70 bet trim not working

[Ian47 leebrek]

I have changed the motor on the trim unit, now when I attempt to raise it the motor runs but it doesn't move. I can manually lift it to the raised position with the bypass closed, but it doesn't hold. If I turn the bypass anticlockwise the trim rams slowly extend but not the raise ram. If I turn the bypass clockwise it doesn't move. I have topped it up until it's full of oil. Can it get an airlock some where?

[TownsendsFJR1300]

See if this video helps... What was the original problem?

https://www.youtube.com/watch?v=nfPyXNQQOf4S

[99yam40]

if you can raise manually with bypass closed then there is not enough fluid in there or something is leaking by
my wild ass guess is not enough fluid

[Ian47 leebrek]

The original problem was that I was removing a damaged autolube power head and fitting an older mix power head. While I was rebuilding it I decided to use the older motor as it was in better condition. Both trim units were working fine previously. The older motor turned out to have a larger spigot on the base plate so I machined it down to fit. While the motor was off I up turned the unit to drain the rest of the oil out. It did work initially for a few times then stopped. The fact that it pumps with the bypass open leads me to think that the motor is correctly aligned, it seems more like an air problem.

[Ian47 leebrek]

Excellent video, I think I have been misunderstanding the manual release valve, I thought it was a needle valve where it had to be fully closed clockwise to operate the power trim, but in fact it has to be fully anticlockwise to operate. After you operate it several times you forget what the original position was! Thank you for your advice.

[TownsendsFJR1300]

Your welcome for the video.

Well that clears up a bunch, there's apparently air still in the unit.

When re-assembling the unit from a rebuild, its usually filled with fluid as you go along in the assembly. Hopefully you can bleed as in the video and get it working correctly.

Please post back how it goes..