Trim goes up but not down and sounds like its working?

[acuraguy81]

Re: Trim goes up but not down and sounds like its working?

shuttle valves rarely stick. they commonly have 20-100 times more square inches than the poppet. In many OMC systems, the shuttle doesn't even have a sealing oring.
common hydraulic problems that cause a failure to lower .... debris gets stuck in one of the fluid intake balls and the gearplate simply pumps the fluid through both inlets without generating any pressure - the manual release valve is a tapered plug with two or more oring that separate the up, down, and bypass circuits. If the MRV becomes damaged it can short out the down and bypass circuits causing a system to lift but not lower - the system does not have a tilt limit and is raised hard against its stop creating extremely high internal pressure. a typical pump will have 20-30% higher pressure when the trim motor is spinning. When the pump spins in opposite direction the internal bypass or regulator on down circuit pops open before overcoming the internal pressure in up circuit.

I think, Don is most likely right in his initial analysis. If the motor is spinning but the system won't lower then look for mechanical problems first. when pumps break they usually bleed off pressure and gravity pulls down the engine on its own.

So If I loosen the lines on the rams and put pressure on the drive the motor should come down?

 

[achris]

Re: Trim goes up but not down and sounds like its working?

So If I loosen the lines on the rams and put pressure on the drive the motor should come down?

Yes. If it doesn't, most likely you have one (or both) end cap seals leaking and the corrosion has 'grabbed' the piston rod... That means R&R the end cap...

Chris......

 

[acuraguy81]

Re: Trim goes up but not down and sounds like its working?

OK I got the boat out of the water and the outdrive had some upward trim left in it. I could trim it up and back down to the spot it is stuck at, it seemed to come down a little further while doing this but not much at all it still it sticking at that certain point. I did have a friend putting his body weight on the drive at the same time.

 

[Don S]

Re: Trim goes up but not down and sounds like its working?

Disconnect both trim rams from the back of the drive and trim down. Do both rams retract? If only one does, when it gets all the way down does the pump sound change and the other ram not retract?

 

[acuraguy81]

Re: Trim goes up but not down and sounds like its working?

Disconnect both trim rams from the back of the drive and trim down. Do both rams retract? If only one does, when it gets all the way down does the pump sound change and the other ram not retract?

So I took off both fluid lines from the rams that would allow the trim to go down. When I use the trim switch both lines blow fluid out of them. But both rams when the lines are hooked up do not fully lower? One ram seems to lower a bit more than the other one but still does not lower near all the way.

 

[Bondo]

Re: Trim goes up but not down and sounds like its working?

So I took off both fluid lines from the rams that would allow the trim to go down. When I use the trim switch both lines blow fluid out of them. But both rams when the lines are hooked up do not fully lower? One ram seems to lower a bit more than the other one but still does not lower near all the way.

Ayuh,.... The ram that Don't wanta lower is yer Bad ram.... It's holdin' up it's mate...

It's probably corroded 'round the gland collar...

 

[dubs283]

Re: Trim goes up but not down and sounds like its working?

One ram seems to lower a bit more than the other one but still does not lower near all the way.

not connected the rams usually will move at different speeds, but seeing as how you have to force them down when connected, the issue is most likely a sticking seal in one end cap/corrsion on the ram or an internal issue

you can get rebuild kits for the rams, seals, o-rings, internal components, etc...

 

[acuraguy81]

Re: Trim goes up but not down and sounds like its working?

not connected the rams usually will move at different speeds, but seeing as how you have to force them down when connected, the issue is most likely a sticking seal in one end cap/corrsion on the ram or an internal issue

you can get rebuild kits for the rams, seals, o-rings, internal components, etc...

They both dont move all the way down one just goes a bit further than the other. Should I be able to move the ram by hand to see if it is jammed?

 

[dubs283]

Re: Trim goes up but not down and sounds like its working?

Should I be able to move the ram by hand to see if it is jammed?

you should not be able to move either ram by hand at all, unless something is leaking externally or internally

get a rebuild kit, it will solve your issue

 

[acuraguy81]

Re: Trim goes up but not down and sounds like its working?

you should not be able to move either ram by hand at all, unless something is leaking externally or internally

get a rebuild kit, it will solve your issue

I can get a used one from one of the local shops. How if the world do I get the pin out that is attached on the bottom side of the ram nearest to the transom of the boat? Ive tried lots of heat with map gas and no luck also soaked it good with PB Blaster.

FYI the other ram works great goes all the way up and down. The broken one only goes up to a point and sticks then goes back down to another point and sticks. So the plans are to just replace the bad ram with a good used one, but the dang pin is a huge hurdle!!:mad-new:

 

[acuraguy81]

Re: Trim goes up but not down and sounds like its working?

I can get a used one from one of the local shops. How if the world do I get the pin out that is attached on the bottom side of the ram nearest to the transom of the boat? Ive tried lots of heat with map gas and no luck also soaked it good with PB Blaster.

FYI the other ram works great goes all the way up and down. The broken one only goes up to a point and sticks then goes back down to another point and sticks. So the plans are to just replace the bad ram with a good used one, but the dang pin is a huge hurdle!!:mad-new:

BUMP I need the pin out to swap my ram.

 

[achris]

Re: Trim goes up but not down and sounds like its working?

BUMP I need the pin out to swap my ram.

Remove the hydraulic lines, undo the nut, take the washer off, pull the ram off the rubber bushings...

Chris........

 

[dubs283]

Re: Trim goes up but not down and sounds like its working?

Remove the hydraulic lines, undo the nut, take the washer off, pull the ram off the rubber bushings.

pretty sure they've got gen 2's

it would be remove the end cap, e-clip and washer to get the ram off the gimble housing, just like the aft pin assy

 

[acuraguy81]

Re: Trim goes up but not down and sounds like its working?

pretty sure they've got gen 2's

it would be remove the end cap, e-clip and washer to get the ram off the gimble housing, just like the aft pin assy

I understand what you all are saying that is easy. How ever the pin is so corroded that I can not get it to budge. How can I get it out? I know about the eclips give me a little credit.