1988 tohatsu 70HP power tilt and trim

charles2955

Recruit
Joined
Sep 2, 2009
Messages
1
I have a 1988 Tohatsu 70HP motor. I am having problems with the power tilt and trim not lifting or lowering. The motor runs fine with no binding sounds etc. I broke the pump down, put it back together and used 32W hydraulic fluid to fill the reservoir, put the screw in the manual position and raised and lowered the motor to bleed out air. Still, I can not get it to raise or lower. When reading other answers it seems as if I was supposed to use transmission fluid. Is this correct and what weight? Thanks for any help.
 

DaveTrig

Recruit
Joined
Sep 3, 2009
Messages
3
Re: 1988 tohatsu 70HP power tilt and trim

The manual for my 70A2 says to use automotive automatic transmission fluid. I don't think that comes in different weights.
 

kaferhaus

Petty Officer 1st Class
Joined
Dec 17, 2008
Messages
250
Re: 1988 tohatsu 70HP power tilt and trim

you probably discovered this long ago..... but there's a bypass screw on those...it's likely turned to bypass so the motor can be tilted by hand... you can run that pump until you're blue in the face and the fluid will just run in circles instead of through the cylinders....
 

rogierbanis

Cadet
Joined
Sep 2, 2010
Messages
6
Re: 1988 tohatsu 70HP power tilt and trim

Hi,

I also have a Tohatsu 70HP with power tilt. Engine is from 1999.
For me also the powertilt motor works but leg does'nt go up.

I filled the system with ATF oil. Oil immediately came out on the left of the system, looking from the back of the boat.
When inspecting i noticed there was a round whole on the left side. Looks like there should be a plug or something in it. Problem is that i can's see it very well.

Can someone confirm or deny that there should be a plug or something like that on the left side of the hydrolic system?

Thanks.
 

rogierbanis

Cadet
Joined
Sep 2, 2010
Messages
6
Re: 1988 tohatsu 70HP power tilt and trim

I took off the whole ptt system and indeed there should have been a plug. The `o-ring was still inside.
I cleaned the whole system since it was full of water now and put it back on.
I fulled up the reservoir with ATF oil and started the air bleed procedure.

Now, a few days later, there is only a small amount of oil in, around 300ml = 17Oz or so, so not enough oil yet.
I hear air in the system but whatever i do i just can't seem to get the rest of the air out.
What i do is this, open the manual, bring ram up and down a few times. Put it up. Top off the oil. Bring it up and down again a few times. Let it stand for a few hours. Put it back up. Try to top off oil again but nothing goes in. Reservoir is still full.

Am i doing something wrong or is it just taking more time?

What surprises me is that i can't put any extra oil in.

The up and down procedure of the engine should be done with the manual valve open i suppose?
 

rogierbanis

Cadet
Joined
Sep 2, 2010
Messages
6
Re: 1988 tohatsu 70HP power tilt and trim

Hi,
I am still working on this issue and still is not solved.
The engine does tilt up now but not down. The tilt motor sounds good but nothing happens.

Can this still be air since it does trim up? When I open the manual valve to let the engine come down again I hear a lot of air bubbles when the engine reaches it's lowest point.

Does Nyone have a clue what more to look for or try?

Thank you very much for any reply.

Best regards,
Rogier
 

pvanv

Admiral
Joined
Apr 20, 2008
Messages
6,500
Re: 1988 tohatsu 70HP power tilt and trim

Try bleeding some more air out. Use ATF -- it helps to prevent sticking valves. If the water intrusion caused rust in the system, YMMV.
 
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