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M10 Rotor Arm Position

Posted: Tue Jul 21, 2020 11:17 pm
by martauto
Hi guy`s hope you are all safe and well ??? (as can be :mad: )

Can anyone please tell me the position of the arm when on No1 cylinder ??
And, also which direction does the arm go please ?? (clockwise or anti-clockwise)
I seem to have got this side of it wrong so I need to start again.

Many thanks and keep keeping safe and well :cool: :cool: :cool: :cool:

Mart.

Pics would be lovely :clap: :clap:

Re: M10 Rotor Arm Position

Posted: Wed Jul 22, 2020 11:07 pm
by martauto
Any takers guy`s I`m stuck here 8O 8O

Mart.

Re: M10 Rotor Arm Position

Posted: Thu Jul 23, 2020 7:24 am
by flybynite
Mart, have you not got a Haynes or Bentley?

Unfortunately I have never owned a 4-cyl BMW so most of my manuals are 6-cyl but the Bentley covers the 1.8i so from the book of words

"The distributor shaft will want to rotate approximately 30° as the bevelled drive gears disengage. Notice the position of the rotor after removal, in order to position it approximately the same way prior to reinstallation."
The firing order is 1 -3-4-2, that is, looking at the top of the distributor cap,
To determine the location of cylinder no. 1 on the distributor cap, remove the cap and look for a small mark on the rim of the distributor housing.
The tower on the cap which aligns with this notch is for cylinder no. 1 , followed by wire no. 3, wire no. 4, and wire no. 2.
Cylinder no. 1 is at the front of the engine (closest to the radiator)

"To determine the direction i n which the rotor rotates, place the transmission in a high gear and move the car forward, just until the rotor begins to move. The direction in which the rotor moves is the firing order direction."


If you can see it there is usually a direction arrow on the side of the dizzy too

HTH

Re: M10 Rotor Arm Position

Posted: Thu Jul 23, 2020 11:16 am
by Brianmoooore
This is easily worked out from first principles. With cylinder 1 at TDC and about to start its firing stroke (cylinder 4 valves open), the rotor in the distributor should be pointing towards the pole in the cap that has a wire going to spark plug 1. There's a 'correct' way, but you can rotate the whole distributor through 90 or 180 degrees and it won't matter, as long as the leads are moved to suit.
IIRC, the direction of rotation of the distributor was reversed at some point during the production life of the M10, but not during production run of the E30. Worth remembering if you're sourcing replacement bits, which may have come from older models.

Re: M10 Rotor Arm Position

Posted: Thu Jul 23, 2020 11:20 pm
by martauto
What happened was I replaced the cap and arm and leads and plugs but I believe the cap before was on the wrong way so now it will not run. I know it was fine before so I must go back to basics and work up from there. I need it next week as my 325 cab will be in for the ccv valve being done so I will have a go again at the weekend.

Cheers :cool: :cool:

Mart.

Re: M10 Rotor Arm Position

Posted: Fri Jul 24, 2020 8:22 am
by flybynite
That should be a bit easier then, I thought you'd had the dizzy out, if it is just plug leads and cap, simples

If it has been timed and running before, the No1 plug lead should be next to the mark on the dizzy (you don't even need to get the rotor arm pointing there as you are not timing it) just put the leads on in firing order from there.

Standard 4-cyl firing order I think 1,3,4,2. (I think the M10 firing order 'Zundfolge' is also cast into the cam cover)

dist.gif

As Brian said the M10 turned both ways so no point in believing what you read on t'net.

Nudge the car forward in gear to see which way it turns. It is harder with the E30 because of the bonnet, you cant just grab the front panel and pull it toward you while watching the rotor arm

Re: M10 Rotor Arm Position

Posted: Fri Jul 24, 2020 7:17 pm
by martauto
Hi mate, thanks for the pic, I seem to be 180 out 8O
(not down to me )

Did you say before that there is a "mark" on the body of the dissy where no1 should be
?? ?
We could be getting somewhere now, if the "mark" is no 1 then we will go anti-clockwise (checked with one of my lads today ) in 1342 !!
That pic was Awesome mate !!!!

Cheers :cool: :cool: :cool: :cool:

Mart.

Re: M10 Rotor Arm Position

Posted: Fri Jul 24, 2020 7:29 pm
by flybynite
martauto wrote:
Fri Jul 24, 2020 7:17 pm
Hi mate, thanks for the pic, I seem to be 180 out 8O (not down to me )
That pic may be from an E21 so treat it with a bit of caution

martauto wrote:
Fri Jul 24, 2020 7:17 pm
Did you say before that there is a "mark" on the body of the dissy where no1 should be
The mark is at the end of the big arrow on the pic, just a notch in the edge of the dizzy

Get there in the end :thumb:

Re: M10 Rotor Arm Position

Posted: Sat Jul 25, 2020 5:18 pm
by martauto
Thanks guys for all your input and she now ........................................................................................................lives with a passion :cool: :cool: :cool: :cool: :cool: :cool: :cool: :cool: :cool: :cool: :cool: :cool: :cool: :cool: :cool: :cool: :cool: :cool: :cool: :cool: :cool: :cool: :cool: :cool: :cool: :cool: :cool: :cool: :cool: :cool: :cool:

Out tomorrow winkeye winkeye winkeye winkeye

Mart.

Re: M10 Rotor Arm Position

Posted: Sat Jul 25, 2020 5:47 pm
by flybynite
:thumb:

Re: M10 Rotor Arm Position

Posted: Sun Jul 26, 2020 2:28 pm
by martauto
flybynite wrote:
Sat Jul 25, 2020 5:47 pm
:thumb:
Cheers , ran like a dream, in her for work all next week so should be good fun. :cool: :cool: :cool: :cool: :cool: :cool: :cool: :cool: :cool:

Mart.