the original engine in my 420G had a longterm mysterious oil consumption issue,
I have reason to believe rings were not fitted or worn in correctly before I obtained the vehicle,
fouls plugs badly, so I decided to remove and OH it, whilst temporarily fitting a replacement motor.
luckily turned out the S2 XJ6 4.2 motor I bought very cheaply off Ebay had been subject to a big $ complete rebuild not many years ago, (I obtained rebuild and dyno sheets via the PPO)
its in now, and running well, but I still need to custom make final version of some throttle parts
that is the single hardest thing I found to do, as the XJ motor has a cable throttle, from the accelerator pedal, while the 420G has a complex system of levers and rotating parts.
the 2 systems must marry up exactly for max-min throttle travel, which isnt easy, and clearance is very tight
to complicate even further, I have a BW8 auto, which has a cable-only controlled kickdown, also needs precision brackets, or the auto trans wont work properly unless cable length adjustment and travel distance is mm perfect
dont think there is any way around buying a manual choke kit, as the mechanism is complex.
I really like it compared to ASC
have spare unidentified non-jag HS6 with manual choke setup, (but missing connecting rod), maybe could use parts for my tri-carb mod
What Taco did you use ?
Not that worried at the moment , but if I decide to fit the engine in the MK2 , that will be on the to do list
On the XJ6 3.4 engine there is 2 threaded holes on the carb side , at the back of the cylinder head , so I took the cam cover off to see if there was a slot , in the back of the cam , for the generator drive , no such luck , I have a generator and the 2 holes line up , that would leave the 3rd hole to sort out or leave , If the cam shafts are the same as the 240 it would not be a problem , as I have 4 of them , plus the cam covers , 2 have a cut out on the back for the generator !
If the tach drive is a problem you could simply plug the hole at the back of the cam and have someone such as myself modify your tach to trigger from the ignition pulses. That would be much more accurate than the original tach-gen system, which generally reads low due to aging magnets in the generator.
the original 420G tach is impulse, same as later XJ, so I retained that
I do not know if they are correct size fit for a MK2.
otherwise Mikes suggestion may be easier, as camshaft and also maybe rear bearing cap & cam cover may need swapping, and as Mike said, if the generator is worn, it wont be accurate…also XJ items can be innaccurate due to failed electronic components after 30+ yrs
Well work on the XJ6 engine is progressing , slowly , may see about the water pump sooner rather then later , as the bottom hose outlet is 2" , the other pumps I have are around 1 3/4 , about the same as the rad connection , so can use a straight pipe all the same size .
Spent a couple of hours fabricating a choke mechanism , for the test bed they will both be cable operated , both being pulled down by the cable attached to the bottom bracket , the 0 rings are just there as a temp fix , to stop the threaded bar moving forward, anyone who pays £250-£300 for a manual choke conversation needs there head looking at lol , made it up with bits from the garage , threaded bar can be changed for a nice s/steel bar, and the nuts , to look a proper job !!
