THE BIG WHITE CLOUD or - "How to rebuild your V12 without a heart attack by Jonas Ewe

The Big White Cloud in the mirror was too big to ignore, it obscured all the rush hour traffic behind. Every molecule of hot water vapour condensing perfectly in the cool sunny April morning came from my Espada and was seen by the driver of the Aston Martin V8 behind me. Score : Aston Martin 15 points Lamborghini 0 points. - how embarrassing!

A quick check showed that the head gasket on the right cylinder bank had blown. No water in the oil, so I nursed the car the 300m back to the parking area at work. The feeling was the opposite of wining the pools.

The left exhaust had been slightly smoky since I bought the car, so I decided to renovate the engine. I asked John Gorbould and Kit Constable Maxwell what might be involved in skill, time and money. -"About 14 - 16 working days, £2000 in parts and don't forget that you need 8m2 of lay-out space".

I was confident I could do the work myself. I had tuned and rebuilt a couple of Volvo engines in the sixties which had been very nice and reliable on madly fast and deafening trips between Sweden and Switzerland on unrestricted German autobahns. I had one wild Volvo 122S fitted with a Judson supercharger imported directly from USA. Torque from 500 revs onwards. That one was not a wolf in sheep's clothing. rather a cheetah dressed in moleskin. It out-accelerated everything to about 50 - 60 mph in the 'Green light GP'. Sorry, I am getting nostalgic - back to the Lamborghini engine. The other reasons for doing the renovation myself was pure enthusiasm and financial necessity.

I had no space where I could lift the engine out so the car was transported to Portmans in Brentford where the engine and gearbox were taken out and degreased. The "Carozzeria sensa motore" towed back to the garage and the engine and gearbox taken to my workshop. A sturdy V thick platform on four heavy duty castors was built so the engine could be moved around and kept out of the way during normal working hours. The engine looks big installed in the Espada. but truly massive in a crowded workshop.

The workshop manual was read many times before I started, to avoid mistakes and wasted time. This article is not a new manual. but you must know where every bit comes from and where and how it will go back. If you haven't re - built any engines, don't start with a 3929cc DOHC V12 Lamborghini engine unless you are very brave and preferably filthy rich too. You must have a good. clue about what you are doing.

Dismantling was easy. The carburettors and manifolds had already been taken off.

I had stocked up with many small plastic bags with labels and now attacked the first of many M6 dome nuts that are sprinkled all over the engine from camshaft covers to the sump like diamonds at a society wedding. First off was the water pump which is engineered like a miniature water turbine and beautifully cast. The oil pump and filter are in the same league. no off - the - peg components here. Once the oil pump is off you get your first sight into the dark innards of the machine with cam drives etc.

The pleasure of renovating and working on the Lamborghini engine is in no small part visual. As you can see in the books, the engine is a beautifully structured object in both visual and engineering terms. Unfortunately you don't see very much of it in the cramped conditions of the car. The carburettors are compensation for the hidden exhaust cams and manifolds.

More M6 dome nuts are attacked and the cam covers are off. By now I had no doubt in my mind that Mr. Bizzarini. the engine designer. was an M6 dome nut fetishist, be warned. You may think it is simply "mind over matter" and that a dead object like an engine can't possibly do anything to you. How wrong you are! The M6 nuts are just the first line of defence to wear you down mentally. It is the engine's (and Signor Bizzarini's ?) way of checking if you are determined enough, to put doubts in your mind. to force you to think "Do I really know what I am doing ? Shouldn't I really put it all back together before I have made a complete mess of it ?'

'Well, well, you have been warned is the engine's clear message as I proceed to split the two duplex chains for the camshaft drives. Del Hopkins who wrote the workshop manual has conspired with the engine and does not mention the next ingenious innocent looking booby trap the engine has in wait for you.

Anybody who has split a bike chain knows it is easy. You loosen a little clip and a link plate making sure not to drop them into the engine. (I am not that stupid). However the innocent amateur like me now pushes out the loose link with the two pins and - CLICK, gravity does the rest! The link plate in the MIDDLE of the duplex chain falls into the deep dark depths of the engine. John Gorbould had warned me about this little trap, so I was prepared. The trick is to push in a short piece of wire when you take out the studded link. The duplex chain can get stuck in the sprockets, but a piece of thin aluminium sheet between the chain and the sprockets makes them easy to remove and install later.

