Tight MVVVs 1.5 cc

[Fourfingers]

Another day, another problem ....
Any help with the following most welcome:
Just got a 1.5 MVVS diesel circa 1990 vintage.  Probably a collector - ran a bit then in the case for the duration.
This is the problem: unbelievably tight at TDC, so that its virtually imposssible to flick and feels like when forced over somethings going to break!
No, its not gummed up ... had it in bits and its super clean.  Tried the Brasso, Silvo treatment, and even smoker's toothpaste.  The contrapiston now moves under protest, but no amount of force will get the piston up the liner using a dowel and sledgehammer.....
I'm guessing I need to abrade the piston or liner - but how?  I'm no engineer and only have farm-yard tools.
Final thought: there's no gasket or seal below the cylinder liner.  Maybe there should be?
Looking fwd to your valued contributions.
Many thanks.
4f

[OZPAF]

Will it turn over with head removed? It sounds as though it has very little head clearance or possibly none.
I think I would investigate that before relieving the top of the piston.
I would advise you to post this problem on the Barkston Control Line site.

John

[Fourfingers]

thanks John
was actually overnight piston at TDC.  got it lapped and now running sweet.   still going well after being buried!
4f

[OZPAF]

Good to hear your problems solved.
john

[Fourfingers]

Here are today's corrections and clarifications ....
For 'overnight', read 'overtight'.
Thank you!
4f