Oil pump distributor timing

[Bryce Mcclintock]

So the p26 motor arived back from reconditioners but he seemed a bit unsure he had the pump drive in the right place for the distributor timing.  So with the engine sitting on a pellet i decided to check it all it was out so followed the book got it so distributor rotor is facing 7 o'clock great so hooked up battery to earth on engine and a inline light to distributor to set static timing at 2 degrees BTDC .this being set this set rotar arm off to the clockwise side of cylinder no 1 pin is that normal ? So i rolled engine over by hand and watched the rotar and light to see how it sat at the next pin but it went well past 5 and half way to 3 before indicating buld went out signaling fire . ? Im so confused what have i done wrong ? Im pretty sure no 1 was at TDC firing and the pump was put in as per manual .? Any Hints 

[DJK]

What is the point gap/dwell setting?

[Bryce Mcclintock]

No i havnt checked that yet i assyme you mean points gap or rather the time the points are open .surely this woulnt put it out of sink though if it out may affect how it runs tho obviously 

[Bryce Mcclintock]

Ok so checked points gap its fine . I went back threw and started from scratch finding TDC outing oil pump drive in correctly getting 7 o'clock position on rotor did stactic timing and same problem bu position of rotor it looks like its past each plug wire terminal before it fires is this correct ? I would have thought it needs to fire pointing at terminal? 

[squirebill]

So on the bottom of the distributor housing is the plate you use to adjust the timing.  This plate has a tab that is visible with a "hotdog" slot and permits you to loosen the mounting bolt, adjust the timing, and then retighten the mounting bolt.  This plate is attached to the bottom of the distributor housing with another bolt and a bigger "hotdog" slot.  Seems to me this bolt needs to be loosened and the distributor housing rotated so the plug tower is more in line with the rotor when the points "fire".  Not sure if this adjustment can be done with the distributor on the engine.  Seems like it could be done easier by removing the  distributor. Regards 

[Bryce Mcclintock]

Ive played with that slot it gets me no further ahead at all i can line everything up then go to time it with the small hotdog it puts it back in this weird position . Is it possible the reconditioners have not lined up the timing gears properly? 

[Plymouthy Adams]

more likely....oil pump is indexed one tooth off and you may need to address this....procedure is in later published books.

[Bryce Mcclintock]

Ive indexed so many times now and so other variants as well this was the closest i can get it i did follow the book and rotor is in 7 o'clock position its when i do the static timing it comes to the clockwise side of pin ?

[Plymouthy Adams]

when static timing you rotate the distributor....not the engine...

[Bryce Mcclintock]

NYes i know  i put the engine at 2 degrees BTDC then rotated distributor with a indicator bulb hooked up to set it moving distributor clock wise till bulb lights then moving it counter clockwise and stopped the moment it went out 

[squirebill]

My 1949 parts manual has a 10 tooth gear for the oil pump drive so one tooth off would be more like 36 degrees off (360 degrees divided by 10).  If I remember correctly, when the oil pump is installed properly, the slot in the pump shaft that drives the distributor is pretty much horizontal.

[Bryce Mcclintock]

Thanks yes thats where its at . Can anyone else have a look to see where the rotor is pointing when the points begin to open . I k ow im close but feel it reslly is to far off to the clockwise side of plug wire terminal. 

[squirebill]

Considering  the  plug towers on the cap are 60 degrees apart and one tooth off on the oil pump is 36 degrees off....could be why rotor seems to be between two towers when the points "fire".  I agree with  Plymouthy Adams, check your oil pump installation again.

[Sniper]

Compared to the timing marks on the balancer/pulley, if the oil pump is one tooth off it is 18 degrees, at the balancer/pulley, since the cam moves at half the crank rotation.

Edited December 29, 2021 by Sniper

[Bryce Mcclintock]

Ok off with pump and ill try again thanks for your everyones input 

[DonaldSmith]

As I remember from my motor rebuild a dozen years ago, the pump gears are helical, so that if you line up the slot of the shaft. and insert the pump, the shaft rotates a bit.  So you have to anticipate that rotation.  I saw the instructions somewhere in the shop manual.  But now I can't find it.     

[squirebill]

Correct...in my manual the instructions are in the "Engine Oiling System" section of the "Engine" chapter.   So yesterday had some time and popped the distributor cap off the B1B and took some measurements.  The notched pins coming to the inside of the cap are .250" in diameter.  The flat blade on the rotor is .375" wide.  The radius of the circle the rotor would make is 1.125".   All this calculates to about 32 degrees from when the leading edge of the rotor is aligned with the leading edge of the pin to when the trailing edge of the rotor passes the trailing edge of the pin.   Seems to me as long as the points "fire" somewhere in the 32 degree arc all is good.  Point being the rotor does not have to be centered under the plug towers of the cap to get proper ignition.  So maybe where it is is good enough.

[Sniper]

Remeber that the 32 degrees you measured also has to take into account the timing changes cause by both the mechanical and vacuum advance.  You can not just set initial timing so that if fires somewhere along that 32 degrees.  You need to put it where the spark can fire at any point from initial timing to full mechanical and vacuum advance, so your window narrows a lot.

[Dave72dt]

Maybe someone who has the oil pump properly oriented and is comfortable pulling the distributor out can put it on #1 compression, pull it and post a pic of the pump slot and of the rotor and points positions for the OP.  Is it the correct cap for that model distributor?

[Bryce Mcclintock]

I assume its the correct cap it was a running engine before taken apart i do have another cap ill see if there is a difference 

[keithb7]

I get into this topic here:

 

 

Maybe I am wrong but I thought that no matter where you decide to index your pump and distributor, as long as the spark plug wires are placed accordingly, #1 position at TDC #1, could be anywhere it the circle of the distributor cap. Sure you might be out one tooth. I have done this before. You can remove the distributor rotating lock bolt and twist it father than normal. Then when the engine fires and runs, you know you are are out. Pull the distributor, set it back a tooth and give 'er another go.

 

[Dave72dt]

Thanks, Keith.  I think that will help.

[Bryce Mcclintock]

Ok so ive been on holiday but was talking to a friend and he suggested perhaps there is a roll pin or rivet that may have broken and allowed the tang to have spun a little before jaming again putting it of line with rotor is that a possibility with this distributor?  Ive never had one completely broken down or seen an exploded view of one . What angle should tang be in relationship to rotor ? I know mine are definately not lined up ? 

[Sniper]

Here's a thread about making an electronic ignition distributor out of one of the flathead distributors.  It shows very clearly that the tang is an integral part of the shaft, no roll pin or similar to go bad.

 

https://www.jalopyjournal.com/forum/threads/mopar-flathead-6-distributor-upgrade-48-desoto.653565/