Seal replacement tilt/ trim 88-70 hp 2stroke

[Allen]

My 88 oil injected Yamaha outboard is leaking hydraulic fluid on the two trim cylinders and my local yamaha shop ordered the wiper seals and o-rings, but is not ready to swap the soft parts as they just took on yamaha outboards as a sideline to their motorcycle shop.

After looking at the parts list here I may need more o-rings than I ordered. I ordered the top two orings and the external lip ( wiper) seal, but I suspect the o-rings down at the big cylinder that the ram rod connects to should also be replaced. Anyone done this agree that all of those o-rings probably need replacement? I can't tell where the pressure side of the system is, but suspect it is below part # 56 ( assembly #).

I can get a spanner wrench to remove the top of the rams, but I believe with the engine up ( rams extended) that from his computer file the spring inside will be collapsed and ready to launch the cap once it unthreads. I imagine I need to lower the rams so I can re-assemble it.

Anyone know the procedure for doing the seal replacement?

Thanks

Allen

[Ken]

Allen,
I've never done it - but the procedure is in the Yamaha shop manual - I recommend that you get it to guide you along. I would also replace every seal, gasket, and o-ring in that sucker while you have it torn down.
Good luck [img]smile.gif[/img] ,
Ken K

[Terry]

Once upon a time, the folks at boats.net gave me a part number for a seal "kit" for my trim/tilt pump. I've since lost it and I never did the rebuild, but you may want to look into the rebuild kit vs. buying seals one-by-one.

[Dennisg]

Allen, I never did the seal replacement, but I would like to bring to your attention a similar problem i had. I was leaking hyd. oil from the ram seals, when I went for the seals, the service tech told me that the seals very rarely go for no reason. It turned out the alum. that held the seals was corroded(no doubt electrolsis) and I had to replace the entire trim/tilt unit. So before you go nuts with the seals, look for any sigh on corrosion.You will save a lot in the long run by replacing the entire unit. Plus you will be good for another 10 years or so.
Dennis