per where the points close for #1. Looks way too far off to me. I used a test light to watch when the points close because my old can see a light easier than the actual points. lol

You want to set your timing when the points OPEN. The coil fires when the points open and the magnetic field collapses.
 
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You want to set your timing when the points OPEN. The coil fires when the points open and the magnetic field collapses.
If you are using an indicator light with one lead clipped to the points arm, one lead clipped to ground, and key on, when the light goes ON is when the points open.

JayJay
 
If you are using an indicator light with one lead clipped to the points arm, one lead clipped to ground, and key on, when the light goes ON is when the points open.

JayJay

That's correct but read what the OP wrote in post #3...
 
And that is where his problem lies. Setting point cam/rotor at points closing instead of opening. With rotor blade directed towards #1 terminal.
 
Rotate the crank shaft until the pin drops into the detent. Fully retard the ignition lever. Move the distributor shaft clockwise. The points should be closed. Now move the distributor shaft counter clockwise and the points should slightly open. You can see this with your eyes and don't need a light or ohm meter. If you have very poor eyes use a magnifying glass. There is enough slop in the distributor drive that the slight rotation counter clockwise will just open the points. You can rotate the distributor shaft back and forth to check for the slight opening. If you have a lot of slop in your distributor drive, just rotate the distributor shaft a small amount and the points should open. If this is not happening, adjust the cam and check again.
 
With your point gap set at .020", your rotor should be close to this position when properly timed, lever fully retarded.


516861
 

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Thanks for all the input folks. Maybe I should clarify how I set the timing. I set it with a test light so this is how I did it.
1. Set the timing pin in the detent on the timing gear while monitoring #1 piston for TDC.
2. Turn cam in counter clockwise direction until the breaker points are fully open (light comes on) this is where the rotor is pointing generally toward #1 on dist cap.
3. Turn the cam back in a clockwise direction until the points just close (light goes off).
4. Tighten the cam locking screw making sure I didn't move the cam using the cam tool.
5. Pull down on spark advance lever. The test lamp should come on (points open) at about notch 2.

Sorry for any confusion.
 
With your point gap set at .020", your rotor should be close to this position when properly timed, lever fully retarded.

Thanks, I put an old original dist cap on and used the Nu-Rex tool to set the timing, started it up and it ran like crap. Then I went back and put the timing pin in to set at TDC again and rechecked and rotor was setting about 3/4 inch off from where I had set it. I did this exercise about three or four times and each time it was never where I had set it after starting. I have to assume there is just too much slop every where. I have raised the surrender flag on this one.

My friend has 3 of these in various stages of disrepair. This motor is toast. While working on it I discovered several things that made me just give up. 1 is I found leaks around the number one cylinder where someone had used JB weld to try and stop water leaks on the #1 water jacket. 2 when I am trying to set the timing pin in the notch I hear what sounds like a piston/ring noise clank while rotating the crank by hand. 3 I had put fresh anti freeze in the motor(new radiator) when I put a new timing gear on. When I drained it to go back to double check I had aligned the gears correctly it had oil in the anti freeze. 4 what little time it actually ran it was dumping oil out of the rear main.

I talked to my friend and told him my recommendation was to either by a decent running engine or see if he can find a rebuilt engine and replace this one.

It is a cute little homemade hotrod. I will get a pic and post it here later. lol

I appreciate all the inputs here.
 
Purple, If things are changing after you set the timing then there is something wrong internally. You are right to consider a different engine or an overhaul. I am a curious fellow and I would take it apart just to see what is wrong inside.
 
Distributor cam lock screw bottoming out before it's tight??? Does your screw have a washer and lock washer???
 
Purple, If things are changing after you set the timing then there is something wrong internally. You are right to consider a different engine or an overhaul. I am a curious fellow and I would take it apart just to see what is wrong inside.

I agree 100%. Knowing the state of this engine, I would doubt the gear built into the cam that drives the dist and oil pump may be shot.

I may get a chance to looking inside this engine as the owner and I talked last night and I told him to either find another engine or let put a late model Ford 4 cylinder in it. lol Picture to follow.
 
Distributor cam lock screw bottoming out before it's tight??? Does your screw have a washer and lock washer???

No the dist cam seems to stay where I put it. After tightening the cam screw I tried to turn the cam with a Nu-Rex tool and after the slop was gone it didn't want to move at all.
 
Ok, here is Model A in question. I think it is a cute little parade cart. lol The owner has another Model A I have worked on. The engine in it is decent. I suggested swapping engines between the two. The other one has a hodge podge of frame hacks done to it. Either that or drop a late model Ford 4 cylinder in it.
 

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