Drives won't trim in
 

Hey guys. I was trying a search on this, but couldn't come up with the exact issue. Both drives (was just one, but as of this season the port is starting with this issue) will trim out,but to trim in I need to use the force of the prop right before I come off plane to get the drives to trim back in. I was going to replace or rebuild the rams as they do not sag or shift while underway. Is there anything else I should check first or does this seem to be the trim cylinders seizing up? Since I'm going to be trailering again and not on a lift, I will need to make sure I will be able to get the drives in the water.

Is the trim pump making noise when you try to trim in.
If it is then check the lines on the cylinders.To see if they are broken or leaking.
If not then check to make sure the power is getting to the pump when the button is pressed and that you have a good ground.

The pumps are working. When I push the buttons they fire up and sound fine. I'm thinking it's just the cylinders. They have some years on them. I did not see any leaks and there is plenty of fluid still.

I would replace the trim lines from the cylinders to gimble area.Then bleed them and try it.
you have nothing to lose since you should replace them periodically anyways.And 90 percent of the time its them.

DO they have some how to's on how to bleed those lines? It will be my first go at this.

Have you ever checked the filter screens in the pumps to see if something is going bad. Also lines could be sucking air if loose. a hydraulic line can suck air and not leak fluid. are your pumps mounted level or on a angle as in transom or firewall.

I haven't checked the filter screens, but will definitely do that too. The pumps are on the firewall. The starboard has been doing this for 2 seasons. The port started this season and has not caught up to the starboard as far as how bad it is.

Try adding some oil

Pumps are full. I check the fluid levels consistently.

Oil level is why I asked how level the pumps are mounted. Either way if they are tilted forward or back you could be sucking air into the line while running in choppy waters. I have to run mine over full with puketanks even though they are level just to keep from sucking air. Mainly on my tab pumps I'm always adjusting. And I run really thin oil in them to speed reaction time up

If you have kept the reservoirs full and the cylinders have raised and lowered then it is bled. It self bleeds as the fluid passes through the reservoir when going up and down. As long as you have kept them full there is no way you can get air in the system through the reservoir.

What drives are these on? What pumps are these? White plastic reservoirs?? Round metal reservoirs?? Square metal pumps??

I had a similar issue this spring. Replaced the Trim Sending Units and was good to go

They look level and mounted to the firewall.

Bravo 1. White plastic res. Original pumps that were on the boat. so very old to say the least.

I'll add this to my troubleshooting as well.


Thanks everyone that's been able to help so far.

Sounds like the trim cylinders are sticky. I would rebuild them and that should take care of your issue. I’ve had it happen where you had to stand on the drive to get it to go down.

That is my situation. Either that or using the force of the prop right as you come off plane.

There is a shuttle valve in the pumps. Make sure they are not hanging up.

Sorry wrong thread i posted

the trim cyl has a LOT of power to raise the drive. has very little to lower the drive. there is a seal in the middle stops fluid from pressurizing both sides of the piston. if they aren't too corroded up, rebuild is cheap and easy.

For what it's worth, I experienced the same thing, after weeks of chasing, I replaced the trim cylinders and it solved my problem. SSM drives but same idea/issue.

I'm probably going to look into rebuild kits regardless. These are fairly old so it was my first though that the cylinders were taking a crap.