1986 Tohatsu M70A2 power tilt/trim PLEASE HELP

Hello all! I am a mechanic and recently had a buddy bring me his 1987 skeeter with an '86 Tohatsu 70hp that has power tilt/trim and cooling issues. I'm pretty sure the model is an M70A or M70A2. I've dealt with running issues and electrical portion of tilt/trim problems and drained old fluid from trim pump, added new and bled the system. I am not super familiar with the hydraulics in tilt trim systems however am very familiar with machinery hydraulics and how they work. At this point I am certain that the remaining problem lies in the hydraulic circuit. The electric motor functions in both directions(up and down) and sounds like it is healthy but it sounds as though it has 0 resistance in the circuit. I am familiar with how it should sound under load and it is way to high pitched as the motor is clearly spinning at max rpm with 0 resistance. After opening up the pump housing and taking a closer look I noticed that with the manual release valve closed and seated tightly the port to the reservoir portion was not closed off. This would seem to clearly explain why it is not working and why it sounds like the motor is spinning with no resistance in my mind. After removing and looking a bit closer at the release valve it seems to me there may be some parts missing. I told the owner my concerns and he informed me that he had halfhazardly removed the valve prior to bringing it to me at which time he realized that is the exact moment the trim stopped working! At this point I believe there is a shuttle valve missing like several other manumanufacturers manual releases make use of. My problem is I don't know what all is missing if anything and if I can make the parts, since I have discovered finding parts for this unit is next to impossible, how they go back together! Also when we opened the pump housing and removed the pump from the cap we ended up with a stray baring landing in my parts catch and I haven't been able
to determine where it belongs either. If anyone has an exploded parts diagram for this unit and any information or advice you can lend it would be greatly appreciated!

Although quite obsolete, a few parts are available... but pretty much no bits for the PTT. The A2 had an additional ring on each piston, but was otherwise identical. I have a reprint Factory service manual available. Your best bet would be to get a used one (45A2, 50C, 60A, or 70A2) that has a bad power head or bad LU, and salvage the PTT parts from it. At issue is that a suncontractor made the PTT units, and they are basically NLA. The parts catalog for the 70A/A2 does not list separate parts for the PTT unit, but some of the newer units are similar. This the diagram from a 70C:

pvanv said:

Although quite obsolete, a few parts are available... but pretty much no bits for the PTT. The A2 had an additional ring on each piston, but was otherwise identical. I have a reprint Factory service manual available. Your best bet would be to get a used one (45A2, 50C, 60A, or 70A2) that has a bad power head or bad LU, and salvage the PTT parts from it. At issue is that a suncontractor made the PTT units, and they are basically NLA. The parts catalog for the 70A/A2 does not list separate parts for the PTT unit, but some of the newer units are similar. This the diagram from a 70C:

View attachment 24979

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Hey Paul!
Thanks so much for the info you shared. I figured that is what I was going to find out simply from how much looking I have done with little to no success at finding anything but vague used parts and a very little specific info! How can I get my hands on a factory manual reprint like you speak of? That would be handy just for general reference!

Capn Jonesy said:

Hey Paul!
Thanks so much for the info you shared. I figured that is what I was going to find out simply from how much looking I have done with little to no success at finding anything but vague used parts and a very little specific info! How can I get my hands on a factory manual reprint like you speak of? That would be handy just for general reference!

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Drop me PM or email p.van.v at verizon dot net

Hi there, I am not sure if this is permitted or not, but I happen to have a spare trim motor/pump assembly, if you need it, let me know - I can ship it to you for a couple of bucks. (it's the external motor that mounts on the left side of the outboard).

Did you ever get your trim issue worked out? I had to replace my pump with another model that was for a Johnson. BE glad to share the process. Was alot cheaper too. Amazon - only like $150 for new one.

Vettera said:

Did you ever get your trim issue worked out? I had to replace my pump with another model that was for a Johnson. BE glad to share the process. Was alot cheaper too. Amazon - only like $150 for new one.

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Can you tell me more? I'm looking at having to replace mine too

LundProV said:

Hi there, I am not sure if this is permitted or not, but I happen to have a spare trim motor/pump assembly, if you need it, let me know - I can ship it to you for a couple of bucks. (it's the external motor that mounts on the left side of the outboard).

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Still have this?