Bob Birkett and Mary turned up one Saturday morning to spend the day working on getting my “7” back on the road. At least I had purchased a new battery in preparation and Bob proceeded to get to work on the assumption “If it was driven into the garage there can’t be too much amiss.” Spinning the engine showed no spark at the plugs and on taking the distributor cap off we noticed an unusual amount of corrosion which was cleaned up to no avail. A rummage through the garage uncovered a new set of points and a condenser which were soon fitted, but still no spark at the points. The coil was checked and changed, the points removed, refitted and reset and at last a spark. The cap was put back on, engine turned but no spark at any of the plugs, so the rotor arm was changed and finally the plugs were sparking. The next problem was no fuel so, in order to short cut the system, we simply took the top off of the carburettor bowl (SU) and filled it with petrol but again the engine refused to fire. Bob then proceeded to remove the dashpot cover looking for some other clues as to the reasons for our lack of success. I was busy with something else when I heard Bob saying “OK what have you done with the spring?” Although it had been sometime since I’d worked on the car I couldn’t remember removing the spring, although I vaguely remembered fitting a blue spring to another vehicle and was almost certain that it had been bought at Beaulieu and not simply transferred. Bob related some of this tale to Ian Mason Smith who offered to look through his spares and see if he could find an appropriate spring and, at the following club night he produced a red spring which he reckoned would at least get the engine running. The spring was duly fitted but still no luck. The battery was a further cause for concern, although charged the acid had no bubbles, so that was returned and replaced. Bob had by this time “the bit between his teeth” and was determined to persevere with the challenge but it was going to be about four weeks before there was a convenient slot in our respective calendars, and in the interim I was equally determined to sort it out before he arrived I visited Burlen Services at Salisbury who, as usual, were extremely helpful and to cut the process of elimination short it transpires that not all SU’s had springs! Some early examples had “weighted pistons” thus obviating the need for a spring. Back at the car by a process of elimination I figured that there was insufficient suction to get the fuel from the carburettor bowl into the engine and after pouring some Redex down the bores over a few days in the hope of raising the compression I was resigned to the fact that the job was rather greater than anticipated and I contacted Bob to voice my fears. Bob and Mary duly arrived, in the MGB, complete with a distributor, carburettor (Zenith) as original, fuel pump, coil and compression gauge amongst various other bits and pieces and confirmed no compression on cylinder numbers 2 & 3. Copious amounts of even more Redex were introduced through the plug holes in the hope of loosening the rings but no change, so maybe it was valve related? With the valve cover removed it was easy to see that the exhaust valves of both these cylinders were stuck open. We tried, for some time, to free them without success using even more Redex, and Lusol but, eventually Bob decided the only solution was to remove the head which, to put it mildly, was a bit reluctant to move. Finally it was off and by a process of gentle taps on the valve heads whilst turning the engine the valves were operating as required. At the same time the head and pistons were cleaned Luckily I had a spare gasket so the head was refitted and, as the fuel pump had been making the right noises, we put some fuel into the tank, drained it, then added more. The SU had been stripped and rebuilt without any spring and after a few turns we were rewarded with a polite cough and then success the engine was firing on all four albeit with clouds of smoke. In fact the smoke was so great that I couldn’t see anything behind me but eventually that cleared. I was all for going ahead and doing the valves but Bob suggested just running it, which is what I have been doing , up and down the drive, I can even get into 3rd gear, relearning the black art of double declutching, and everything is gradually loosening up. Next thing is to try and arrange one of these half price MOT’s !!!

Gordon Cowie DA7C