Yamaha 70 tilt/trim seal replacement

[Palmetto Bug]

I need to replace the seals in my tilt/trim cylinders. Already bought the seal kit and an adjustable face pin spanner wrench that wouldn't budge the trim cylinder cap. I'm going to buy the much more expensive but better made Marine Tech spanner wrenches. These are not adjustable and cost $67 each on Amazon but they engage three pins and allow the use of a 1/2 drive socket wrench handle. The trim cylinder caps are a different size than the tilt cylinder so I need two of these wrenches, damn it.

I'm not concerned about the trim cylinder work but does anyone know if I can get the tilt piston out without yanking the whole motor transom bracket off? The tilt cylinder cap seal is leaking but it can't be removed over the end of the piston shaft without pulling the whole piston assembly out.

[mudflat]

Remove the whole unit and access all pistons, you do not have to remove the motor.

[mudflat]

FiveStar Marine has the video on Youtube.

[triplebeard]

Is there a difference in trim units between 2 & 4 strokes? I made a wrench for the trim cylinders on my 2 stroke 90. Piece of flat stock with a hole drilled into it big enough to slide over the shaft. Holes drilled for the engaging pins which I made out of drill bit shanks. Slid those into the pre-drilled holes and welded in place. I'm heading to Summerville tomorrow and can bring it if you'd like to try it.

[Palmetto Bug]

Thank you for the kind offer but I already broke an adjustable wrench. One cylinder has decided to be stubborn. The ones I'm going to buy are overbuilt and have replaceable pins. They also engage three holes at once. I need two different sizes. 32x4mm for the trim cylinders and 38x4mm for the tilt cylinder.

I'm hoping that once I remove the wrist pin from the tilt ram, I can tilt the engine up enough to allow room to pull the tilt piston out of the cylinder. I found a youtube video that showed a guy removing the whole unit. He had to unbolt one side of the transom bracket from the transom and bump it over to make room for the trim unit to come out.

[willyworm]

Unless someone knows a trick I'm quite certain you're gonna have to remove the motor from the transom to open up the clamps and remove the unit.

Every time I've rebuilt one I removed it. All the work to remove it will make the job easier and help ensure you get it done right. I hang the motor from an eyebolt screwed into a ceiling joist in the garage and use a hand winch.

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[triplebeard]

Who said anything about an adjustable wrench? The one I made engages 3 holes at the same time with zero slop and is long enough to create leverage. Good luck with it. You'll have fun refilling the reservoir and getting the air out of the hydraulic fluid. It wasn't as easy as the YouTube video I used.

[Palmetto Bug]

Unless someone knows a trick I'm quite certain you're gonna have to remove the motor from the transom to open up the clamps and remove the unit.

Every time I've rebuilt one I removed it. All the work to remove it will make the job easier and help ensure you get it done right. I hang the motor from an eyebolt screwed into a ceiling joist in the garage and use a hand winch.

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I can't hang the engine without removing the poling platform. The bolts on that are damn near impossible to reach and only accessible through an 8x16" deck hatch in the splash well. I found a video that showed a guy removing the tilt/trim unit by taking only one side of the transom bracket loose and bumping it over enough to get the unit out. I couldn't find a youtube at the link mudflat suggested but I did find that they have refurb units with a two year warranty for a smidge less than $500.

I got the spanner wrenches with Amazon free prime delivery next day! 2019-07-22 08.04.26.jpg

I've already been through the refilling and bleeding routine just keeping the thing working. One thing that made that easier was a long nozzle that fits on the ATF bottle.

The video that Mergie posted about replacing the trim motor in a separate thread is worth watching even if you don't own a boat.

[willyworm]

That makes sense. I didn't think about only taking one side of the the clamps loose.

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[mudflat]

The one I suggested sounds like the one you found. He unbolted one side.