The engine now gives you some breathing space. The camshaft bearing caps are held by normal nuts. You can check how worn the camshaft lobes are by feeling on top of the lobes. if you feel a sharp edge on the otherwise smooth surface the cam is worn and further investigation may be necessary to determine the extent of wear. No problems in my case, a slight edge on one lobe was removed with fine (400) emery paper.

The engine starts fighting back with heavy artillery. A total of 28 big dome nuts now have to be unscrewed to get the heads off. I win - heads off - and see the top of the slightly domed pistons and the hemispherical combustion chambers. All blacker than a Welsh coal mine.

The cams are taken off and the valve cups come out easily with the help of a magnet covered.with thin cloth to avoid scratching. Just a hint here. There is no need to use the contraption shown in the workshop manual to remove the valve springs. A normal heavy duty valve compressor with a tube on the handle to give better leverage and control is OK. The magnet is also handy to remove the small collets on the valve stems and the steel washers between the valve springs and the head. Count them when you put them in the bag! - Count everything when you put it into the bags !!!!

I turn the heavy block around until it's vertical and unscrew the ever present M6 dome nuts holding the sump, which is another beautiful sand casting. I had finally won the mental battle over the engine when the last M6 dome nut was put in a plastic bag. I guess there are about 50 - 60 dome nuts.

When the sump is removed and the block turned upside down you finally get a good view of that famous all - machined crankshaft held in 7 bearings and the 12 big ends attached to it. It is really impressive stuff and a pleasure to see. but marred a bit by the discovery that half the mesh on the oil suction was covered by gasket cement. Gasket cement is cheap but that does not mean that you have to flush the engine with it. When all pistons had been removed I gave the flywheel and crankshaft a spin. It spun effortlessly for some time as if there was no friction.

Everything was now dismantled, the storage space full with valve covers, heads, valves, pistons. starter, manifolds, Webers. cams, crankshaft etc. etc. and many small plastic bags with labels. The cleaning started and compressed air is a must. The messiest job is cleaning the heads. Remember that aluminium is soft, so easy with the wire brushes etc. and watch those valve seats. The valve stems were thick with deposit from burnt oil seeping through the worn valve guides, hence the smoke. What baffles me a little bit is the absence of valve stem seals. 1 wish I knew why.

Inspection showed that one piston had been damaged for a while. The top piston ring groove had been squeezed in so that the ring could not move freely in it. No other signs of problems apart from the blown head gasket. All bearings were perfectly grey without the slightest scratch. After everything. is cleaned you can see that all ports and the combustion chambers are polished and air flowed like a highly tuned competition engine.

The camshaft has a duration of 188o and overlap of 64 o i.e the same as a highly tuned 4 - cylinder would be with the power probably coming in at about.4000 rpm. You know the sort of car that goes Blurp-blurp-spit-blurp-blurp-blurp-spit-blurp-4000 !1 we-ee-eeeeeee.

But because it is a V 12 it is more civilised.

When the Lamborghini V12 was introduced it was the closest you could come to an off-the-peg Formula 1 engine. Remember that Ferrari's V12 of the day only had one OHC per cylinder bank. !

Back to the heads! To remove the guides you have to heat the heads to 140 o c which is done in an oil bath or oven. not by heating the head with a blow lamp. which was suggested by two reputable engineering firms. Del warned against this because of the risk of distorting the heads, so in the end I followed his advice and let him send the heads to Cosworth to have the guides replaced at great expense. I sent the block to be honed, the crankshaft and new clutch to be balanced after the flywheel had been resurfaced. I bead blasted the cam covers and had them anodised. I think it is a shame to paint them black (the crackle finish is supposed to disperse mechanical noise better.) The exhaust manifolds were also bead blasted and sprayed with black VHT paint. In the meantime I checked the weight of all connection rods and pistons. The new piston and one con-rod had to be lightened a couple of grams. The rod had probably been replaced in the past without checking the weight (by the gasket cement maniac ?)

