2004 Tohatsu MFS30A 4 stroke Power Tilt Trim (PTT) Problem

dranreb1

Recruit
Joined
Nov 17, 2018
Messages
4
Hello all, I purchased a 2004 30hp Tohatsu and when testing the PTT at a full 90 degree angle (Horizontal) position to ensure the tilt stopper assembly would engage, the PTT piston rod bent and snapped the top eye bush securing bolt. The cause being a rusted steel cylinder pin upper, which did not rotate in the nylon bushings secured in an aluminum eye bush. Painful and costly lesson learnt the hard way, which in hindsight what I will do next time is to fully test the test tilt when purchasing an outboard at the full 90 degree position and not a general 20-40 degree test on an outboard stand. My fault completely as I purchased the outboard in 2014 in CT when I was working in the U.S. and only tested it to about 40 degrees tilt. Only now in Oct 18 have I fitted it to my boat back in Western Australia and fully tested the PTT.

Thinking I could replace the hydraulic piston in the cylinder, proved incorrect, as you have to buy the whole PTT assembly Part No 3ROS77150-0 at around $2000 AUD.(Throw away and replace item).
I was informed that Mercury /Mariner do a similar PTT for the 2004 model, which the piston rod and sub components can be replaced, but the components where also around $1000 AUD. After much research and contacting agents and wreckers, my solution was to purchase a Honda 15-30 HP 4 stroke SHOWA PTT twin leg unit second hand for $300 AUD and fit it to my Tohatsu. The issues I had upon fitment were
1. The original Tohatsu bottom securing bolt with washers and circlips was used instead of the Honda unit, I used the Tohatsu outer bushings, but used the Honda inner bushings
2.The Honda top eye bushing was replaced with the Tohatsu eye bushing as well as the original cylinder pin upper.
3. The Blue and Green electrical wires were reversed on the switching relays in the motor control box, ie on the Tohatsu, Blue was upper, Green was lower, the Honda unit was reversed.
4. The full extension of the Honda piston rod at full 90 degree tilt is slightly less than the Tohatsu, so the tilt stopper assembly was trimmed to fit, but not degrade safety.

Additional comments: The only other minor thing was that the fill hole on the Honda tilt trim motor is 180 degrees from the original, ie faces the front of the boat, so if you have to fill the reservoir you will need to either undo the top cylinder pin upper or remove the complete unit. I tested the level before fitment, as I also wanted to see the colour and purity of the fluid as it was a second hand unit. Another advantage now of having the Honda Showa unit is I can rebuild the unit if I experience any leakage issues.

Hope this helps anyone else who has the same issue,
Cheers Bernie.
 

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pvanv

Admiral
Joined
Apr 20, 2008
Messages
6,500
Bernie,

Glad you got it working.

Apparently Australia handles things differently than in the US. For the MFS30A, the original TT unit 3R0S771501 is out of stock (and may not be re-stocked in the US), but the earlier unit is available, and will fit.
3AC771511MPOWER TRIM & TILT ASSY$1,208.33
Is the proper replacement part will work if 3GF624661M tilt stopper is used.

The long and the short of this is to not neglect maintenance. A little lube might have prevented the whole problem.
 

dranreb1

Recruit
Joined
Nov 17, 2018
Messages
4
Thanks Paul for the alternate part no, since I only paid around $2K for the outboard, it makes better value for money sense to buy another outboard than spend that much on another PTT. I think buying a second hand unit for $300 AUD I got out of it fairly lightly. You are correct on the lubrication maintenance issue, something I am religious at doing, however the top pivot pin was painted over and did not show the tell tale rust issue, so I missed it. If I had tested the PTT on purchase at the full extension I might have seen the issue earlier. Be assured all the rotating pins, ie bottom pin, tilt stopper, top eye pin have been disassembled, cleaned lubricated and replaced and the tattoo is on the arm to remind me in the future !!

Cheers Bernie.
 
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