Timing

I have a 1971 55HP Chrysler. As you read my engine no longer starts after cleaning up under Flywheel. I remove the spark control link and the spark control bearing. I just screwed it all back together. does this control the timing? By just screwing this back on did I mess the timing up? Can this being the reason why it won't start?

Re: Timing

sorry noah 4009, just read your other post ,will see if I can help

Re: Timing

YES! Screwing it in or out will adjust timing. You should have marked the locknuts or otherwise noted the original position. However, from practical experience I can tell you that you could screw it all the way out or in and the timing would change only a couple or so degrees either way.--it will not affect starting capability AS LONG AS ALL OTHER VARIABLES ARE WITHIN FACTORY SPECS.

You have already said you are getting spark BUT:

1. Is the spark strong enough to jump about 1/2 inch?
2. Is the correct wire on the correct coil and sparkplug? 180 degrees out of timing and the engine will not start.
3. Disconnect the fuel line from the carb and drain the bowl. Pour about a teaspoonfull of fuel mix through the carb into the reeds. Now crank the engine. It should crank until it clears itself then fire and run for about 1-2 seconds. If it does this, you have a fuel related problem--not spark. If you crank for more than say 15-30 seconds and nothing happens, then it is probably a spark related problem.
4. Did you re-check the flywheel key AND extension to the cam? A broken key or extension will let the cam out of alignment and the spark will be at the wrong time. IF you did not torque the flywheel nut to about 95 foot pounds and the engine kicked the first time you tried to fire it, it may have broken the key.
5. No matter what ignition you have, the points should be set at .020 open when the rubbing block is on the cam high point.
6. If you have battery and coils ignition, you need to be certain that the condensers are good and you need to check power to the plus side of the coils.
7. You did reconnect the ground wire from the points plate to the block, didn't you? Failure to use this wire will result in weak spark or no spark at all.

Re: Timing

Frank Acampora said:

YES! Screwing it in or out will adjust timing. You should have marked the locknuts or otherwise noted the original position. However, from practical experience I can tell you that you could screw it all the way out or in and the timing would change only a couple or so degrees either way.--it will not affect starting capability AS LONG AS ALL OTHER VARIABLES ARE WITHIN FACTORY SPECS.

You have already said you are getting spark BUT:

1. Is the spark strong enough to jump about 1/2 inch?
2. Is the correct wire on the correct coil and sparkplug? 180 degrees out of timing and the engine will not start.
3. Disconnect the fuel line from the carb and drain the bowl. Pour about a teaspoonfull of fuel mix through the carb into the reeds. Now crank the engine. It should crank until it clears itself then fire and run for about 1-2 seconds. If it does this, you have a fuel related problem--not spark. If you crank for more than say 15-30 seconds and nothing happens, then it is probably a spark related problem.
7. You did reconnect the ground wire from the points plate to the block, didn't you? Failure to use this wire will result in weak spark or no spark at all.

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Do I remove carb or just bowl? If bowl, do I put back on after draining? You say pour gas in reeds. What is the reeds? I also just removed the flywheel and checked the breaker plate.(coil and points attached on top of) Is this also known as the point plate? If so I did not see any wire coming from it as a ground. Only wires are to coils and points. Did I forget about this? I do not remember this wire and my motor is electric alternator. No magneto. My parts manual does not show a ground wire. Also what is the extension cam?

Re: Timing

There is a black wire that attaches to one of the screws that pass through the plate. It is long enough so that it can attach to one of the screws holding the top clamp for the tower and still let the plate move. Coil plate, breaker plate, point plate--yeah, we are talking about the same thing.

As far as the carb, just drain it so you know it is not flooding the engine and ensure that the gas you pour in will eventually clear. Replace the bowl, then pour gas behind the throttle butterfly into the manifold and reeds.

If you have not yet disassembled it, behind the carb is the manifold. behind the manifold is a plate about 1/4 inch thick that holds the reed vee blocks and reeds. Each vee block services one cylinder. Each vee block has 4 reed petals on each side sealing it for a total of eight petals per cylinder.

Reeds are one way valves made of thin spring steel that allow the piston to induct fuel air mix on the upstroke (compression) and seal on the downstroke (power) to blow the mix through the transfer ports into the cylinder and combustion chamber. They are called reeds because they are very much like the reeds of a woodwind musical instrument or a saxophone. Indeed, sometimes you can hear them "honking" as the engine turns over.

This is also part of the engine noise you will or may hear while it is running--if you know what to listen for. Since the reeds are vibrating at, say, 5000 divided by 60 equals 83 cycles per second at full throttle, this is a musical note well above the lower threshold of 20 cycles per second that the human ear can hear. That plus overtones from secondary vibrations.

Re: Timing

Frank, I look at my parts manual and it only shows a ground wire on magna power that attaches to plate. But for the electric alt, which is mine, it shows no ground lead in my parts manual.

Re: Timing

It may not show it but it is way better to have it. The points are grounded through the plate and the plate is or can be electrically separated from the block by the grease it rides on. The wire is just redundant grounding to ensure a good ground is available.

Re: Timing

Frank Acampora said:

It may not show it but it is way better to have it. The points are grounded through the plate and the plate is or can be electrically separated from the block by the grease it rides on. The wire is just redundant grounding to ensure a good ground is available.

Click to expand...

Frank, when the tower was sticking, I removed the plate. After cleaning plate I put grease around it and under it. There was no grease around or under it before I did this. I'm thinking the grease is stopping it from grounding. But would I still get a spark from plugs if grease is causing the problem? How do I ground? Your other post says ground should be long enough to let plate move freely and connect to top clamp that holds tower, correct? Do I connect ground wire to any screw on plate? What gauge wire should I use? Thanks

Re: Timing

The original wire on the magneto ignition engines was 16 or 18 gauge. It can be connected to any screw on the plate but mine was connected with a nut to one of the screws that held the plate to the lower retainer (the aluminum ring that holds the plate down.)

A poor ground will cause a weak spark and if the plate is completely insulated by grease it could cause no spark at all. BECAUSE: The ignition coil consists of a primary winding of heavy copper wire wound around an iron core, The secondary winding is many times more turns of a fine copper wire. The coil is a step-up transformer which changes approximately 12 volts to approximately 10,000 volts.

When the ignition key is on, 12 volts is applied to the positive terminal of both coils. When the points close, the coil's negative terminals are grounded through them and current flows. This builds up the magnetic field in the coil primary. The length of time the points are closed is called DWELL and is regulated by the opening gap and cam design. Dwell controls the amount of magnetic field that is generated inside the coil. Thus: if the points are not properly grounded, a smaller amount of current will flow and a weaker magnetic field will be generated inside the coils.

When the points open again, current stops flowing and the magnetic field rapidly collapses, cutting through the secondary windings. This induces an extermely high voltage pulse, proportional to number of windings and magnetic field strength, which will jump the gap of the spark plug.

The condensers act to slow the stopping of the current when the points open and prevent arcing and pitting of the points. HOWEVER: since the condenser is also grounded, a defective or shorted condenser will keep the coil negative terminal grounded and no voltage pulse will be generated.

Re: Timing

Thanks Frank, I did as you say and still won't start. Just backfired and carb pouring gas again. I give up. Thank You, Craigslist here I come