new pcv valve + hose ... aged 27 years

i did get it a compression check about 11k miles ago
#s were decent enough, i suppose (for a cold engine (if it matters))

how often ought i seek to get compression test #s done onna schedule
You read wrong....most accurate readings will show when the engine is at room temp. You want to see every cylinder to fall within a max. of 15% of each other.
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Kind of a pita to remove spark plugs for a compression test on a hot engine, plus it's been said hot, or cold you don't get the same readings as at room temp. I've always taken a compression reading at room temp, even on my snowmobile, marine, and bike engines. Its nice to have base line to go by when these engines are fresh/new.
You need to take into account that these high mileage engines have carboned up piston tops that will read compression higher than they should be. It's why I like to hit them with sea foam before testing. Let the smoke show begin!
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i recall i read that there is limited time to pull the plugs and check compression after engine shutoff
time is of the essence... so this is where i must find the correct deets for education

FSM will show the deets if i can find the pages
Sounds bs to me. I never learned anything such. I was always taught room temp by a yamaha motorcycle service manager, and an engineer from mopar in mich.
No real + genuine noticeable changes in mpg miles per tank with this new pcv
1700 taco miles on this new pcv so far
I recall before changing it wiping cleaning oily dirty around it on the VC surface
It is still clean of the oily
So perhaps the old one was not working efficiently and weeping some oil vapour from around the grommet between pcv valve
IDK :confused:
Suppose I shall keep a monitor onit and see how it goes