TM 5-3805-280-24-1
Too low penetration rate (cont'd)
Fully loosen V3 drifter power
regulator setting.
While drilling in manual mode,
check R2 pressure.
yes
R2 pressure higher than normal?
no
yes
R2 pressure lower than normal?
Loosen V2 setting screw to
Tighten V2 setting screw to reduce
increase R2 pressure.
R2 pressure.
yes
yes
Re-adjust R2
R2 pressure increases?
R2 pressure reduces?
pressure
no
no
V2 sppol is jammed.
Check LP pressure is lower than
Check maximum pressure limiter
15 bar.
MP for leak.
V2 spool is jammed.
Note R2 pressure obtained while
drilling in manual mode.
Compare R2 pressure obtained
while drilling in automatic
mode with its value while dril
l
ing in manual mode.
yes
R2 auto" = R2 manual" ?
no
Loosen V2 setting until
R2 auto" = R2 manual".
Re- set V3 drifter
power regulator.
10-26
