Commander 3000 upgrade to mercury 4000 control box help

[Eric123]

So my old control box was a commander 3000 and it had 3 wires on the tilt/trim. Now i upgraded to a mercury 4000 gen 2 and the tilt/trim has 4 wires. 1 which i think goes to the trailer assist, but my boat didn't have that. So what do i do with the wire? Do i connect it to the up wire, cause on my switch the up trim and trailer assist is on the same up function of the button. Or do i leave in unattached?

I have left it unattached, but now i noticed that when i am driving forward and try to trim up on the motor it will not go up. But when i am stopped or on the trailer it will go up. I can put it up on the trailer and stand on the lower half of the enging and it will hold my weight with out leaking down.. So what could be causing it to go down when driving in the water? If i go slow it will trim up, but at half to full throttle it will not go up...

Any help please, And thanks. Could it be the wire i left off or do i have a new problem.

 

[alldodge]

This is the wiring with a trailer button



For all around wiring, I would connect the Purple/White with the Blue/White. Doing this bypasses the trailer switch and is no longer needed, but will still work.

So far as the not working when moving, this is another issue and need to know which wires were connected to what/where

 

[Eric123]

ok, thanks. I went outside while i was waiting on a response and changed the trim switch in the handle with the switch out of my old handle. I will test it out tomorrow (if i get a chance) and see if that new switch wiring was my problem or if i have a totally new problem all together. Thanks for the reply

 

[Eric123]

Just got back from testing. And i still have a issue with the trim not holding. Here is what i know:

When boat on trailer:
1. The up and down function works fine on all 3 locations of the boat.
2. The motor will hold up without leaking down for 1 day so far.
3. The motor will lift up with me and my son standing on the lower unit fin, roughly 400lbs.
4. I can't reproduce the motor going down on the trailer.

When in water:
1. While in water sitting still, the up and down works fine.
2. While in water sitting still, the motor will hold up without leaking down.

When in water driving:
1. When i am going slow the motor will trim up and down.
2. When i am going almost at breaking a wake, the motor will not trim up.
3. When getting on plane, motor will not trim up. If i trim it up from a stop then try and get on plane, it will go down.
4. If i trim motor up from a stop and "punch" the throttle it will go down.

When driving on plane:
1 When i am on plane, i can see the trim go up and usually it will hold.
2. Down works fine on plane.

I don't have any issues with the down part. It is my up side that doesn't move or hold under pressure of acceleration.
Is there any orings i need to check the the valve body? If so can someone tell me where and what to check. My boat and motor is a 1999 Bass Tracker with a 90hp Mercury outboard, same year as boat. Thanks

 

[alldodge]

If this was a mercruiser I would say need probably rebuild the valve body. Being an OB it would probably be the same, both are hydraulic. It probably heats up and starts leaking more. Could ask in the OB section to see what those guys say

 

[Eric123]

Thanks for helping. And yeah, i will repost this, i kinda got off topic here.