So you're saying the pump is running but the out drive is not moving. And
you are certain you are going down. Then it is probably the pump. You
don't say what year. Way back merc had one line to each cylinder. Now they
have two. You can loosen the lines at the distribution block under the
drive and see if the drive lowers. It will make a mess and the drive will
go down fast so be ready. A strong guy can hold up a drive but expect it to
be heavy or you will be surprised. That will eliminate that the drive is
hung or binding. You can also tell by the pump noise if the pump is
straining or not. The pump is a reversible hydralic pump.

"Jodon2" wrote in message
...
Just bought a 21' Renken with a 3.7 Merc I/O. Problem is that the outdrive
tilt
raised but now won't lower. Fluid is ok, tilt motor runs but won't engage
to
lower unit. About a week ago unit worked fine. Thanks.
Joe