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TIMING A P28 FLATHEAD


48ply1stcar

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Just another wrinkle as I attempt to stuff a 56 Plymouth flathead into my 48.

 

I searched the Forums and I have a Service Manual for the years 46 - 54, but apparently or maybe Top Dead Center for my engine does not leave the rotor at 7 o'clock.  I use a rope method, and a piece of paper towel in the spark plug hole to find TDC and both have the rotor at  11 o'clock.

 

Additionally, I have a raised diagram on the cylinder head with a pointer at 11 o'clock.

 

Does anyone else have a 1956 P28 engine or did I just get lucky.

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the cast pointer is a shift ID mark from the foundry.  Some one probably messed with your engine and did not properly index the oil pump.  As the distributor drive position depends on the position of the slot in the oil pump to drive it, where ever it is, if you are sure you are on TDC compression for #1. use that and go from there on your firing order for the plug wires.  Lots of oil pumps got repaired, or swaped with no regard for proper position.  My 56 engine like about 5 degrees BTDC as an initial setting your experience may vary.

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Don

 

Just another thing I learned on the (World Wide Webs). 

 

After I found a spot where the paper towel blew out of the spark plug hole I knew I was close.  So I stuff thin anchor rope into the cylinder.  I turn the crank clockwise until it stopped and marked the pully with chalk.  Then I turned the crank counter-clockwise until it stopped and marked it again.  I split the difference to give me an approximate TDC.

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What is stopping the piston?  as the spark plug hole splits the intake/exhuat valve location, unless you shove in a whole bunch of rope, you aren't accessing the piston.  That is why Chrysler engineers cleverly included a pipe plug in the head over #6, and designed the engine so that when #6 is at TDC so #1.

 

As long as you know #1 is on compression, sticking a stiff wire into the hole blocked by the plug the wire will ride up and down on the top of the piston allowing you to precisely locate TDC.  Make sure the wire is long enough to accommodate the stroke, and remember to reinstall the plug when you are finished.

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As Greg said the hole (as pictured below) above the #6 piston is best for finding TDC on cylinders #1 and #6. The rope trick is used on overhead valve engines to hold the valves in the closed position while replacing valve springs and possibly valve seals without removing the engine cylinder head.

 

If, when your engine is at TDC on cylinders #1 and #6 and your rotor is pointing to anywhere but 7:00 or 1:00, your oil pump is not indexed per factory recommendations. However your engine can still be timed perfectly if you understand how to do so. The only reason the factory recommended the 7-1 position was to make things easier for the mechanic out in the field who had to remove and replace the distributor.

 

To time your engine make sure the piston on 1-6 is at TDC. Then simply note the rotor position and install the plug wires in the cap accordingly following the firing order 153624. 

 

h1.jpg

 

h2.jpg

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I always have used a sealer be it teflon sealer or a permatex type on all water or oil pipe fittings, but in this case being over the combustion chamber and heat?. Not sure- will they become a glue with the high heat?. Maybe just a lube to get the fitting a tight fit.?

 

Other thoughts/experiences?.

 

DJ

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The line adapters from the tranny to the radiator on my truck are pipe thread on one end and always weeped  a bit after a new radiator was installed.  They didn't stop until I used a bit of Teflon tape on the threads.  If you don't want to use or are worried about the tape, a bit of pipe dope will work, or more old school, rub the fitting with a bar of bath soap.

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GUESS WHAT

 

When I use used the plug over the 6th cylinder - The rotor lined up perfectly at the 7 o'clock position - go figure.

 

Just goes to show if one can over think something I'll be in line for overthinking.

 

Thanks to everyone for you input and keeping me going forward.

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Pipe threads are supposed to be self-sealing, since there is a taper built in, but I always use some sort of sealer.   

Technically this isn't always true.  There are actually two different thread forms specified for pipe threads; the less common form is self-sealing, but the usual form is not, and requires some sort of sealer.  I've pretty much given up on Teflon tape sealers, and now use pipe dope almost exclusively.

 

Marty

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Technically this isn't always true.  There are actually two different thread forms specified for pipe threads; the less common form is self-sealing, but the usual form is not, and requires some sort of sealer.  I've pretty much given up on Teflon tape sealers, and now use pipe dope almost exclusively.

 

Marty

 

I too have pretty much given up on Teflon tape sealers. Pipe dope/compound does a much better for me.

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