Trim pump noise

[Gary H NC]

Is it normal for the trim pump to be much louder going down than it is going up?
Could a relay cause this? I have already replaced pump and motor.Had the drive off,everything is greased.
I have bled the system per OMC manual.
Anyone got an idea what else to check?

 

[Don S]

Re: Trim pump noise

Yes it's normal. One direction it's lifting the weight, the other way has gravity helping. Plus one direction of the pumps is a higher pressure than the other.

 

[Gary H NC]

Re: Trim pump noise

Thankyou Don,
I guess going down would be the low pressure side.
I just don't remember it being as loud when i first bought the boat.
The new pump makes a little less noise.At least now i have a spare pump and motor.
Bleeding it, the book says to run it up and down 8 to 10 times with the fill plug out,then top off the fluid and install plug.No need to bleed the lines?