The Saga of TC 4332 (Chapter 5)

We last reported on Les Hancock’s rebuild in June (Issue 18). At the time he had reached the rolling chassis stage and his closing remark made in the article was “It should be easier from here up, I wish!”

Read on to find out whether it was in fact easier!

Now having a rolling chassis I was able to bring the engine, still with gearbox attached, into the rear of the garage. My original intention was to simply clean the engine and repaint it in a dark grey as it was originally. I separated the engine and gearbox and decided to check the engine to ensure all was well; no point I thought having already spent so much money – more about that later – to reinstall the engine with possible future problems. I was very pleased I made the decision to check the engine… as you will read further on!

I carefully dismantled the engine, removing the head, the sump and firstly inspected the camshaft. The lobes were heavily pitted, as were the camshaft followers, typical of parts receiving limited lubrication. I decided to remove the camshaft for better inspection and measurement. The middle bearing was removed and it was here I received a shock – the bearing had been installed the wrong way around, the locking screw being located in the oil way. The oil from the gallery was therefore meeting a dead end. It says something for the sturdiness of the XPAG that it has probably run in this condition for many miles, relying on oil sprayed principally from the con rod bearings.

I could not remove the rear camshaft bearing and therefore had to remove the rear camshaft core plug. I was then able to push the bearing out. I withdrew the camshaft through the front bearing, which I also removed using a “Brummagem Screwdriver” (a hammer).

I set the camshaft in the vice secured by the centre bearing which is in two halves, held between two softwood blocks. I then, checked the lift on each lobe using a digital micrometer. The rocker ratio was measured at approximately 1.42:1; the lift at the lobe was multiplied by this value, hopefully showing the valve lift. The valve lifts varied between 7.01mm and 7.56mm. This gave between 87% and 94% of the quoted value of 8.03mm.

Due to its worn condition and the centre bearing I decided to replace the camshaft – again flashing pound signs! – and obtained a fast road camshaft from Peter Edney along with the front, rear and middle bearings. I also purchased a single new follower with modifications to provide better lubrication to follower base and the camshaft. I checked its dimensions and weight, all being very close to the originals, this may seem pernickety but I have become suspicious of all replacement parts.

Quite rightly so! Ed.

The pistons were removed, followed by the crankshaft. The bores were measured using a digital micrometer at four locations corresponding to north, south, east, and west. All bores varied between 67.44mm and 67.97mm indicating an oversize of 0.060” giving a capacity of 1300cc approximately. I decided to replace only the piston rings. A later cleaning of the piston heads revealed 67.98mm stamped on them confirming the micrometer measurements.

The main crankshaft journals were measured at ten locations, all three averaging a value of 51.47mm, indicating a grind of 0.5mm or 0.020”, this figure being confirmed on the removed main bearing shells. These were generally in good condition although some had locally pitted surfaces. I decided to replace only the bearing shells.

The con rod journals were measured in the same manner as the mains and these averaged at between 44.94mm and 44.96mm, indicating standard journals (45mm). I thought it odd that the con rod journals were standard, whilst the mains were +0.020”. the engine may have run a main bearing in the past. I decided to replace the con rod bearing shells.

The head was inspected and it was noted that the rockers had noticeably worn tips at valve) and some lateral movement was noted between the rockers and the rocker shaft. The head had not been prepared for unleaded fuel so it was decided to send the head for conversion and general refurbishment. New valves and guides were fitted, along with a new rocker shaft, the original being badly worn and showed signs of oil starvation. The rocker arms were re-bushed and re-metalled; the head is now ready for fitting.

The engine block was taken to the local engine shop at Salford Priors in South Warwickshire and cleaned, much muck coming out of the waterways. The new camshaft arrived with new bearing set and a new rear camshaft core plug. The plug was inserted followed by the camshaft front and rear bearings, extreme care being taken to ensure the oilways were aligned. The camshaft followed with the split centre bearing, all went well and the locking screws tightened.

With the camshaft came new main crankshaft bearing shells at +0.020”, together with new standard con rod bearing shells. The next problem was about to rear its head. On trying to fit the centre crankshaft thrust bearing shells they would not locate onto the crankshaft bearing, clearly being oversize.

Contact was made with the supplier who advised it was necessary to file the thrust faces of the shells until they located onto the crankshaft. This was duly done and the crankshaft inserted.

At this point the rear crankshaft oil thrower cover was located onto the locating pins and lightly tightened. Having read of the problems with this seal so well laid out by Eric Worpe, I checked the side clearances and found that the gap to the crankshaft on one side was 0.002” and on the other 0.006”, a clearance of 0.003/.004 being recommended.

Careful filling of the pin holes in the aluminium cover enabled the cover to be eased to give 0.003”/0.004” each side and the cover tightened. The crankshaft bearing caps were placed and the nuts torqued to 85Nm – this immediately locked the crankshaft solid.

I felt I was starting to get out of my depth at this point and took the engine and the crankshaft problem to the engine shop. They called me later to confirm the problem and advised they thought that either the bearings were oversize or that the thrust face radius was incorrect, they would check and advise me and here the matter rests at present.

The TC being late 1947 had a firewall (scuttle) and foot ramp originally painted light grey. After several emails with John James he advised his scuttle and foot ramp were a pale green. Mike Sherrell suggests that the original light grey colour does with age show a significant green hue, but suggests that the original colour was a light grey, light aircraft grey being a good match. A sample was obtained and the battery box lid sprayed as a test, as described the colour was a light grey with a noticeable green hue.

The scuttle and foot ramp had all unnecessary holes filled, were straightened and sprayed light aircraft grey, the transformation being a revelation. The foot ramp and scuttle were joined and are now ready for bolting to the body tub.

Due to the cost of the TC so far I have had to slow down and budget my expenditure, spending fixed amounts each month, to say I have become disillusioned at times is an understatement, but the moods pass and I am determined to finish the car.

Leslie Hancock
Lestc4332(at) {substitute @ for (at)}.

Ed’s Note: Les is in need of an oil pump for his engine. Advertising for one has not borne fruit to date. If you can help, please e-mail him.