Engine Rebuild.. What me? !!!!

When we bought the boat we knew the engine was not perfect and Paul King had advised us that whilst the compression was not 100% it could have been a lot worse. We ran that first season without any problems so last year we didnt think that matters would have deteriorated as we had looked after the engine and had another service.

Things did take a turn for the worse when we discovered wood shavings in the fuel line - yes it was me folks. I had used a wooden dip stick which upon extraction had caught on the lip of the fuel intake and shaved a sliver off each time (without my noticing). The shavings proceeded to slowly block the supply line, this in turn had been the beginning of the end. At the end of our holiday August 1999 the engine finally died, fortunately we were back in Bradwell, and we were one of the first to be craned out for the winter season!

Ive never even looked at a diesel engine until we bought Osprey, so it was with some fear and trepidation that I embarked upon rebuilding my Volvo MD7A. Indeed, I would not have done so without some assistance, and that was forthcoming in the form of my friend, Alan Crouch a professional engineer. Our preliminary investigation involved taking off the head and the grim picture inside told even my untrained eye, that it was a mess, and would require some serious work to put right. The back cylinder was full of water.

Before accepting Alans offer of assistance I did make enquiries as to the cost of a new engine or professional rebuild. A new Volvo 2020 was some 6,500 and that includes your discount, said the cheerful man from Volspec. The man from French Marine quoted similar prices for the Yanmar so unless I sold Jan into slavery, a rebuild was the only option. Marinepower at Wroxham advised me that they had just completed the same job on the same engine and that came out at 3,500.

Alan was mortified at these prices and convinced me that we could do it. So, having made him promise that I would do the work and that he would be the advisor, I made arrangements to have the engine disconnected from the sail drive leg by Paul King and craned out. Not an easy job when it is p.. ing down with rain and everybody is getting very wet. The engine did fit neatly in the boot of my car so from Bradwell I drove to Ware to Alans work shop. Upon arriving I realised the first problem. Id

had a big crane at Bradwell and Alan did not: how were we going to get the engine out of the boot onto the floor? Well, with a few large pieces of wood and a hydraulic jack of course. Chock it up until it is level and then pull it across and lower to the ground. Easy! The engine remained in Alans workshop covered over and protected until after Christmas. The work took place over four consecutive Saturdays. The first stage was to dismantle the whole thing to find out how far the damage had gone. We discovered in the head that there was a flaw in the casting which for years had probably been held by the head gasket. When this went, it allowed water from the waterway into the back cylinder. Due to the water which had got into the engine emulsified oil was much in evidence. The head was in good condition otherwise.

The remainder of the fuel system was taken off and stored in a box. The fuel injection pump and injectors were taken to Wade Diesels in Ware who for 225 rebuilt the pump and reset the injectors. A marine diesel agent would have charged you an arm, someone else would have the leg later. Oh, and I forgot to mention how you get the fly wheel off. On an MD7A it is a real brute. Alan rigged up this machine which simply pulled it off. Without this professional equipment the job would not have been possible.

The timing case was next and this revealed all was well, and finally the sump. The sump filter required a new feed pipe, otherwise all OK. We could now get to the pistons which were duly removed. As we had suspected the rings were gone, either broken or heavily clogged and stuck or both. But thankfully the bore looked in good shape and the journals were declared perfect by Alan.

Anyone faced with the prospect of new piston rings beware. From a Volvo agent, even cut price, like Keyparts at Watford, you are still going to pay a lot of money. (This is the leg part I was referring to earlier). However do not despair readers because there is a company in Tottenham who did for me what I consider to be the deal of a lifetime. The head had to be welded and skimmed, the bore de- glazed and the pistons cleaned and the rings re- placed. I had already priced an exchange head at500 and 80 per piston for a set of rings. When I was quoted 75 to repair the head and the final bill came to 150 I was somewhat amazed. The secret is the price of the rings

