The new 123Ignition distributor that I bought will not seat all the way down in the shaft drive dog. I also tried to install another Lucas distributor and that would not fit either. The existing one fits. The reason I believe is that the shaft drive for the distributor drive dog is not perfectly concentric with the shaft. It’s difficult to see in the photo but it’s closer to the shaft and the bottom than at the top. The existing distributor has a partially broken upper seating ring which I assume lets it seat easily. Is there any way to adjust the drive shaft for the distributor drive dog? This is the original engine for the car.
FWIW, looks to me like the drive dog offset is greater on the dizzy than it is on the crankshaft gear-driven shaft…I’ve heard Jag went to a larger offset on the later engines, but my 140 has a very small offset…just like the one pictured in the first photo. A bottoms-up view of that dizzy would make it easier to tell…
Hi Andy…try slackening off the pinch bolt and levering it apart a bit and make sure the other bolt is loose so the plate can move around while you slot the new dizzy in… Steve
There’s suposed to be a cork seal that fits under the flange at the bottom of the dizzy. The flange is partly broken on your dizzy and there is no cork seal.
These seals can make fitting a distributor difficult, especially when new as they are a very tight fit.
Either turn the whole assembly through 180 degrees, or if you want to retain the orietation of the wires on the cap, consult the 123 installation instructions to see how to turn the drive dog through 180 degrees.
Thanks for your help guys, I tried everything suggested with no luck. I also have a spare Lucas distributor and tried to gently tap it down but it just got stuck and I had to pry it out. The original one with the piece of the collar missing goes in just fine and works great so I’ll live with it as it is and try and return the 123Ignition distributor.
Hi Andy…dont you want to find out what the problem is? just incase you need a new dizzy…how far in will the new ones go…is it the o ring stopping it going further… Steve
Hi guys, thanks again for your help and advice. Well I tried it again and this time it went in all the way, maybe it was the O ring because it was very hard to remove. So it does fit after all, however when I turned on the ignition the tach shot up to 2000 rpm without the engine running, so I’d need to have the tach recalibrated. So I’ve decided to be old fashioned and stay with the points.
