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Compression diagnosis 1200 herald


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Hi All

having just collected my new herald 1200 I have worked my way round a poor starting problem. Amongst the usual adjustments (inc valve clearances that were all too tight)  a new hi torque starter motor as helped enormously. However compression test cold ( can't run up to temp until new thermostat cover arrives) revealed some interesting and low results as follows 

1= 110 psi

2= 70 psi

3= 55 psi

4=90 psi

other than a very tired engine, does this likely mean a gasket fail between 2 and 3? 

Before leaping into a full rebuild, would a head off visual inspection for scoring,  relap of valves, skim and new gasket be a logical first step .... or am I simply putting off the inevitable? 

Your thoughts greatly appreciated ?


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