Got TDC!!

[Bingster]

Finally after all your help it clocked and I got TDC on #1, it lined up with DC on the pulley, and got the rotor to One O'clock.

 

Question: How long does TDC last?

[Dave72dt]

TDc is only 1 degree.  It's effects are only a few degrees.  Does your statement mean your Cyl 1 on compression and rotor pointing to 1 o'clock or Cyl 6 is on compression and rotor pointing to 1 o'clock?  First scenario puts your timing 180 degrees out, second means you got it right.

[Bingster]

Really?  I thought I heard somewhere that #1 had to be on compression.  I take compression to mean when a small piece of paper will blow outward of a cylinder spark plug hole.  I put a piece of wire in the pipe hole above #6, turned the fan until the wire stopped rising and kept turning the fan again till the wire stopped rising again.   At that point the piece of paper over #1 did move. I guess I have to do it the other way around.

 

I thought that folks were telling me to put my finger on #1 and turn the fan until I felt a push on my finger.

[46BulldogDodge]

The normal...factory setup will have the rotor pointing at 7 o'clock, causing the points to open and fire the spark close to TDC on the compression stroke igniting the fuel/air mixture from the intake.  Piston #6 travels up and down exactly in tandem with piston #1 except it is on the exhaust stroke pushing the burned gases out. Since the tang on the bottom of the distributor (looks like a flat blade screwdriver) connects to the oil pump, it can be correct or it can be 180 degrees off.  If it's off 180 degrees then #1 cylinder will be at compression when the rotor is at 1 o'clock.  This will work but the plug wires must be rotated 180 degrees to match....that would be #1 at 1 o'clock, #5 at 3 o'clock, #2 at 5 o'clock, #4 at 7 o'clock, #3 at 9 o'clock, and #6 at 11 o'clock.

 

If the oil pump is off by a tooth or two when installed, the #1 plug wire location to match TDC compression can be closer to 6 o'clock or 8 o'clock.

 

When you wrote "I put a piece of wire in the pipe hole above #6, turned the fan until the wire stopped rising and kept turning the fan again till the wire stopped rising again.   At that point the piece of paper over #1 did move.", you successfully located TDC on #1 compression.  This is where the engine needs a spark to ignite the fuel/air mixture and power the piston back down.

 

Dick Hultman

SW PA

'46 Dodge WC & '57 FFPW  

[maok]

2 hours ago, 46BulldogDodge said:

The normal...factory setup will have the rotor pointing at 7 o'clock, causing the points to open and fire the spark close to TDC on the compression stroke igniting the fuel/air mixture from the intake.  Piston #6 travels up and down exactly in tandem with piston #1 except it is on the exhaust stroke pushing the burned gases out. Since the tang on the bottom of the distributor (looks like a flat blade screwdriver) connects to the oil pump, it can be correct or it can be 180 degrees off.  If it's off 180 degrees then #1 cylinder will be at compression when the rotor is at 1 o'clock.  This will work but the plug wires must be rotated 180 degrees to match....that would be #1 at 1 o'clock, #5 at 3 o'clock, #2 at 5 o'clock, #4 at 7 o'clock, #3 at 9 o'clock, and #6 at 11 o'clock.

 

If the oil pump is off by a tooth or two when installed, the #1 plug wire location to match TDC compression can be closer to 6 o'clock or 8 o'clock.

 

When you wrote "I put a piece of wire in the pipe hole above #6, turned the fan until the wire stopped rising and kept turning the fan again till the wire stopped rising again.   At that point the piece of paper over #1 did move.", you successfully located TDC on #1 compression.  This is where the engine needs a spark to ignite the fuel/air mixture and power the piston back down.

 

Dick Hultman

SW PA

'46 Dodge WC & '57 FFPW  

 

If you follow this, you won't have any issues timing your engine.

[Los_Control]

6 hours ago, Bingster said:

Really?  I thought I heard somewhere that #1 had to be on compression.  I take compression to mean when a small piece of paper will blow outward of a cylinder spark plug hole.  I put a piece of wire in the pipe hole above #6, turned the fan until the wire stopped rising and kept turning the fan again till the wire stopped rising again.   At that point the piece of paper over #1 did move. I guess I have to do it the other way around.

 

I thought that folks were telling me to put my finger on #1 and turn the fan until I felt a push on my finger.

Sounds like you did everything just fine.

The question now is, "where is the #1 spark plug wire located on the cap?"

 

If the #1 wire is at 1, 0'clock on the distributor cap along with the rotor  .....  Then someone installed the distributor 180 degrees out and they just adjusted the wires to correct it.

 

If the #1 wire is at the 7, 0'clock position on the cap, then someone installed the distributor 180 out and it would not run    ..... they got frustrated and gave up on it and sold the car?

 

This is why we are always saying, you need to find TDC compression stroke to check it ..... you never know what the guy before you did.

The car will run fine this way, as long as the spark plug wires are moved to correct location.

My #1 is at 6, 0'clock because previous owner installed the oil pump 1 tooth off ..... you just never know til you check.

 

As others said, if you follow the factory instructions TDC the rotor will be pointing at  7, 0'clock position.

