MB 617 injection pump mystery

[rocket88]

I installed a used recent rebuild 617 turbo with 4 speed manual into an '84 300TDT.
This engine sat not running for 1.5 years minimum prior to this.

This engine smokes (blue) too much with warm compression readings of:
1- 400
2- 400
3- 420 (fuel ignited during this test)
4- 390
5- 380
this supports recent rebuild story of seller .... at least rings.
can compression rings be good but oil rings be stuck??

Also does not idle while stone cold without foot on accelerator until it begins to warm up, then searches, when fully warm idles normally

This engine when revved up rpm does not drop to idle normally with release of accelerator, rpms "float" down to normal idle very slowly while stationary in neutral. From 2500 takes maybe 6 or 7 seconds to drop to 1000.

While cruising in gear its even worse, momentum of vehicle seems to sustain rpm even more, making the usual use of compression to slow vehicle impossible possibly dangerous.

Adjust governor damper out half a turn does not help ...
Adjust governor damper in half a turn initiates loping, worsens searching.

Assuming something is stuck or sticky in IP, (per comment of Oregon Fuel Injection guy) are there any oil additives that may "unstuck" it.... ? (Why would he tell me)

Gus at Pacific says "gee I don't know what could cause that" .... Poll: who believes that? He seems like a nice man, however he is a Swiss guy who has spent his life working on these IP pumps.....

Am I getting cynical?

Thanks in advance.