RE5 Water pump leak

[Mick Taylor]

Hi, my RE5A has a coolant leak (when it is left standing) from the telltale hole on the pump cover. There is no sign of oil, just coolant; and no sign of coolant in the engine oil. The book suggests removing the large transmission cover to get at the inner side of the impeller shaft to replace both the oil seal and the water seal. I would much rather remove just the small water pump cover and replace the water seal because it is clearly much less grief; but is that possible? has anyone on the forum successfully replaced the water pump seal without removing the main transmission cover and if so, did it work and are there any pitfalls uch as getting the old seal out with the impeller shaft in situ, or should I just get on with removing the large cover?. Any advice from those who know would be much appreciated.On another note has anyone devised a method of working out whether the infamous RE5 flat spot is caused by the port valve opening too soon or too late in relation to the secondary throttle; is there a difference in the nature of the flat spot, hesitation, stuttering, misfire, power loss etc etc due to the opening of the port valve being pemature or retarded.? (does that make sense?)Mick.