My first idea was to leave the clutch unit unrestored, because there was still some original paint available and he did’t look so bad. After inspection I saw a lot of rust inside (Springs and clutch plate) and therefore decided to restore the clutch unit as well.

The original clutch unit which was mounted on the flywheel

So first I disassembled everything (be careful with removing the three nuts, there is a lot of pressure due to the twelve strong springs). Cleaned everything with glass bead blasting and sprayed everything with a new fresh layer of paint. I used special paint for the parts who can become very hot (< 800℃)

The original paint on the springs, who will deliver the pressure to the clutch plates, where  not visible anymore. But in the documentation is stated the they should be painted yellow.

The restored clutch unit, ready to be mounted

I didn’t know if it was really necessarily but I placed the cover on the same location as it was originally. During the assembly I noticed that the pressure plate has been balanced in some way (In the second picture you can obvious the have drilled 7 extra holes to remove some material).

Before assembly of the engine could start all bearings are measured:

• Mains bearings (6/100, still within specification)
  To prevent honing the crankshaft(I can only be done twice, and it will get less riged) I accept the play as it is.
• Thrust washers (with one STD and one oversize 11/100)
• Big-end bearings (4/100, still within specification)
• Small-end bearing (No notable play)

Original uncleaned bottom view of the crankshaft

All separate parts are thoroughly cleaned and the following parts are bought new:

• New main bearings (STD)
• New big-end bearings (STD)
• New thrust washers (STD + oversize)
• New piston set (complete with 4 rings, gudgeon pin and circlips)

All cleaned and new parts needed to mount the crank shaft and pistons

Remarks:

• Don’t forget the oil sealing ring at the rear block before the crankshaft is mounted.
• Mount the bearing so the indicators will match (they are all numbered and the engine block also has these numbers stamped into the casting) Numbers should be kept at the inlet side.
• The pistons are number from 1 until 6 starting from the backside of the block
• The piston numbers are stamped into the connection rod and the big-end bearing cap
• The piston numbers should be readable from the exhaust side
• The compression piston rings should be mounted in opposite direction 0 and 180 degrees. I also mounted the oil scrapper rings at 90 and 270 degrees.
• When piston 1 and 6 are in the TDC position the distributor shaft should be positioned at 5 to 5. The distributor shaft will make a half rotation when the crankshaft has made one.
• When the timing chain is connected to camshaft make sure the distributor shaft is positioned as shown on the picture.
  (Remark the notch is positioned left from the middle at 5 to 5)

Because I found some pictures, original made in jaguar factory with painted text, I painted the “Jaguar” logo and the text “3 1/2 litre” in white.
Bellow the engine block with the pistons and crankshaft completely mounted.

Engine with the crankshaft and pistons installed

Crankshaft, bearing caps and connecting rods installed 

Original dynamo removed from engine

Because the above dynamo, mounted to my engine, was originally from a XK120 I needed to look for the correct one.

This dynamo has a brass identification plate with the following information:
Lucas 22452B, GC51, C45PVS/5, 12V, 53

The dynamo I needed should have the following numbers:
Lucas ,22462B, GC51, C45PVS/5, 12V, 56

An other XK140 restorer in my neighborhood offered me a deal I couldn’t refused.
Exchange mine xk120 dynamo for a correct, fully restored, xk140 dynamo and give him a small reimbursement for the parts he used for the restoration.

All parts needed for rebuilding the dynamo

All separate parts are again sandblasted and pained black so they all look again as new.
To prevent rust, and make it easier to remove them in the future, the bolts are also painted black and mounted with a little bit tectyle.

Dynamo and engine brackets mounted on the engine

Cilinder Head

After all valves where removed and cleaned it was clear, that from the to heads (24 valves), a good set of valves could be combined. Some of the valves show corrosion damaged and can’t be used anymore. The corrosion in the water ports are not to bad and can be left as they are now.

One tappet guide should be replaced because it is cracked (became visible  after cleaning)

Because one of the mounted camshafts (outlet) where from a XK120 (less valve lift) I bought an other one from a jaguar MK2 (C13081) Together with the mounted inlet valve is C13080 we have a matched set again.

Cilinder Block

After removing all main bearings and the crankshaft we could start removing the pistons.
Because the block has not be moved for over 46 years this was not a easy job. The first three pistons could be removed quite easily but the last three where deadlocked. After I applied penetrating oil and wait a couple of weeks, I managed to knock them one by one loose with a block of wood and a heavy hammer.

One of the six cylinder walls was badly damaged by corrosion.

All parts needed to rebuild the head and block are thoroughly cleaned and sorted, ready for the machinery.

Today I brought the cylinder-head and cylinder-block to “Rombouts revisie” in goirle.

The measured clearance:

• Crankshaft STD with 15/100 mm clearance
• Inlet Camshaft STD with no visible play
• Outlet Camshaft STD with no visible play
• Piston 1 STD with 15/100 mm clearance
• Piston 2 STD with 15/100 mm clearance
• Piston 3 STD with 15/100 mm clearance
• Piston 4 STD with 15/100 mm clearance
• Piston 5 STD with 15/100 mm clearance (after drilling to 75/100 mm still corrosion visable)
• Piston 6 STD with 25/100 mm clearance (after drilling to 50/100 mm still corrosion visable)
• To match play on the valve guides
• Valve seats are worn and will be replaced by unleaded fuel types

.010″ = 10/1000″ = 0,25 mm = 25/100 mm
.020″ = 20/1000″ = 0,50 mm = 50/100 mm

Before the actual revision started they executed a cylinder head water pressure test to discover possible water leakage. (Due to the visible corrosion in the cylinder head) The conclusion was that it already started to leak inside combustion chamber 5 at a very low water pressure level. The advise was to look for a different cylinder head due to the high corrosion level in combustion chamber 4, 5 and 6. So I brought my XK120 head for the same test and although the water channels where no so good, the combustion chambers where much much better. Because the head between the XK120 and XK140 are technically equal (except for the number stamped into the casting) I decided to take the XK120 head.

The valves from both heads (24 in total) are not usable anymore because;

• 10 pieces are damaged by corrosion
• 7 pieces are shortened to compensate the excessive valve seat wear.

Work for the revision company:

• Re-sleeve cylinder wall 5 and 6
• Drill all cylinders to +020
• Flattening of the cylinder block
• Water pressure tests on two different XK cylinder heads
• Replace all valve seats with unleaded fuel types
• Replace all valve guides
• Flattening of the cylinder head
• Welding all damaged water channels in the cylinder head (12 x)
  The discoloring around the water channels shows what has been welded

In the mean time I ordered the following new parts:

• 6 Pistons oversize +20
• 6 inlet valves
• 6 exhaust valves
• Crankshaft bearing
• Thrust bearing
• Big end bearings
• Camshaft bearing
• Bottom gasket set (including oil seals)
• Top gasket set (including oil seals)

All preparation has been finished (10 october 2014), the assembly process can now be started.