Trim will go up but will not go down.

[Woody70]

Trim will go up but will not go down.
When I try to trim down the motor just whines like there is no load on it.
I noticed there's two blue wires that are disconnected and I don't know if that has anything to do with it or not.

I got this boat from my dad after he passed away it has been sitting in the driveway for about eight years now.
Any help you guys could give me would be greatly appreciated.
Thank you

120 hp I/O
MC-1 outdrive

 

[alldodge]

Re: Trim will go up but will not go down.

The two wires come from the shift interupter and have no effect on trim. They will be needed or the interupter circuit fixed prior to use.

When the drive goes up and then stops does the sound change for the pump; Kind of like a higher pitch squeal? I hope the answer is yes, and if yes when the down button is pressed does the motor make the same type squeal but doesn't move or just the lower tone noise? If the motor squeals in both directions your pump is working but something is stuck. If there is two different sounds then it could be you have a internal hydraulic leak or the valves are stuck.

 

[Don S]

Re: Trim will go up but will not go down.

That is not a shift interrupt switch, it's the reverse lock switch that keeps the pump from being operated when in reverse.

Was your control in reverse when you was trying to trim down? You really need to get that switch hooked back up

What year is your engine and drive? SN? Early 70's boat?

 

[Woody70]

Re: Trim will go up but will not go down.

Yes it's an older 70s boat.
Outdrive serial number is 3440864
Engine serial number is 2362287.

I had the controls in neutral when I was testing it

When you trim up you can tell there's a load on it but when you trim down the motor just whines

Hear is a video so you can hear what it sounds like

Trim pump - YouTube

Thanks
Woody

 

[alldodge]

Re: Trim will go up but will not go down.

Sounds like your going to need a new pump but suggest you rebuild the trim cylinders first. It doesn't cost that much in comparrison to the pump and if you need the pump at least you know your cylinders are OK

 

[Woody70]

Re: Trim will go up but will not go down.

Thanks for the help guys.
Turns out the pump was fine somebody used a tapered pipe fitting instead of a compression fitting on the bottom of the pump.
I didn't see that most of the hydraulic fluid had ran out of it down into the bilge.
I had to take the bottom of the pump off drill and tap new threads to stop it from leaking.