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Replacment distributor
Posted: Sun Jul 05, 2026 5:23 pm
by Nax
Hi I'm looking to change the distributor on my 1971 1098cc HC minor 1000, I've been offered a lucas 24d 41026K from an 850 mini
Can anyone tell me if it will be suitable for my engine
Thanks.
Re: Replacment distributor
Posted: Sun Jul 05, 2026 5:52 pm
by mobylette
Do you mean 25d? If the drive shaft is the same it will fit.
This may help:
https://www.triple-mregister.org/upload ... 0LUCAS.pdf
Re: Replacment distributor
Posted: Sun Jul 05, 2026 6:11 pm
by svenedin
It will physically fit IF it is a Lucas 25D with anticlockwise rotation but the advance curve will not be correct for a 1098. Any second hand distributor is highly likely to have a failed vacuum unit too. The rubber diaphragm perishes. The vacuum unit is also specific to a particular engine and application; they are not universal.
Stephen
Re: Replacment distributor
Posted: Sun Jul 05, 2026 7:12 pm
by Nax
Yes sorry I mean 25D.
I have a new Powerspark on at the moment but I don't trust it, its very poor quality
Re: Replacment distributor
Posted: Sun Jul 05, 2026 7:21 pm
by svenedin
I agree, both the Powerspark and Accuspark units are poor quality and the micrometer timing adjuster doesn't even function. I tried an Accuspark unit and looking with a strobe the timing wandered all over the place.
If you want the best, go to Distributor Doctor. He can rebuild your original distributor or he can rebuild a Lucas 25D4 that did not come from a Minor 1098cc to the correct specification. He can also supply the correct distributor as an outright sale with no need for a donor unit. Not cheap I am afraid.
If you want electronic ignition and a new distributor I have heard good reports about the 123igntion distributors. These are expensive too.
At one time, Bryan Gostling from MMOC club spares had some NOS Lucas 25D4 distributors. I bought one actually.
The codes for a late Lucas 25D4 1098cc high compression Minor distributor are: 41148 and 41269. There are others but Distributor Doctor confirmed to me that these are definitely correct.
Stephen
Re: Replacment distributor
Posted: Mon Jul 06, 2026 10:26 am
by Nax
Thank you for your advice I'm glad to know its not just me being fussy.
What are your thoughts on fitting a genuine lucas base plate into the powerspark body, would if fit?
Re: Replacment distributor
Posted: Mon Jul 06, 2026 11:38 am
by svenedin
Nax wrote: ↑Mon Jul 06, 2026 10:26 am
Thank you for your advice I'm glad to know its not just me being fussy.
What are your thoughts on fitting a genuine lucas base plate into the powerspark body, would if fit?
I do not know whether a genuine Lucas base plate would fit. The issue is not just the build quality but the advance curves. The distributor contains weights and springs that move outwards with centrifugal force and as they do this they advance the ignition timing. The advance is calibrated to a particular type of engine. The Powerspark will have a generic advance curve. This may be good enough for most situations I suppose but I have never actually seen the advance curve plotted for one of these distributors. Likewise, the vacuum unit is designed to adjust the timing at particular manifold pressures. The most important thing of all is that the maximum advance must not be excessive or pre-ignition (pinking) can occur.
Stephen
Re: Replacment distributor
Posted: Mon Jul 06, 2026 8:10 pm
by stuffedpike20
ESM list one vacuum unit, with push on pipe.
Would this definitely be right for a 1098, or is it just a generic one?
Re: Replacment distributor
Posted: Mon Jul 06, 2026 10:12 pm
by svenedin
stuffedpike20 wrote: ↑Mon Jul 06, 2026 8:10 pm
ESM list one vacuum unit, with push on pipe.
Would this definitely be right for a 1098, or is it just a generic one?
I don’t know. It might good enough as a match. These are not high performance engines after all. If you call Distributor Doctor he will sell you the absolutely correct vacuum unit.
Stephen
Re: Replacment distributor
Posted: Tue Jul 07, 2026 10:35 am
by Mervin
stuffedpike20 wrote: ↑Mon Jul 06, 2026 8:10 pm
ESM list one vacuum unit, with push on pipe.
Would this definitely be right for a 1098, or is it just a generic one?
Looking at that ESM unit, it is a cheap Chinesium generic thing. The same as those fitted to the Chinesium distributor copies. I do have one of the copies but without checking I don't think the mechanical advance weights have any numbers on them either. The Lucas weights have the degrees of advance stamped on them. There are different springs too. It will work but is not necessarily correct.
The original Lucas units have a code number stamped on them which denotes the degrees of vacuum advance.
Re: Replacment distributor
Posted: Wed Jul 08, 2026 6:39 am
by stuffedpike20
I could buy six Chinese distributors complete with rotor arms, points, condensers, caps and vacuum units for the price of one D.D. reconditioned distributor.
Just saying, that's all.
Re: Replacment distributor
Posted: Wed Jul 08, 2026 8:20 am
by svenedin
stuffedpike20 wrote: ↑Wed Jul 08, 2026 6:39 am
I could buy six Chinese distributors complete with rotor arms, points, condensers, caps and vacuum units for the price of one D.D. reconditioned distributor.
Just saying, that's all.
