Guess what! The suggestion here was to check the flywheel key and as a last resort I took off the flywheel after checking the key and had a look at the PCV valve. What a mess - Firstly there were 2 valves on top of one another, there was no proper gasket just some silicon crxp that had not been applied correctly and a bolt hole in the cover looked like it had worn out on one side. What's more the gauze had been replaced with some other wire mesh stuff.
Unfortunately, I didn't have another cover and gasket so I had to do much the same and I used a washer to cover the gap in the bolt hole in the cover. I only used one PCV valve.
Put it back together gave it some fuel and it started with my drill first time! It still has that extra loud sound to it though. Could that be because of high crankcase pressure and bad PCV chest seal?
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