Dont know if this will help ,I had an issue where hose to decompressor was not sealing.
Therefore no vacuum whem running.
Valve would not close when running.
So no compression.
I cut the ends from hose, heat with a lighter and refit.
It will always start when you prime it though.
This seams to fit your symptoms.
Let me know what you think.

Last edited by mark electric; 26/08/12 06:53 AM. Reason: spelling as usual

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