1996 Force 120 Trim Pump help

H

henryo

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Sorry in advance as this is my first post. I just bought my first boat and it came with one small issue. It needed a new trim pump. So having worked on cars I figured it was something that was within my skill set. So what I need to know is this. What is the absolute minimum I need to do to get that trim pump off? That is besides taking it to a local mechanic who is two to three weeks behind schedule and charging 90 bucks an hour.

I've removed the pin that holds the pump arm to the lower unit. I see another one of those big pins underneath the pump that is held in place with a small vertical pin. I've removed the vertical pin and tried to pound out the bigger pin. Only problem is that it is not budging one bit. Am I trying to remove the wrong thing? Can anyone give me some pointers? If so I would be very appreciative.

Thanks
Dan
 
R

RRitt

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Re: 1996 Force 120 Trim Pump help

there are two parts to a trim pump assembly. The first part is the electric motor which provides a spinning shaft. The second part is the pump itself which turn the spinning shaft into hydraulic pressure.

Now ... do you need a pump or a motor?

The motors are affordable to buy or rebuild. The pumps are not. In fact, if you have an oildyne pump it is cheaper to throw it away, buy a used Eaton, and rebuild the Eaton to be like new. Mercury rapes you so bad on oildyne parts that it should be illegal.

so ... do you need a motor or a pump?

If motor, then you leave pump in place and take loose the four corner bolts.
 
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henryo

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Re: 1996 Force 120 Trim Pump help

It's the motor. The problem is getting to the 4 corner bolts. The two nearest the transom are pretty hard to get to. One is actually under the frame. Without taking the motor off the transom how can I get to these?
 
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RRitt

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Re: 1996 Force 120 Trim Pump help

When stainless and aluminum are placed in saltwater they become a very weak battery. Over time the stainless will completely destroy the aluminum. The aluminum turns into a white deposit. Every teaspoon of aluminum becomes ten teaspoons of white residue. If you are unlucky enough to have this residue form around a stainless shaft as it passes through an aluminum housing then the parts become "fused" together. Actually, they aren't fused. Its just that the aluminum exapnds inside the hole and you can't get it out. If you wait long enough the aluminum will split. **

Sometimes vinegar softens the Al-ox residue. Sometimes it will crack with heat. Sometimes it takes a hacksaw, a drill press, and a stack of carbide bits.

If it is the shaft then it might work better to figure out a way to swap trim motor while it is still on boat.

** in an ironic twist mercury engineers brag that they increased the amount of stainless in their saltwater engines. Hmm... the problem isn't saltwater. The problem is mixing stainless and aluminum. Adding more stainless just makes the remaining aluminum dissolve even more quickly. (Good reason to buy an ETEC instead of a merc?)
 
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henryo

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Re: 1996 Force 120 Trim Pump help

So is the large pin under the trim pump the one I should be removing? If I somehow get this out will the entire pump assembly drop out of the frame? If not is there a way to get to those back bolts.

Thanks
 
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henryo

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Re: 1996 Force 120 Trim Pump help

Also the previous owner of the boat tried to remove the trim motor by attempting to unscrew the bolts on the outside of the transom bracket. Only problem is that the bolts sheared off. I'm assuming this was due in part to the stainless steel and aluminum fusing and corrosion issue.
 
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fab9racing

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Jun 16, 2008
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Re: 1996 Force 120 Trim Pump help

i got the motor off the pump by using a allen bit then i used a then wall 1/4 socket, its pretty simple where there is a will there is a way, good luck
 
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henryo

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Re: 1996 Force 120 Trim Pump help

fab9racing said:
i got the motor off the pump by using a allen bit then i used a then wall 1/4 socket, its pretty simple where there is a will there is a way, good luck
Click to expand...

What did you use the allen bit for?
 
