Run it for a while with the valves adjusted, then check them again. Quite often, a neglected engine will have carbon built up on the valves, especially the intake, and it will prevent the valve closing properly. The clearance will disappear as the carbon works off, so the vavles will need to be set again.

Check the chain stretch -- if more than 8 degress on the cam, replace chain.

Check for leaks in the fuel system. The hoses go bad with age, and the result is air getting pulled into the suction side. This causes hard starts.

Bad glowplugs won't help, either. Check resistance (pull the plug off the relay and check that way -- 06-0.8 ohm each). Replace any bad ones. Glow plug lamp will blink after starting if you ahve a bad one, won't lite at all if more than two are gone.

DO NOT use ether or starting fluid, this is a good way to blow a head gasket or break the ring lands, precipitating a rebuild. The ether will ignite off the glow plugs long before the piston is in the correct rotational position.

For the heater servo, $400 is a good price. Get one from Performance Analysis, it has an aluminum body rather than plastic and won't crack. You're pretty much stuck with that price, they are expensive.

Peter