Re: Newbie with Johnson 70hp power tilt/trim question.
I appreciate the reply "RRITT" Motor will stay up but something is wrong somewhere in it.I've tried everything and still when the weight of ob is on the tilt shaft it goes up and down but the trim does'nt work right it takes forever to go all the way down.but if i disconnect ob motor from tilt shaft and go up and down with switch the tilt stops working and the trim starts working. They come out together at same time but did notice they go back down one at a time.I don't know what the deal is.I even tried back bleeding it and still nothing.Either there is still alot of air or something is clogged or the trim side is just shot.I tried to crack the trim cylinder caps loose to free any air but could'nt get them to budge.Im at my witts end.Guess ill just have to shell out $2-300 for another unit.
my previous reply may give some insight but does not actually apply to your system. I incorrectly assumed 1980 would be the twin ram system. On a three ram system all three rams are connected to the same fluid pressure. If one of them jams then the other two move faster. By the same token, if one of them has a broken oring then none of them will lift. When normally lowering, the engine is pushing down on the tilt piston and the trim pistons won't move until the engine is also pushing down on them. When going up, the weight of the engine causes all three pistons to lift in unison until the trim pistons can't extend any further. When the trim piston are fully extended then all the fluid is diverted to the tilt ram and the engine appears to lift much faster.
Trim systems are generally filled when fully raised. This is because the raised position requires more fluid in the rams. Many systems will run out of fluid if filled when lowered. Those same systems are pressurized when lowered and the air in reservoir shrinks to accomodate extra fluid (the rams have less fluid in them when retracted and the unused fluid is pushed back into reservoir). Please consult your manual. If you remvoe the filler cap in wrong position then you could end up injured or with a face full of oil. Some trim systems have oversized reservoirs and are filled when lowered. These systems tend to develop a negative pressure in reservoir and generally don't last as long because they suck moisture in through motor seals.
As regards your system, maybe I don't understand because I'm not seeing anything wrong with your description. It is normal for trim pistons to stick or retract differently if they do not have weight of engine. If they misbehave with weight of engine on them then it is usually lack of pressure from pump or mechanical sticking in trim cylinder (or transom brackets). Lack of pressure from pump should create drift down problems while mechanical problems don't.