I finally got all the bits and pieces back and rebuilding started. I an not exaggerating when 1 say that the work is straight forward and not difficult. You of course, have to be clean, read the manual and do what it says slowly without shortcuts. Check and re-check what you are doing. No special tools are required but you have to modify some slightly. Bend a ring spanner to get at nuts holding the inlet manifolds and grind a socket to get a good grip on the big end nuts.

My biggest problem was to avoid getting impatient. If there is not 12 of everything it is 24 or 48 of each. Re-building the V12 is like rebuilding three 4-cylinder engines simultaneously, so each sequence takes time, much more time than you think. Don't rush things, don`t do things to a deadline. Oil everything liberally during reassembly.

Take care to establish the top dead centre of the No.1 piston. The marking on the fly-wheel was not reliable. Mine was one cog wrong. This is very important because you set the camshafts in relation to the T.D.C. and the ignition of course. Get that wrong and you lose power. In my humble opinion, the correct setting of the cams and ignition is probably the most important factor in the whole rebuild.

When the engine was finished I checked the float levels in the carbuettors. They were not correct. It is not only the closing point of the fuel valve which is important. The maximum opening is also important because if the float opens too much it may get stuck with flooding of the carburettors as a result.

The engine and car were finally taken to Portmans who married the two and also checked and re-weighted the distributor for 4 star instead of 5 star petrol. A new distributor cap replaced the old cracked one. They also discovered that the wrong distributor arm had been used!!!!

Engine installed. ignition set, exhausts and electrics connected and filled with 14 litres of oil and 14 litres of water. The Espada was ready to start. I had instructed Portmans not to start it without me. It was late afternoon when I was summoned to their workshop, so everybody was staying to see if the amateur rebuild would start. The electrical booster was connected to save the battery. Tick. tick. ticlc. tick. tick the petrol pump started to fill the 6 float chambers of the 40DCOE carburettors. Accelerator pumped a couple of times. then a further step on the ignition key and the starter began working slower and harder than before on the stiff new piston rings and bearings. The engine finally showed life in a couple of cylinders when I heard loud bangs!!! - My heat sank. it sounded like a lots of money job for a second before I discovered that Del was banging the body hard with his hand and a big smile as wide as the Grand Canyon on his face. Puh. close, but no heart attack this time.

The engine was running on all twelve cylinders when I again discovered The Big White Cloud behind the car. It was not just the normal cold start condensation. This was real steam, I had seen it before ! Is there a doctor in the audience? ! " The heart was in my feet and not pumping.

Where did I go wrong ?

- Did I not adjust the torque wrench tightening the head nuts ?

- Had I not checked the studs in the block ?

- Was the head warped ?

- The cylinder liners should not have protruded as much ?

- The cams were out ?

- Had I forgotten to put in the head gasket ?

- I was speechless and tried to draw Del & Co's attention to the existence of The Big White Cloud. How could they possibly not see it ? !! Were they not skilled mechanics ? More big smiles - they enjoyed every second of my suffering. "Oh the steam? Thats from water in the silencers which haven't dried out after the head gasket blew, that will go away." and so it did after 10 - 15 minutes.There is nothing like true professionals when it comes to taking the mickey out of amateurs.. "You have done a good job !" said Del and my suffering was over and my heart returned to its normal pace.

At first Del & Co did not want to release the car. Possible fuel leaks, water leaks etc. My wallet was still shell shocked and had suffered enough. so I took the "risk' and drove off into the sunset.

Running in the engine at a max 3000 rpm during 500 miles eased up the engine. I had to lower the idle and retune the carburettors a couple of times. 1 think that the more vare and precision is taken to adjust the linkages the smoother the engine runs and without flat spots. The rebuild was done during the summer of 1989 and the engine runs more smoothly than ever after Portmans tightened the duplex chains after 2000 miles.

Well that's it folks.

If you have rebuilt simpler engines without trouble do not hesitate to rebuild the V12 but take it easy and be sure you have the money for spares - £4000 comes closer to the mark if you.have to replace many wom parts.