Distributor orientation
Discussion
audi321 said:
Hi could anyone tell me if it matters which way round this distributor goes in? I’m assuming there is a right way and a (180 degrees) wrong way?
Or doesn’t it matter as long as I point the rotor arm at lead 1 at TDC when it’s in?
My head can’t work it out lol.
The rotor arm needs to be pointing to lead 1 when cylinder 1 is at TDC on the firing stroke (rather than exhaust stroke). You need to check that all valves are closed at TDC when you put the distributor in. Or doesn’t it matter as long as I point the rotor arm at lead 1 at TDC when it’s in?
My head can’t work it out lol.
jeremyc said:
audi321 said:
Hi could anyone tell me if it matters which way round this distributor goes in? I’m assuming there is a right way and a (180 degrees) wrong way?
Or doesn’t it matter as long as I point the rotor arm at lead 1 at TDC when it’s in?
My head can’t work it out lol.
The rotor arm needs to be pointing to lead 1 when cylinder 1 is at TDC on the firing stroke (rather than exhaust stroke). You need to check that all valves are closed at TDC when you put the distributor in. Or doesn’t it matter as long as I point the rotor arm at lead 1 at TDC when it’s in?
My head can’t work it out lol.
...or, if you can't see the valves/rocker/cam lobes, simply check for compression in cylinder No1 (finger over sparkplug hole) as you bring No1 piston up to TDC.
audi321 said:
Cheers guys. I’m aware of the TDC situation and importance, what I’m struggling to get my head around is if there is a right and wrong way to install this. It’s basically symmetrical so it can go either way in and assuming I have the correct TDC can it go in either way?
I would guess so, yes.But first: what does the Haynes manual say*?
*or indeed any other workshop manual for the engine.
audi321 said:
Cheers guys. I’m aware of the TDC situation and importance, what I’m struggling to get my head around is if there is a right and wrong way to install this. It’s basically symmetrical so it can go either way in and assuming I have the correct TDC can it go in either way?
If I've understood correctly ? It's not symmetrical. Known to me as a D drive, the "blade" is off centre.
Eg - http://www.mgb-stuff.org.uk/drivedog.htm
Edited by Maxdecel on Wednesday 12th July 18:11
Hi, it will sit on in the block either way, no matter. The important thing is to then rotate the body to get the rotor arm just touching the contact point for the lead running to cylinder 1 at approx the right BTDC point, say start at 8 degrees.
Is your dizzy isn't restricted in how you can rotate it, it really doesn't matter
If it is a B it is 1-3-4-2 firing order I believe.
Is your dizzy isn't restricted in how you can rotate it, it really doesn't matter
If it is a B it is 1-3-4-2 firing order I believe.
Thebaggers said:
Hi, it will sit on in the block either way, no matter. The important thing is to then rotate the body to get the rotor arm just touching the contact point for the lead running to cylinder 1 at approx the right BTDC point, say start at 8 degrees.
Is your dizzy isn't restricted in how you can rotate it, it really doesn't matter
If it is a B it is 1-3-4-2 firing order I believe.
I take that back if it isn't symmetrical Is your dizzy isn't restricted in how you can rotate it, it really doesn't matter
If it is a B it is 1-3-4-2 firing order I believe.
Thebaggers said:
I take that back if it isn't symmetrical
Distant recollection for dist. drive : set on TDC #1 Install with slot pointing to #1 plug and one "D" facing down. But it's a few decades since I was that far in to a BMC engine 
Not seen that drive method on any other makes ?
Maxdecel said:
Thebaggers said:
I take that back if it isn't symmetrical
Distant recollection for dist. drive : set on TDC #1 Install with slot pointing to #1 plug and one "D" facing down. But it's a few decades since I was that far in to a BMC engine Not seen that drive method on any other makes ?
jeremyc said:
Maxdecel said:
Thebaggers said:
I take that back if it isn't symmetrical
Distant recollection for dist. drive : set on TDC #1 Install with slot pointing to #1 plug and one "D" facing down. But it's a few decades since I was that far in to a BMC engine Not seen that drive method on any other makes ?
We may find out, and I'll be completely wrong
The slot and drive are offset from the centre, it will only go in one way, the casing/cap/rotor arm need to be oriented so that the rotor arm aligns with the lead that goes to the cylinder that is at TDC with all valves closed, finer adjustment can be made once the engine is running.
Dave
Dave
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