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2 hours ago, Radarsonwheels said:

 

Now I am confused too.

 

Why does the motor care which wire on the distributor is for the #1 sparkplug as long as the wires are put in the proper firing order? The pump is constantly spun whenever the crank spins, as does the rotor in the distributor cap and the cam for the points breaker right? Am I missing something or did I always just get lucky?

 

I never met a motor that wouldn’t fire and time with the rotor aimed at just before the tower for the #1 plug on it’s compression tdc.

 

I can say that on a slant 6 there is only so much adjustment slotted into the distributor hold-down before you need to go underneath to loosen the slotted plate and spin it.

 

On a smallblock LA the distributor is driven with a slot so it can only stab in right or 180 out on a running motor. You can pull the oil pump drive and re-index the slot though just like pulling the whole gear driven distributor in a slant 6. The amount of adjustment on them is 360° but a vacuum can on a stocker can start to get in the way in some positions. 

 

On some motors the oil passages to different areas like the top end on some degrees of rotation. Maybe it’s something like that?

 

I have worked on my old 230 but never built one up fresh and not for a few years other than plugs oil and tune-ups. I certainly am not trying to be a know it all or take exception to your doing it the way it was intended by the manufacturer- just throwing ideas out there trying to understand.

 

radar

simple, you have to take the answers in context with the question posted in post #7     

 

If you ever removed the oil pump in a flathead you would have timed the gear to the cam in regard to the distributor or indexed the tower as the oil pump mates to the cam and drives the distributor...on a total rebuild, you will have to align all from scratch on assembly and THAT IS ONLY IF YOU WISH YOUR WIRING ON THE TOWER TO BE THAT OF THE BOOK...you can do it anyway you want, AND as the mopar LA 8's (even big blocks) you mentioned have an intermediate gear that IS TIMED on install to the cam for the same purpose this gear drives both the distributor and the pump...you simply just index the oil pump on any of the six drive flats....slant six as you mention is yet a different setup as both the distributor and oil pump have their own individual gears running off the cam at just less than 90 degree to each other.  Of the four mentioned engine groups in this post, only the LA has an internal oil pump....the rest are externally serviced.

Edited by Plymouthy Adams
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The only trouble I could really see come from this, if the oil pump and distributor weren't indexed correctly, is that when you adjust the timing on the distributor while rotating, you could end up having to turn the distributor so then that the vacuum advance goes into the engine block, which would suck.  

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As I understand it the only reasons the factory selected the 7:00 position was to make life easier for the mechanics in the field to have common ground to start with when doing tuneups. And as mentioned above to prevent the vacuum advance from making contact with the engine block.

 

Military distributors took it a step further. The "tang" at the bottom of the distributor shaft that is flat on both sides of civilian distributors was modified adding a half moon on one side so the distributor could only be installed one way not two ways. They did this so when you are in a gun fight with bullets wizzing over your head and the engine craps out you can make hasty repairs in the dark and get out of Dodge.

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On 2/13/2019 at 7:21 PM, MackTheFinger said:

In his first post Larry mentioned small block Chevy motors. In those the oil pump is driven by the distributor, different from the Mopar L-head. I'm sure that's what he was thinking about vis-a-vis oil pump timing.

 

Bingo!  It finally dawns on me that regardless of what I read, saw, or heard my brain was not putting it together.  Thanks for the help................and patience

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8 hours ago, thisoldtruck said:

The only trouble I could really see come from this, if the oil pump and distributor weren't indexed correctly, is that when you adjust the timing on the distributor while rotating, you could end up having to turn the distributor so then that the vacuum advance goes into the engine block, which would suck.  

 

actually the body of the distributor can still be indexed in location to the side of the block as normal as IT IS the shaft that is turned by the oil pump drive and the notch that locks the rotor that will dictate the index of the distributor cap....basically the point is that if you wish to follow along in the book for tuning, it is best to index the oil pump for proper rotor location on the distributor.

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  • 10 months later...

Been reading through this and found some great information, but still have a few questions.  I got the pan pulled off my block, learned that the dipstick tube threads in so that's one problem solved.  Now my question is with the oil pick up, and pick up tube.  The tube appears to be threaded into the block?  With regards to the oil pick up and getting the screen cleaned out etc.  The cover that is on the bottom is what's removed for internal access?  Just bend tabs back carefully? 

Thanks. 

Eric

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