Yamaha trim cylinder seal leaking

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nevsatII

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My trim cylinder seal is leaking on my F250. Is this a do-it-yourself repair or should I leave it to a professional ? Has anyone changed these before that could share some info?
Thanks Jim
 
If it's the main cylinder, then it's a big job (that as to be removed by completely disassembling the main cylinder to it's base so the new seal can go on from the bottom). If it's the two smaller ones on he sides that aren't connected at the top, it's a simple fix. All of this is as I was told from a yamaha tech on the same issue.
 
It's the small cylinder on the port side. It looks like you have to unscrew the top of the cylinder off with a spanner wrench, change the seal and replace. What I'm worried about is all the fluid going to be lost.
 
It is not a big deal, you can buy the tool from SIM and the parts you need. I bought new seal holders. You put motor all the way up and lock in place, change seals and refill and bleed. If you need to, pickup a factory manual from SIM. But as stated by Salinity it is pretty easy. The refill nut is on the left and the bleed screw is on the right. You want to run the motor up and down about 5 times, then check fluid level again. Careful when you take motor off the travel holder,make sure rams have some pressure. Just changing seal doesn't lose much fluid, if you don't pull the rams and pistons out. If seal holder is stuck,I used a drift punch to turn it, One of the reasons for ordering new seal holders. Do both while you are at it.
 
nevsatII said:
It's the small cylinder on the port side. It looks like you have to unscrew the top of the cylinder off with a spanner wrench, change the seal and replace. What I'm worried about is all the fluid going to be lost.
Click to expand...

A few things to keep in mind:
First of all, make sure the motor is locked on the stops to prevent it from falling down.
The seal covers on the cylinder may or may not come off easily or undamaged. Sometimes the spanner doesn't do it. (The Yami tool is expensive, cheaper ones ,Harbor Freight, will do but make sure you get the correct pin spacing) It is common to have to whack it with a punch or 'chisel' to free it up. I would plan on have a new cap on hand as well as the seals. Take a good look at the piston rod beforehand to make sure it is not corroded. If it is, you may need to replace the rod.
If you have the time, diassemble and inspect before buying parts so that you get only and all the parts needed.
Don't worry about he fluid. My advice is to drain out as much of the old as you can and fill up with fresh. This is done to eliminate any water that might have gotten into the fluid. Water will corrode the internals.
Of course, you will need to bleed the system but that is relatively easy. Cycle the rods a few times, check fluid and add as needed. Repeat that process several times. Do not stand under the motor and keep your fingers away from pinch points. The motor could drop unexpectedly as the air is flushed out.
Good luck
 
Thanks for all the help, I'm going to give it a try once I get the parts together.

GulfGrady I keep the boat on a lift and trailer once in a while depending where I want to fish.
 
My 2004 f225's are also leaking on the trim cylinders, i ordered the tool from my local yamaha dealer & bought the caps & seals. I will let you know next week when i work on them. I had one seal repalaced last year & the remaining 3 are leaking now, I heard yamaha changed the design on the seals not for the better causing leaks after a few years..
 
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