The distributor is slotted like a flat blade screw driver. It can only be installed 2 ways ..... If you lift it up and rotate the rotor 180 so it is pointing at 7, 0'clock it will now be as the factory manual says.

 

Just to start it up, it will be fine as long as plug wires are moved to correct it.

[Bingster]

I did end up following your plug wire order on my distributor, Bulldog.  I haven't been able to turn the engine over because the starter is spinning but not engaging.  It worked a couple of weeks ago.  Can it be unstuck somehow?  Probably the solenoid went South.

[squirebill]

I'm new to this post.  Bingster, what engine are you working on?  If it is a Mopar flathead 6, the firing order is 1,5,3,6,2,4, going in a clockwise direction looking at the distributer rotor.  The firing order given by Bulldog above is 1, 5, 2, 4, 3, 6.  This might work for some engine but it is not the correct firing order for a Mopar flat head 6.  Regards.      

[46BulldogDodge]

My mistake....brain fart.  Thanks Squirebill for correcting!

[Bingster]

I have a 1947 flathead 6. I've seen various firing orders to use under certain conditions.  Not certain which to use.

[soth122003]

Firing order for all DeSoto's 1935-1953 flat head sixes. 1,5,3,6,2,4. from the Motors Manual. Just make sure that No. ! spark plug wire is at the rotor position with TDC. Usually at the 7 o'clock position. If the rotor position is at any clock angle at TDC the no. 1 plug wire must be at that spot with the following plug wires in a clockwise to follow no.5, 3, 6, 2, 4. Then if the gas is good and the air is good....BOOM it should fire.

 

Joe Lee

[Los_Control]

Is actually easy to remember if you are a pervert like me 

153624 ... 15 is to young, 36 is too old, 24 is just right  

That saying has been around for decades, makes it easy to remember the firing order on the flathead 6's.

[Bingster]

For a 70 year old guy, makes it easy to remember when I was 25.

[Matt Wilson]

19 hours ago, Bingster said:

For a 70 year old guy, makes it easy to remember when I was 25.

For us old guys, 36 still seems pretty good, eh?

Edited October 21, 2023 by Matt Wilson

[DonaldSmith]

When I turned 80, i didn't feel that old; But when I turned 81, I felt that old. 

 

Everything hurts, but thankfully, not all at once. The other day, briefly, nothing hurt at all  I felt like I was 65 again. 

[Hickory]

That is the firing order on 95+% of all straight 6 engines including diesels

[Bingster]

But isn't that for distributors where the rotor is factory set at 7?

[Hickory]

21 minutes ago, Bingster said:

But isn't that for distributors where the rotor is factory set at 7?

The firing order is always the same, just because the rotor is pointed somewhere else doesn't change the position or order of your pistons. You just start the firing order wherever your rotor is as long as you are tdc on one that's where your rotor points. Technically it can be anywhere. The factory spot is 7.

[Fernando Mendes]

"Since the tang on the bottom of the distributor (looks like a flat blade screwdriver) connects to the oil pump, it can be correct or it can be 180 degrees off.  If it's off 180 degrees then #1 cylinder will be at compression when the rotor is at 1 o'clock.  This will work but the plug wires must be rotated 180 degrees to match."(46BulldogDodge)

I think this is my case.Since I am in this forum I did never hear someone explaining this.My B3-B is running very well but its #1 plug wire in dizzy cap is between 2 and 3 o'clock.Can I change #1 plug wire to between 7 and 9 o'clock keeping the firing order 1-5-3-6-2-4??

[Sam Buchanan]

The #1 wire MUST be where the rotor is pointing when #1 cylinder is TDC on the compression stroke. Proceed from there with the correct firing order on the cap. Changing plug wire position on your very well running truck will transition it to non-running....

 

Your oil pump is installed 180 degrees from standard as it is on my very well running P15. Don't mess with it. 

Edited October 22, 2023 by Sam Buchanan

[Los_Control]

@Fernando Mendes If you really are concerned and you want to change it.

If you remove the distributor hold down bolt, then lift the distributor up about 2", rotate the rotor/shaft 180 degrees and then set the distributor back down.

Then it will be what you want.

 

As @Sam Buchanan says, it will not run any better, it will just be for your peace of mind.

Just remember if you move the distributor 180, you also must move the plug wires with it.

[Fernando Mendes]

If you really are concerned and you want to change it.

If you remove the distributor hold down bolt, then lift the distributor up about 2", rotate the rotor/shaft 180 degrees and then set the distributor back down.

Then it will be what you want.(Los_Control)

I ask if rotate the rotor/shaft 180 degrees to clockwise ou counterclockwise?

[Fernando Mendes]

After I was thinking and saw that it doesn't matter one way or the other.

[Fernando Mendes]

[Fernando Mendes]

Hi folks.Since october'2006 in this forum.Throughout all these years I learned and started to admire this family DPCD engines.My IND 251 Chrysler timing chain cover does not have the pointer and when I have to put the #1 cylinder in TDC I put a little tool over the #6 cylinder hole.When this tool begins to rise means that the intake valve begins to open and #6 cylinder is in the end of the exhaust.In this same moment #1 cylinder is on TDC firing stroke.For me the paper or cork process is difficult to believe perhaps due to the pressure of my engine.