1983 Mercury 115 hp outboard Trim problem, detailed troubleshooting inside

humidex

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1983 Mercury 115hp 6 cyl with what I believe is a dual solenoid trim pump.

The motor is currently stuck up. I've tried the following

1. Trying to lower the motor with the trim, trim pump runs, i can see a hose "flex" and move but nothing happens, I cannot trim anymore up (nothing happens, I think its at a limit?)

2. I tried the manual release on the trim pump itself and the motor still WILL NOT move down. I find this the most troubling... is it stuck?

3. I tried to bleed off possible air in the system via the up and down bleed screws on both cylinders, no air present.

4. I topped up the oil, took maybe 50-60ml of oil and was full, attempted bleed again and still isnt working.

it was working fine, stopped stuck up, got it home and was able to trim it down and up and havent been able to move it since.

Possibly the trim pump itself? or can the cylinders get stuck? I have both cylinders off their bolts now and when I run the trim down still nothing happens.

Please help...
 

achris

More fish than mountain goat
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Re: 1983 Mercury 115 hp outboard Trim problem, detailed troubleshooting inside

Hello Humidex, and :welcome: to iBoats...

Do you have an engine serial number there?

If you took the bolts out and the engine came down, but running the pump didn't retract either of the cylinders, then it sounds like the problem is the check valves in the pump....


Chris.....
 
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humidex

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Re: 1983 Mercury 115 hp outboard Trim problem, detailed troubleshooting inside

Hello Humidex, and :welcome: to iBoats...

Do you have an engine serial number there?

If you took the bolts out and the engine came down, but running the pump didn't retract either of the cylinders, then it sounds like the problem is the check valves in the pump....


Chris.....

Serial 7200742

The cylinders will not extend to bring the motor down, I had to physically unbolt them to get the motor down. It worked again once down and up and now will not work again.

Would this be 100% a problem with the trim pump? its full of oil, ive bled everywhere i can see and no air came out.

What i find troubling is when I undid the thumbscrew on the trim pump to allow the motor to fall manually, i couldnt get it to budge!
 

Chris1956

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Re: 1983 Mercury 115 hp outboard Trim problem, detailed troubleshooting inside

That motor has the PTT pump in the boat right? Crack one of the hydraulic lines and let the oil leak out. The motor should go down. Those "dog ear" tilt locks are not jamming it up, right?

After it is down, make sure the manual release is all the way CCW, and retest PTT function. if it still doesn't work properly, the control valve could be bad, or the pump could be bad.
 

humidex

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Re: 1983 Mercury 115 hp outboard Trim problem, detailed troubleshooting inside

That motor has the PTT pump in the boat right? Crack one of the hydraulic lines and let the oil leak out. The motor should go down. Those "dog ear" tilt locks are not jamming it up, right?

After it is down, make sure the manual release is all the way CCW, and retest PTT function. if it still doesn't work properly, the control valve could be bad, or the pump could be bad.

Yes the PTT pump is in the boat with four hoses going to the two cylinders, I will try and fully take the oil out of the lines and hopefully it falls. Yes I took the dog ears out of the picture, it is totally hanging on the two cylinders.

I have both a trim up and down and a trailer up and down, neither work.

Its probably the pump or valve like you said :( $900 new at my dealer
 

Chris1956

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Re: 1983 Mercury 115 hp outboard Trim problem, detailed troubleshooting inside

Aftermarket pumps used to be avail for than motor. However, there were two that looked almost identical. If you locate one, take you broken one with you and make sure the armature of the motor is the same length.

Of course, you could take the pump/reservoir to a elec motor shop. Maybe they can fix it up?
 

humidex

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Re: 1983 Mercury 115 hp outboard Trim problem, detailed troubleshooting inside

well the motor works great... after ive taken it all apart i have to say its most likely the control valve assembly.

The problem is, I don't know where to get one... part# 45197A 2

I have been looking for a replacement control valve, but it says that the part is obsolete. Does this mean that I will have to buy the whole assembly. If so I am in trouble. I don't think that I can afford a new pump Any suggestions? CONTROL VALVE ASSEMBLY
List Price: $380.30
Price: $380.30
You Save: $0.00

PRODUCT OBSOLETE
45197A 2 Control Valve Assembly
 

achris

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Re: 1983 Mercury 115 hp outboard Trim problem, detailed troubleshooting inside

ebay
 

humidex

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Re: 1983 Mercury 115 hp outboard Trim problem, detailed troubleshooting inside

found a trim pump assembly off ebay for a 1977 115hp I have a 1983... ive been scouring the net to see if they are the same part but with zero luck... its like they almost dont want you to know!
 

humidex

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Re: 1983 Mercury 115 hp outboard Trim problem, detailed troubleshooting inside

i have a picture of them both and at least the bottom assembly looks the same... I cannot pull the parts catalog for the 1977 115hp ELPT online for some reason though!! @#$@#
 

humidex

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Re: 1983 Mercury 115 hp outboard Trim problem, detailed troubleshooting inside

hmmm well apparently its not the same total assembly BUT the bottom half seems to be the same control valve assembly...
 

achris

More fish than mountain goat
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Re: 1983 Mercury 115 hp outboard Trim problem, detailed troubleshooting inside

hmmm well apparently its not the same total assembly BUT the bottom half seems to be the same control valve assembly...

Correct, the control valve IS the same.... (Part# -45197A2)
 

racerone

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Switch the blue and green wires on the trim solenoids and post what happens.
 
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