It has certainly been messed with as the tufnol washer with the oil holes in it(l/h side of pic 1) is a sun wheel shim/thrust washer for an early diff of the S1, 2 & early 2a flavour which had a bolt on pinion oil seal retainer, Once the oil seal retainer was made integral with the case there were no shim washers used on the sun wheels. Also the crownwheel bolts are 3/8" BSF rather than the later 3/8"UNF.
If the diaphragms are split in the carbs it will be dire to drive, i drove a 6 with a split diaphragm about 2 miles to the workshop and i could have walked quicker.
4 S
D
Was the formula we were tought, S being the cutting speed in feet per minute & D being the job/cutter diameter in inches.
Mild steel 80ft/min, cast iron 60ft/min.bronze 80ft/min,
The body has no effect on the eligibility to retain the reg number and tax status, if the new chassis is like for like then that is allowed as well. Changing the engine would only loose you 1 point. Look at the DVLA or is it VOSA points system for vehicle ID.
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chassis or body shell (body and chassis as one unit - monocoque ie direct replacement from the manufacturer) (original or new) = 5 points suspension = 2 points axles = 2 points transmission = 2 points steering assembly = 2 points engine = 1 point You need 8 points to keep the ID.
That looks like the 6 wheel disco that was built on a Range Rover fire truck rolling chassis, the body was made from 1 x 5dr shell & 2 x 3dr shells. 1 of the 3dr shells was off our 200disco. The builder was a chap called Trevor Adler.
I would say the existing diffs fitted are imperial so swapping the 3.54 innards over wont work as they would be metric.
The front brakes are indeed 3" wode jobbies.
The SLS brake in the stack is an 11".
With the ports blanked you are correct that it wont make any difference when the oil is not hot. But when its hot and the stat opens to divert the oil thro the cooler because it has been blanked off will mean that the oil flow to the engine bearings will stop or be very very reduced, result one toast engine.
IIRC the SWB 2 line master has a single bore size the full length and the LWB has 2 bore diameters along its length so the front/rear balance is different, also the pipe connections are different ways round depending on SWB or LWB.
I would suggest going with the std system as done by LR when they went twin line with the 11" fronts.
In my experience you will find that the bearings will be more prone to rust than the gears, my salisbury front axle when i got it had badly rust pitted bearings and the gears were just dirty and washed clean, it had neen left full of water. I put it down to the steel of the gears containing more chrome in the alloy makeup than the bearings had.
That is complicated.
Not like i was shown by a driver from Red House back in the 70's or by an ex partriot farmer from Staffordshire in the 90's, nice and simples.
Possibly a daft suggestion this.
I was told by a man who did a lot of Range Rover repairs that RV8's used to require the oil pump gears to be primed with petroleum jelly so that when starting the engine for the 1st time they would suck up the oil from the sump, would this also apply to a 300Tdi?