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fab9racing

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Re: 1996 Force 120 Trim Pump help

Well when you asked what the allen was for i figured you must hav bolts, so i looked at a parts break down and i noticed they have 2 designs 1 uses a square type looking pump with bolts and the other is a round style pump with socket head screws, so if you have the square pump i would imagine the 2 bolts next to the hull would be hard to get off
 
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henryo

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Re: 1996 Force 120 Trim Pump help

fab9racing said:
Well when you asked what the allen was for i figured you must hav bolts, so i looked at a parts break down and i noticed they have 2 designs 1 uses a square type looking pump with bolts and the other is a round style pump with socket head screws, so if you have the square pump i would imagine the 2 bolts next to the hull would be hard to get off
Click to expand...

Ya they are darn near impossible to get to without taking out the entire pump assembly or removing the engine from the transom. Plus anytime I try to remove any bolts they just sheer right off. This is turning out to be not such a good situation.

I really hope the engineers that dreamed this up considered a career change.
 
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fab9racing

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Re: 1996 Force 120 Trim Pump help

ya right they are planning their retirement not planning on better outboards
 
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fab9racing

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Re: 1996 Force 120 Trim Pump help

henryo said:
Sorry in advance as this is my first post. I just bought my first boat and it came with one small issue. It needed a new trim pump. So having worked on cars I figured it was something that was within my skill set. So what I need to know is this. What is the absolute minimum I need to do to get that trim pump off? That is besides taking it to a local mechanic who is two to three weeks behind schedule and charging 90 bucks an hour.

I've removed the pin that holds the pump arm to the lower unit. I see another one of those big pins underneath the pump that is held in place with a small vertical pin. I've removed the vertical pin and tried to pound out the bigger pin. Only problem is that it is not budging one bit. Am I trying to remove the wrong thing? Can anyone give me some pointers? If so I would be very appreciative.

Thanks
Dan
Click to expand...
are you sure you need a new pump? i have very rarely seen the pumps bad, its brushes or some type of corrison most of the time, because i think you can change the pump motor by removing the bolts from the top of the motor, just a thought
 
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RRitt

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Re: 1996 Force 120 Trim Pump help

Sounds like a saltwater boat where somebody didn't stay up with the anode and/or didn't like to wash after use. If you aren't willing to wash and stay on anode then galvanic corrosion is a fact of life. Of course ... if you only use your boat in distilled water then you will never have a problem.
 
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henryo

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Re: 1996 Force 120 Trim Pump help

OK got the trim motor off.

Steps taken were:
1. remove the 4 bolts from the top of the existing trim motor.
2. pull the motor off the resevoir.
3. remove the front two bolts
4. remove the rear left bolt
5. at this point I got lucky and the casing of the resevoir broke leaving the last remaining bolt intact.
6. got out the rotozip and ground down the aluminum frame that extended over the remaining bolt.
7. remove the last bolt.

So now I got the old one off and I installed the new one with no issues except one. Here is the kicker the existing unit was a three wire unit. The replacement unit is a two wire. Does anybody know if I can use the two wire unit????

Thanks
Dan

PS where there is a will there is a way!
 
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Mike2076

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Re: 1996 Force 120 Trim Pump help

Hello, i know what you are going through,in most cases i have just took the pump off and apart and cleaned it and they work fine,but back to getting it out the only way that i will do it anymore is to take it off the boat.it is heart breaking to be pulling out the last bolt and hear it snap!spray the bolts down with pb blast let it soak over night.if you do break a bolt the best way to get it out is to put a nut little bigger than the broke bolt over it and weld the inside of the nut to the top of the broke bolt,let it cool about 2 min. and carfully work it back and forth and take it out.the reason i said all of that is because they will usually break,but take your time and u might not have the trouble.Good luck. Mike
 
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Mike2076

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Re: 1996 Force 120 Trim Pump help

sorry i was a little behind im glad it all worked out.
 
R

RRitt

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Messages
3,319
Re: 1996 Force 120 Trim Pump help

you have to add relays or put in a new switch. 3w motors have a common ground with one lead for "up" and another lead for "down". 2w motor do not have a ground. They completely reverse wiring to change direction.
 
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Mike2076

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Re: 1996 Force 120 Trim Pump help

give me a day or two and i will find out exactly what u have to do.Mike
 
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