Trim ram question.

[chadmyrvik]

I'm in the process of replacing some leaking trim seals on a 2003 200vmax. My question is, when I removed the screw on cap there is fluid on top of the piston, is there supposed to be fluid on top or does that mean the seals on the piston are bad too?

[pstephens46]

Not sure what is meaned by top of piston.

Based on where the two hydraulic lines connect to the cylinder, you would have fluid on both sides. One pushes in one direction, turn the wheel in other direction, fluid is pushed the other way. There are check valves in the helm to allow fluid to move in or out of cylinder.

My understanding of system. Correct me if I am wrong.

Jesus Christ. I should delete this.

I was thinking Sea Star seals, never mind! Disregard!

My sea star seals need to be replaced......

[TownsendsFJR1300]

Not sure what is meaned by top of piston.

Based on where the two hydraulic lines connect to the cylinder, you would have fluid on both sides. One pushes in one direction, turn the wheel in other direction, fluid is pushed the other way. There are check valves in the helm to allow fluid to move in or out of cylinder.

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Plus 1 ^^^. You should be able to simply remove the caps, then the seals, and re-install. No reason to pull the ram..

[pstephens46]

Let me try again.....with trim/tilt in mind.

Rodbolt mentioned awhile back that Yamaha has used two types of units. Can't recall the terms he uses. One uses pressure on one side. (My F150) So oil on top of piston would seem to be an issue with this type. Another functions differently perhaps with pressure on both sides of piston, depending on which direction the unit is moving. Damned if I know which one the op has.

Now. Maybe someone can clarify which unit the op has.

[TownsendsFJR1300]

Op, can you post the complete MODEL # so we can check the parts fisch?

Possibly this one:

http://www.boats.net/parts/search/Ya...201/parts.html.

Trim caps do fail and leak(obviously).

If their working fine other than leaking, I'd think your fine.

Now, if the trim wasn't holding the engine up / operating properly, you'd likely have other issues (possibly those seals you mentioned)..





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[fairdeal]

Rodbolt was distinguishing between the trim ram being "pulled" down and being "pushed" down.

In either case, as the trim ram retracts, the space above it fills with fluid.

There is no "air space" anywhere, any time except in the top of the reservoir.

[pstephens46]

Rodbolt was distinguishing between the trim ram being "pulled" down and being "pushed" down.

In either case, as the trim ram retracts, the space above it fills with fluid.

There is no "air space" anywhere, any time except in the top of the reservoir.

That's it!

[TownsendsFJR1300]

An interesting read, especially the : Retraction force difference

References the "pull" factor..

https://en.wikipedia.org/wiki/Hydraulic_cylinder




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[rodbolt17]

***
someone does pay attention.

most v4 and 2.6Lv6 from about 2000 use a "showa" pump assy.
this can be identified by the plastic reservoir.
that system does NOT use pressure down.
if the dust seal on the cap leaks odds are high that a piston oring is bad or the cyl scuffed.

an easy way to ID the system?
look at the parts diagram.
if the cap uses an oring and a back up ring and a wiper seal it is a pressure down type system.
if all the cap uses is a wiper then it is NOT a pressure down system.

[chadmyrvik]

Year 2003, model is a vz200tlrb

[TownsendsFJR1300]

2003 VZ200TLRB Yamaha Outboard POWER TRIM TILT ASSY 1 Diagram and Parts

I think your question has already been answered up above...

[rodbolt17]

see.
memory was wrong.
that diagram shows a pressure down system.
but if the seal leaks I would still pull the rams,evacuate the fluid and inspect the bores.