The Holden one is a ridiculous price for something that will rapidly cause problems with that rivet. The red rotor arms from the Distributor Doctor are cheaper and far superior in quality.
Brain fade seems to be following me about. I plugged the electric kettle in this morning but it didn't work. I then realised I'd plugged the air fryer in instead.

Here are 2 distributors from my spares. Both have "Lucas England Patented" stamped on them and both are 45D4's. One is a genuine Lucas to be kept and the other is a cheap and 'orrible Chinese copy destined for the scrap heap (unless anyone wants it, free to collect). There's an obvious difference between them which is hidden in the photo.

Quote from: Alan Drover on Jul 20, 2024, 10:59 AMHere are 2 distributors from my spares. Both have "Lucas England Patented" stamped on them and both are 45D4's. One is a genuine Lucas to be kept and the other is a cheap and 'orrible Chinese copy destined for the scrap heap (unless anyone wants it, free to collect). There's an obvious difference between them which is hidden in the photo.

How do you tell the difference when they both say Lucas on them?

The genuine one (left hand one) has the direction of rotation marked with an arrow and a number stamped on the side, or on a sticker on the opposite side that's hidden in the photo. The Chinese rubbish doesn't.
However a quick visual test shows the very poor quality of the casting on the Chinese rubbish compared with the genuine one. It looks like it's been plastered together.

Two images of my NOS Genuine 45D if it helps.

You can see the number and date code on the label.

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Thank you 

That's what the Chinese ones don't have.

Just a quick update. I got a red rotor arm from the distributor doctor. Unfortunately it's made no difference 
Having sent photos to them to make sure I got the right part, they advised that I do indeed have a Chinese distributor 
Is it possible that could be the cause of my problems?

I'm thinking if going down the route of getting a 25D and having it refurbished maybe? As you all say the Chinese ones are  rubbish so even if it's not causing my problems, I should get shot of it anyway.

I'd say an emphatic "YES." I've found one which is absolutely no good, not even for spares and the Distributor Doctor won't touch them. I don't know why I've still got it. Get a proper 25D and have the Doctor rebuild it. Diffwhine has a load of spares. Worth contacting him to see if he has one

Reading the symptoms, it sounds like the engine is running a little lean when cold. This might be related to the fact that you don't have a working choke. Before spending money on replacing a distributor etc, it might be worth getting the choke working, and trying it with the choke out until it's warm. If this helps (and assuming that it's not actually cold weather) you may want to tweak the idle mixture a little.

Not saying it's not the distributor, but backfiring for me has always been a fuel issue, and this case seems to be engine temperature related, which again, to me, points to fuel not spark (no condenser involved) A working choke is always handy too for troubleshooting possible fuel issues as it gives a quick way to vary the conditions whilst driving.

I'd still get a 25D4 and have it rebuilt. Provided the casting is sound the Doctor can rebuild it. Backfiring is usually caused by retarded ignition timing.

Quote from: jonhutchings on Aug 06, 2024, 11:09 AMReading the symptoms, it sounds like the engine is running a little lean when cold. This might be related to the fact that you don't have a working choke. Before spending money on replacing a distributor etc, it might be worth getting the choke working, and trying it with the choke out until it's warm. If this helps (and assuming that it's not actually cold weather) you may want to tweak the idle mixture a little.

Not saying it's not the distributor, but backfiring for me has always been a fuel issue, and this case seems to be engine temperature related, which again, to me, points to fuel not spark (no condenser involved) A working choke is always handy too for troubleshooting possible fuel issues as it gives a quick way to vary the conditions whilst driving.

Thank you. Replacing the choke cable is on my list to do! The symptoms do continue when she gets hot too.
I will have a tinker about and see how I get on. I think I do need to get shot of the Chinese distributor regardless.

There are 2 types of backfiring I reckon. There's backfiring through the exhaust usually caused by petrol vapour igniting in it, and spitting back through the carburettor. I think the former is caused by retarded ignition and the latter by fuel problems.
Willing to be corrected.

Quote from: Alan Drover on Aug 06, 2024, 02:24 PMThere are 2 types of backfiring I reckon. There's backfiring through the exhaust usually caused by petrol vapour igniting in it, and spitting back through the carburettor. I think the former is caused by retarded ignition and the latter by fuel problems.
Willing to be corrected.

Mine is definitely out the exhaust.

I thought your distributor was a proper one but if the Doctor says not then it's not. He knows his distributors. I'd look for a proper Lucas 25D4 ensuring that the casting is sound and get the Doctor to rebuild it and fit his Pertronix electronic ignition at the same time. I can't be 100% sure but I'm fairly certain that Chinese distributors are all 45D4's.
What carburettor is fitted? Is that Chinese too?