You could. Or you could support British businesses and buy the best. Martin Jay (Distributor Doctor) spent a long time finding British small businesses who could make ultra-reliable condensers, rotors etc. I must admit that when I had my distributor rebuilt by DD I was a bit shocked by how much it cost but I had tried a Chinesium distributor and I was very unimpressed.
Stephen
Re: Replacment distributor
Posted: Wed Jul 08, 2026 8:55 am
by stuffedpike20
svenedin wrote: ↑Wed Jul 08, 2026 8:20 am
stuffedpike20 wrote: ↑Wed Jul 08, 2026 6:39 am
I could buy six Chinese distributors complete with rotor arms, points, condensers, caps and vacuum units for the price of one D.D. reconditioned distributor.
Just saying, that's all.
You could. Or you could support British businesses and buy the best. Martin Jay (Distributor Doctor) spent a long time finding British small businesses who could make ultra-reliable condensers, rotors etc. I must admit that when I had my distributor rebuilt by DD I was a bit shocked by how much it cost but I had tried a Chinesium distributor and I was very unimpressed.
Stephen
Good points well made.
Some owners, however, can't afford the prices. I suppose we should be grateful that there are cheap alternatives available too.
They are probably keeping a lot of cars on the road that otherwise would not be.
Re: Replacment distributor
Posted: Wed Jul 08, 2026 9:09 am
by svenedin
stuffedpike20 wrote: ↑Wed Jul 08, 2026 8:55 am
svenedin wrote: ↑Wed Jul 08, 2026 8:20 am
stuffedpike20 wrote: ↑Wed Jul 08, 2026 6:39 am
I could buy six Chinese distributors complete with rotor arms, points, condensers, caps and vacuum units for the price of one D.D. reconditioned distributor.
Just saying, that's all.
You could. Or you could support British businesses and buy the best. Martin Jay (Distributor Doctor) spent a long time finding British small businesses who could make ultra-reliable condensers, rotors etc. I must admit that when I had my distributor rebuilt by DD I was a bit shocked by how much it cost but I had tried a Chinesium distributor and I was very unimpressed.
Stephen
Good points well made.
Some owners, however, can't afford the prices. I suppose we should be grateful that there are cheap alternatives available too.
They are probably keeping a lot of cars on the road that otherwise would not be.
Fair enough, it gives choice. Yes, it is expensive to have a distributor rebuilt and calibrated but in my own case my distributor had not been overhauled for over 50 years. That's a very low cost per year! If they can get the parts some owners could rebuild their distributors themselves which would reduce the cost but they are unlikely to have access to equipment to check the advance curve is correct. If they use like-for-like parts from a reliable source it should all be correct anyway.
Stephen
Re: Replacment distributor
Posted: Wed Jul 08, 2026 11:40 am
by stuffedpike20
I have posted before how one minor I owned performed better than all the others. Over the years I have put 13 minors back on the road. Some of them I did not own, or drive for long....just buying them, welding them , Mot ing them and then selling them.
I don't know why the 'good' one was so good. Could it have been the only one with a decent distributor? Unlikely, I would have thought. But who knows?
Re: Replacment distributor
Posted: Wed Jul 08, 2026 11:43 am
by svenedin
stuffedpike20 wrote: ↑Wed Jul 08, 2026 11:40 am
I have posted before how one minor I owned performed better than all the others. Over the years I have put 13 minors back on the road. Some of them I did not own, or drive for long....just buying them, welding them , Mot ing them and then selling them.
I don't know why the 'good' one was so good. Could it have been the only one with a decent distributor? Unlikely, I would have thought. But who knows?
I don't know. Maybe it had a fancy engine that looked entirely standard from the outside?
Stephen
Re: Replacment distributor
Posted: Wed Jul 08, 2026 12:35 pm
by les
Yes can be a dilemma paying for expensive parts verses cheap. I look at it like this, if we go down the cheap option, apart from quality issues, the companies selling better, although more expensive parts, are not likely to get as much custom, so don’t continue those lines. Our loss. Likely that’s why there are now some inferior parts around that often don’t fit. One of the reasons I’d be very reluctant to take on another project.
Re: Replacment distributor
Posted: Wed Jul 08, 2026 2:40 pm
by ManyMinors
Well said Les. And that is the reason why we can no longer purchase brake master cylinder or wheel cylinders made by the original manufacturer and why Mintex brake shoes stopped being available a year or two ago etc etc

Re: Replacment distributor
Posted: Mon Jul 20, 2026 11:39 am
by stuffedpike20
Moss have got vacuum units in stock. The part number they give is 517251.
Is that the right unit for a 1098 minor?
Re: Replacment distributor
Posted: Mon Jul 20, 2026 2:11 pm
by geoberni
stuffedpike20 wrote: ↑Wed Jul 08, 2026 11:40 am
I have posted before how one minor I owned performed better than all the others. Over the years I have put 13 minors back on the road. Some of them I did not own, or drive for long....just buying them, welding them , Mot ing them and then selling them.
I don't know why the 'good' one was so good. Could it have been the only one with a decent distributor? Unlikely, I would have thought. But who knows?
If you were simply turning them around for sale, you've got no idea what alterations might have been made, the engine could have been significantly tuned or otherwise tweaked.