I think the trim pump is shot on our 89' 115HP Merc O/B. Is it a big job to replace this?

Don't get all over me about this not being an "offshore" question. It's my wife's boat and no trim = no trim.

That would be a 4 cyl Farce version of a Merc, right?? Need to know more specifics on the problem to be of any real help, but I do have all the books on them. A reliable Merc Tech. would be the way to go but be aware that there can be some real simple things wrong and you can pay BIG bucks for more fix than you really need. Give me a ser.# and I can help you more if you want. --- [email protected]

Trim motor can be rebuilt cheaply if the motor is bad. Solenoids are reasonably inexpensive. A complete o-ring and check-valve kit is inexpensive as well.

Get some estimates and if unreasonable, get a service manual and get the parts and go for it.

Thanks for your replies. The serial # is OC189509. It's a Mercury, not a Farce. There is no sound from the trim motor at all, so I tried a fully charged battery. Engine runs fine and all other electricals are working as normal. There is power at the trim switch, and each solenoid on engine clicks when switch is pressed up or down. I overroad the trim switch at the control box and still only hear solenoids click. Next, jumped the solenoids and still nothing in either direction. Checked all visible wire connections between switch/solenoids/pump and everything looks fine. Is there a fuse in here somewhere? I only found one fuse, it checked out OK but didn't seem related to the trim.
Next I better find a manual.

I think that you have done all the right checks and that the pump motor is either fried or has a hung brush. Check out the simple stuff first and proceed from there. --- Jer