Offshoreonly.com - Drives won't trim in

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Quote:

Originally Posted by sleev-les (Post 4597839)

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

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

Quote:

Originally Posted by class6 (Post 4597908)

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

They look level and mounted to the firewall.

Quote:

Originally Posted by picklenjim (Post 4598031)

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

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

Quote:

Originally Posted by mysweetone (Post 4598050)

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

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.

Quote:

Originally Posted by mickeymcclgn (Post 4598431)

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.