help with tilt and trim

graybird78

Seaman Apprentice
Joined
Aug 14, 2016
Messages
38
i need help with tilt and trim for my 1990 90hp us marine built engine. the model #906X90C. the tilt and trim on my motor bleeds down after a few minutes. i'm sure the pump is the cause. i also have another complete tilt and trim with the same model number ,same year and hp. it has a completely different pump and motor assembly.the pump and motor are 1 unit. it needs the tilt cylinder rebuilt . i cant identify the system. anyone know what it would be. any help would be great.
 

jerryjerry05

Supreme Mariner
Joined
May 7, 2008
Messages
18,075
Any pics would really help.

The old style T@T the seals need replacing.

The newer needs to be taken apart to replace the seals.
Depending on the leak?? it might be a seal problem or corrosion problem.
My 225 tilt ram was a salt water motor, the area around the seal was corroded and needed to be replaced.

There is a fairly detailed post in the first few questions of this forum.
 

graybird78

Seaman Apprentice
Joined
Aug 14, 2016
Messages
38
jerry, not able to posts pics.best way to describe the differences is my original t&t has horizontal metal lines going into the side of pump housing. the pump motor and pump are bolted together. also the pump motor is short fat and round with 2 wires with spade connectors.the other t&t unit the pump and motor are 1 unit, not separate. the lines mount verticle into pump. also the motor is taller and thinner than my original. 2 wires with barrel connectors.
 

graybird78

Seaman Apprentice
Joined
Aug 14, 2016
Messages
38
up date, now i have my boat back. i have 2 tilt and trim units. my original unit is blue in color. my spare is dark gray. they work different from each other. my blue unit when working ,the trim ram comes out till it stops then the tilt ram lifts the motor. my spare unit the trim ram and the tilt ram work at he same time. will try to figure out how to get pics on here. i cant find any pics of the dark gray unit.
 

graybird78

Seaman Apprentice
Joined
Aug 14, 2016
Messages
38
i think i finally identfied my spare tilt and trim unit i think it is a mercury pump part number 819762a4
 

Jiggz

Captain
Joined
Oct 23, 2009
Messages
3,909
Please post pics of the two units so it can be identified accordingly. Based from your post the original seems to work properly, i.e. trim first and then the tilt when going up and in reverse order when coming down.

The leak down is not necessarily, although most of the time it is, caused by the valve body or pump. Sometimes, it can be a leaky tilt or trim cylinder. There is a procedure in one of the sticky posts to test which part is causing the leak down.
 

graybird78

Seaman Apprentice
Joined
Aug 14, 2016
Messages
38
will try to load pics . i finally used the spare tilt and trim, hooked everything up and it works perfect.
 

Jiggz

Captain
Joined
Oct 23, 2009
Messages
3,909
Well, if the spare T&T works perfectly I guess that solves your problem and no need to post anymore pics. Have a great boating season.
 
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