Faac 640 query

[Pablox]

I moved my query from the introduction section, see is there any more action in the Faac section. 

I  recently stripped down an old Faac 640 automatic barrier, rebuilt it including a brand new piston and a new spring for a 7 metre beam.

Electrically it works perfectly but it groans and is very noisy. When closing I have to assist it, by leaning on it.
Note: As it's inside my garage, I only have a 2 metre plank instead of a 7 metre beam installed.


Used genuine Faac oil and level on dipstick is OK.
Bled pistons for air a number of times, spring side when opening, non spring side when closing. (made no difference)
When I put pump in manual operation, the motor runs quietly, and the barrier rises quietly by hand.

My question is when closing against the 7 metre spring does the barrier need the assistance of the 7 metre beam or should the pump overcome the resistance regardless.
Why is it noisy and groaning, I don't recall it being so, when it was last used (long time ago). Is the pump ill ?

Thanks.

[Pablox]

This forum has the quietest 1740 members on the internet.