Paulb1
New Member
I’m having trouble with some Bennett trim tabs, strarboard side works fine but the port side sounds likes it’s working but there’s no movement on the trim tab! Any ideas?
Bennett trim tab problems
- Thread starter Paulb1
- Start date
superheat6k
Well-Known Member
Possibly a burnt out solenoid or poor connection to the port solenoid. The solenoid directs the flow from the pump to the selected tab. Be aware that on most installations the port tab is operated by the stbd switch.
Paulb1
New Member
Thanks for the information, I’ll have a look over the weekend. ?
superheat6k
Well-Known Member
Mine are not Bennett, but I expect the principle is similar. There are three feeds in to the pump unit and one negative return.
One for each solenoid and the third for the pump.
When going down the pump and the selected solenoid operate, when going back up just the solenoid operates, the return being caused by the large spring inside the rams. So when selecting the up position the solenoid should be audible as it clicks in and out.
No click would bear out my suggestion of a duff or non energising solenoid.
There is a small shuttle valve that operates when the pump runs to force the hydraulic pressure into the Rams selected.
One for each solenoid and the third for the pump.
When going down the pump and the selected solenoid operate, when going back up just the solenoid operates, the return being caused by the large spring inside the rams. So when selecting the up position the solenoid should be audible as it clicks in and out.
No click would bear out my suggestion of a duff or non energising solenoid.
There is a small shuttle valve that operates when the pump runs to force the hydraulic pressure into the Rams selected.
Plum
Well-Known Member
This document, which includes a troubleshooting guide, may help you Bennett trimtab info & troubleshooting.pdf
Www.solocoastalsailing.co.uk
Paulb1
New Member
All sorted, thank you
Paulb1
New Member
All sorted thanks; it was a failed solenoid.
salar
Well-Known Member
Lucky it was only that! On mine the ram seal failed, sucked water into the oil which screwed the indicator and pump. A £1 oil seal failed costing me over £400 in parts alone! If the oil ever looks milky, sort it out immediately before the pump fails.
