2.25 petrol not running well

[autorover1]

I was at a car rally this last weekend & a RSR member had a total ignition failure on his early P4 6 cylinder . We eventually found it was a crack in a red rotor arm & the HT was  shorting to the distributer spindle . Managed to get it running with some  gasket cement and a plastic "washer" as an isolator pushed up inside the rotor.

[alex1987]

Thanks Alan. I have been looking on their website.
Are you able to point me in the right direction of which part number I need or am I best to call them? Although I have had my series a number of years, I am a novice when it comes to knowing what's what with model numbers etc.

[Alan Drover]

Just tell them what distributor you have.

[diffwhine]

Just tell them what distributor you have.

And if you aren't sure, just take a photo and one of us will identify it for you.

[Alan Drover]

Somewhere on the casting is a number. It should be a 25D4. Presumably it's a genuine Lucas and not a nasty Chinese copy.

[alex1987]

Thank you. Here's a quick photo. If it's no good to identify from that I will have a look for some numbers when I get a chance. I don't know if it's genuine or not as it's not something I have replaced.

[diffwhine]

Need to double check that. I think it's a later Lucas 45D distributor or something very like it. Can you pop the distributor cap off and take a photo of the points/contacts?

[Wittsend]

Pretty certain I know what it is ...

Can we have a picture from the front and one with the cap off showing the rotor arm and base plate.

Whatever - that doesn't appear to be a Chinese electronic distributor.


-25D

[diffwhine]

If it is a 45D, I'm awash with Lucas points, condensers caps and probably genuine rotor arms for those. Might save you a few pfennigs if you want to go down that route.

[Alan Drover]

Definitely a 45D4, no adjustable vacuum advance. What's the number on the casting?
Diffwhine I could do with a cap please.

[Alan Drover]

Definitely doesn't look like a Chinese copy either. I've got one somewhere bought in a mindless moment (emergency) and none of its parts are of any use whatsoever and the Distributor Doctor won't touch it so it's on its way to the scrapheap.
I've got a proper 2.5 45D4 as a spare.

[alex1987]

Glad to hear it's not a Chinese knock off! I'll have a look for some numbers on it later.
Thank you.

[Alan Drover]

That large rivet on the rotor arm is a definite source of problems. You should be able to turn the rotor arm a fraction anticlockwise and it should spring back proving the bobweight springs are working and if it's a Series 3 distributor the serial number is 5069. If not the Distributor Doctor can rebuild it to suit your engine if you give him the full details of it.
At least get a proper rotor arm and see if there's an improvement.

[Wittsend]

You definitely need to get rid of that rotor arm. If it's not the source of your troubles it soon could be.


You need a rotor arm as seen at the right hand end of this row of arms, labelled ? ? ? ...

Preferably a red arm from the DD.

I see you have the PowerSparks electronic ignition unit, it shouldn't give you any problems.
I also see there's a bit alloy corrosion and white dust - the dizzy body needs a good wipe down.
Inside the dizzy, and under the base plate it should all be clean as a Swiss watch workings.

The Lucas D45 dizzy is sort of OK and is/was not as good as the correct Series 2 Lucas D25 dizzy. The 45Ds were a Series 3 fitting.
With the 25D you have an advance/retard adjusting screw which makes fine tuning of the ignition a dodle.
With the D45 you have to release the clamp and "guess" how far to turn the dizzy.

-25D

[Alan Drover]

Wittsend, as the distributor is a 45D4 shouldn't the correct rotor arm be the red one on the left which is the correct one for a 45D4? The rotor arm in the photo is definitely the wrong one for a 45D4. The left hand one is what is fitted to my 45D4's, even the rubbish Chinese copy (which doesn't have the red one).
Open to correction if wrong.