Hi
Have an old 5FDF25
Always been perfect
Suddenly it started to drop slowly
Now it lift but won't Rev fully
It has a pyroban system. I have loosened all off as thought might not be getting enough air
But still only revs at most half way
I have changed fuel filter
If you try to Rev quick it bogs down then cuts out
It was perfect but I think someone messed with pyroban lever
But as I have basically loosened this fully so should be getting loads of air I can't see that is problem
Tia