you see they are Nissan rings and from a Nissan dealer they are 20. When you check the size and make, mate, you find they are made by Nissan, said the man, I ex- pect you pay a lot more than that for those parts in a Volvo box eh? I declined to say anything as the smile on my face prevented any further comment on my part. We could now commence the rebuild having re- paired or replaced everything that was wrong. At this point you do have to buy some Volvo parts which you cannot do without, gaskets. Lots of them. 3 sets in fact. Top, middle and bottom, as Bruce says, and they are not cheap when you consider that they are nothing more than bits of paper. And whats even more galling you dont use them all. You must also have (steal or obtain) a work- shop manual, Volspec supplied mine, it was a photocopy and was priced the same as a proper book. No comment! If you can imagine a surgeons operating table then this is what Alan made me use. It was clean and needed to be as you have to be scrupulously clean at this point. Everything was cleaned twice before assembly. The first task was to replace the pistons complete with new rings. I learnt a trick here, a cylindrical device which holds the rings in tight to the piston to enable insertion into the pot. The sump and filter were replaced and the block sat upright. During this time I had also taken the opportunity to paint everything in Volvo green, obtainable from your friendly agent 19.95. Not bad really as it does give your efforts a new appearance. (Unfortunately the tin lid does not fit back very readily and I have since painted a few other things green, including the floor of my dinghy when the tin overturned.) Fuel injector pump next but dont forget those timing marks, so important if you want the thing to start when youve finished. The manual gives good illustrations so even an idiot, and that includes me, can set it up correctly. We were on the home straight now, just the water pump, injectors, primary fuel filter and lifting pump to fit. A new diaphragm was needed for the lifting pump. Dont ask how much, you dont want to know what a small piece of rubber costs. This was subsequently dismantled once the engine was back in the boat as the two halves of the casing had become distorted. Fuel was easy to detect

running out. Alan decided that the solution was to grind the edges flat on a sheet of glass using grinding paste.The last bits to be fitted were the fuel filters, do not be confused by their size, long or short it is the end that screws on to the body which is important. I was convinced I had been supplied with the wrong ones and gave the man at Keyparts a hard time. I was still convinced I was right until I offered them up. It would appear that Volvos are shorter than other makes. Gleaming from its new coat of paint the engine was craned back into the boat, in the meantime Paul King had checked the saildrive leg and refitted it complete with a new doughnut (no, this is not something that is supplied by the local baker but another Volvo part which seals the saildrive leg). Again, please do not ask the price of this piece of rubber, it is just unbelievable. It was bolted back together and the moment of truth arrived, would it start? The answer was no. The more technically minded will immediately spot the deliberate mistake. Yes I had fuel. Yes I had bled the system. Yes everything was connected. Unfortunately there was no electricity in the batteries - they were flat. In all my enthusiasm I had forgotten all about them and assumed that they would maintain their charge over the winter no matter what. Stupid boy! New batteries in place she started, albeit reluctantly at first and with the aid of some jungle juice. Once in the water I could try for real. We were craned back into the water in April and things were not much better, she was still a very reluctant starter. I was a little disappointed to say the least. It then occurred to me that the travel of the cold start lever was not the same distance as previously. I checked the travel distance and found that this didnt seem to make any difference. Gerry Askham arrived and manned the injector pump and bang off she went first time. It proved to be the cold start lever. The travel needed to be slackened off so that it could pull at 90 degrees rather than in line. It was reassuring that my instincts were correct. I just lacked the courage, or technical knowledge or both, to carry it through. The engine now runs like a sewing machine and justifies the money spent. The effort was well worthwhile. The cost was 1,400

which was a substantial saving. The other benefits were considerable job satisfaction and knowing everything about my engine. My thanks to Alan Crouch for his technical and spiritual guidance and not least for the loan of his workshop and professional knowledge. He taught me the virtue of

patience and of being methodical.Gerry Askham for his inspired appearance at the right moment and to Paul King for having the least glamorous, but by no means unimportant, part.

John Pepper