power trim on 75 hp

zzimmer3

Seaman Apprentice
Joined
Sep 30, 2012
Messages
35
I just mounted and wired up my 75 hp mariner, initially the power trim worked fine, now that its in the lowered position, it won't go up. i can hear the soliniod actuate, and it sounds like the trim motor is running (kinda funny sounding), but it only moves about half inch up or so. from the manual, it says not to open fill plug in down position, so i can't verify level? thanks for the help.
 

allycat1521

Cadet
Joined
Oct 1, 2012
Messages
7
Re: power trim on 75 hp

there is a manual release on the starboard side lower clamp bracket that u can turn out to manually lift ur motor in the the upright position to check your oil level. caution that you don't want to turn it all the way out as to cause damage to the manual release, only turn out until you can lift the motor or until the washer on the manual release just touches the bracket, hope this helps.
 

zzimmer3

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Sep 30, 2012
Messages
35
Re: power trim on 75 hp

Thank you, I see the screw, and also looked in manual to verify its location. I'll get to it tomorrow. thanks again
 

zzimmer3

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Sep 30, 2012
Messages
35
Re: power trim on 75 hp

I have put the motor all the way up, put up the lever that keeps it from coming down, checked the fluid level, which was full. the darn thing won't go up or down (I flipped the lever back down), but it won't move at all. the motor (power trim) is running, but nothing is happening. is the pump bad? i haven't even used the boat or motor, it was working fine, and just stopped???? thank you for the help
 

RRitt

Captain
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Mar 30, 2006
Messages
3,319
Re: power trim on 75 hp

motor runs, fluid full, trim doesn't move.

that is almost always a broken pump. However, sometimes it is a brand new trim motor installed with the wrong drive shaft length. There are four different motors and four different pumps. When you buy a new electric motor the old shaft might be too short and the motor spins without being in gear. That is first thing to check if you see a new trim motor. If it is not a shiny new motor then the pump is broken. i think pump+manifold is NLA from dealers. check ebay for old stock or rebuild service.
 

zzimmer3

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Sep 30, 2012
Messages
35
Re: power trim on 75 hp

Since I know its not new, its been the same pump/motor since my dad has had it and it worked up until last week-i'm inclined to think its a broken pump, as you stated. I will start hunting around for one. thank you for your help. i appreciate it.
 

zzimmer3

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Sep 30, 2012
Messages
35
Re: power trim on 75 hp

to remove the motor/pump from the power trim, is there some secret? it appears that i must move the cylinder out of the way by disconnecting it from the piston end, swinging it down, and move the motor away from the transom to gain accsess to the back screw of the motor on the trim assembly. i'm guessing this is going to be somewhat of a pain. thank you if you have any advice in changing this out.
 

RRitt

Captain
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Mar 30, 2006
Messages
3,319
Re: power trim on 75 hp

I'll assume it is the all-in-one single ram trim system.

lift engine and block into place
drive out upper cotter pin (looks like a nail)
remove upper mounting shaft
drive out lower cotter pin
remove lower mounting shaft
disconnect wiring and remove unit as a whole
 

zzimmer3

Seaman Apprentice
Joined
Sep 30, 2012
Messages
35
Re: power trim on 75 hp

yes, single ram, looking from the rear, the motor is on the right, fluid resivior on the left. all snuggled in nice and tight!lol.
 

RRitt

Captain
Joined
Mar 30, 2006
Messages
3,319
Re: power trim on 75 hp

that sounds like a three ram. one attached cylinder in center and two short stubby pistons not attached. you have to unbolt those. It is a more difficult rebuild than the single ram. I didn't know they used that system on a 75. its kind of overkill.
 

zzimmer3

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Joined
Sep 30, 2012
Messages
35
Re: power trim on 75 hp

yes, thats what it is, i forgot to mention the stubby little ones. i hope to work with it sunday (can't spend all my free time out there, mama gets a little irratable if i'm out there to much).
 

zzimmer3

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Sep 30, 2012
Messages
35
Re: power trim on 75 hp

I have the pump/motor assembly removed. I've found several on ebay, about $150 appears to be the cheapest. before moving forward with this purchase, I'd like to reassure myself that i need to spend this money. The trim worked at first, but just stopped, initially it would go down, but not up. the motor would (and would still before i removed it) run, but it kinda sounded like the pump was cavitating. then the down stopped working also. the same noise, kinda like a growling/cavitating sound. I read in another post that generally a cleaning and flushing will cure some problems. or is this a broken pump, as RRitt said? thank you, your advice has helped me greatly so far.
 

zzimmer3

Seaman Apprentice
Joined
Sep 30, 2012
Messages
35
Re: power trim on 75 hp

with the motor out, it is engaging and turning the pump head shaft (while pressing up or down). i can also tell its driving the gear/shaft off the main shaft. i can see a female hex head turning. so it is driving, although it may not be doing what its supposed to. thanks
 
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zzimmer3

Seaman Apprentice
Joined
Sep 30, 2012
Messages
35
Re: power trim on 75 hp

i've removed the pump head from the motor. i disassembled the pump head, found that both the drive gear and driven gear are good. the springs and balls seem ok. i didn't find or see any blockages. o rings seem good. i put it back together, and hooked it up to the motor and put the pump head in a container of dextron fluid, and it pumps in one direction, but it doesn't seem to in the other (fluid moves out of a port in the side of the pump going one way, but out a port in the face of the pump while going the other). i'm not sure if i'm seeing that correct or not. i'm going to clean out the entire resivoir assembly on the transom. maybe a blockage from sitting for a couple of years?
 

RRitt

Captain
Joined
Mar 30, 2006
Messages
3,319
Re: power trim on 75 hp

if you have winter ... order an oring or seal kit from mercury. I'm guessing 48462A2 or something similar. They run about $70. then just take your time to carefully rebuild it. I think your system may also be the one where you can buy a motor+pump for under $300. cleaning a system and putting back together without any new parts almost never works.
 

zzimmer3

Seaman Apprentice
Joined
Sep 30, 2012
Messages
35
Re: power trim on 75 hp

thank you rritt. i found the oring kit you suggested, and will order it and hope that fixes my problem. thank you for your trouble
 

zzimmer3

Seaman Apprentice
Joined
Sep 30, 2012
Messages
35
Re: power trim on 75 hp

i found a new motor and pump for $150 on ebay (new), it is installed and working great. thank you all for your help.
 
M

Maxz695

Guest
Re: power trim on 75 hp

great job enjoy the boat. You earned it
 

zzimmer3

Seaman Apprentice
Joined
Sep 30, 2012
Messages
35
Re: power trim on 75 hp

I finally get to install the freshly rebuilt lower unit, which I stressed out about, just to find the power trim failure. so now it may be a bit chilly, but my father and I enjoy cold runs down the river, sight seeing (always his boat in the past though). thanks all.
 
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