prv
Well-known member
So here's an idea. Change the oil and go out and thrash the pants off it for at least four hours. If it doesn't blow up then it's good for a good few more years. If it does then the decision has been made!
Thrashing it at max revs, throttle on the stop, for half an hour will probably improve it. I used to do that annually on Kindred Spirit's 2GM20 and it ran better afterwards. Burns out the carbon in the exhaust valves, manifold, and elbow.
The 2GM20 is only rated for one hour at absolute max; there's a lower "max continuous" speed to use for the rest of your suggested thrash about. But yeah, at the end of it the owner should be more confident, the engine raring to go, and the shiny one less of a temptation
Pete