'87 Force 125 tilt and/or trim?

[RRitt]

Re: '87 Force 125 tilt and/or trim?

I'd stay away from ATF. Systems with ATF seem to break in the 13-17 year time frame wheras same system with oil breaks in 17-23 timeframe. Thickness of fluid does affect pressure and flow. But more importantly, if you use wrong fluid in a 2w system the backpressure gets ahead of motor torque and the system bucks when lowering.

 

[briguy2817]

Re: '87 Force 125 tilt and/or trim?

I'd stay away from ATF. Systems with ATF seem to break in the 13-17 year time frame wheras same system with oil breaks in 17-23 timeframe. Thickness of fluid does affect pressure and flow. But more importantly, if you use wrong fluid in a 2w system the backpressure gets ahead of motor torque and the system bucks when lowering.

Just an update for you. Took the valve body apart and replaced everything. Added the oil(20WT) and checked for bleed down. It still bled down from the tilt cylinder but was holding real good at the trim cylinder, no bleed down there. By the way, that weight oil is kind of hard to come by. I found some at a mom and pops parts store, with three inches of dust on it.

Took the tilt cylinder apart and replaced the two o-rings in there. Checked it for 3 hours and only drops about an inch in that time frame. I can live with that.

I may look for a slightly bigger o-ring to put in the tilt cylinder to see if that makes it hold even better. Depends on how long winter is going to be for me. All in all, not a terribly bad job to do if you have some knowledge of hydraulics, and how these things are put together. Thanks for your help.

Brian

 

[bjhc100]

Re: '87 Force 125 tilt and/or trim?

If I understand you:

Tilt /trim unit will raise and lower engine with engine shut off, in neutral or gear, and when engine is running, but only in neutal. Motor, pumps, and cylinders all working properly. This before you jumped it directly to the battery.

Also, once tilt/ trim unit has raised the engine, it is rock solid, even against a heavy load. All valves working ok.

Once the engine is placed in forward gear in any condition mentioned above, the tilt/trim unit rapidly lowers the engine all the way down.

Your tilt/trim motor has at least 3 wires connecting it to the wiring harness.

I can think of two things.

A Flow control valve is unseated allowing fluid to vacate the lifting cylinder. Coud be a check valve or a spool valve that is retracting to open position. I think these valves operate, by pilot pressure, and according to pumping direction. It may be that in gear your pump is switched to pump backwards with the fluid circlating in reverse. That would retract your engine in a hurry.

Second, I suspect some sort of ill working electrical interlock is at play. To be sure I would run continuity checks on wiring between the shift linkage mirco switches and pump to check for polarity changes in each shift position.

I think this problem has been with this boat for a long while. Dealers prepping new boats for sale have caused untold problems. I hope you solve it.

 

[Godfirst]

Re: '87 Force 125 tilt and/or trim?

Hi had a 88 force 125 outboard and just at it 20 year mark the center ram went out at the lake, I'll I can say it was a great motor but now have a 5.7 merc 260

 

[reelfishin]

Re: '87 Force 125 tilt and/or trim?

If I understand you:

Tilt /trim unit will raise and lower engine with engine shut off, in neutral or gear, and when engine is running, but only in neutal. Motor, pumps, and cylinders all working properly. This before you jumped it directly to the battery.

Also, once tilt/ trim unit has raised the engine, it is rock solid, even against a heavy load. All valves working ok.

Once the engine is placed in forward gear in any condition mentioned above, the tilt/trim unit rapidly lowers the engine all the way down.

Your tilt/trim motor has at least 3 wires connecting it to the wiring harness.

I can think of two things.

A Flow control valve is unseated allowing fluid to vacate the lifting cylinder. Coud be a check valve or a spool valve that is retracting to open position. I think these valves operate, by pilot pressure, and according to pumping direction. It may be that in gear your pump is switched to pump backwards with the fluid circlating in reverse. That would retract your engine in a hurry.

Second, I suspect some sort of ill working electrical interlock is at play. To be sure I would run continuity checks on wiring between the shift linkage mirco switches and pump to check for polarity changes in each shift position.

I think this problem has been with this boat for a long while. Dealers prepping new boats for sale have caused untold problems. I hope you solve it.

I solved it for now but it's snowing outside right now, it may just wait till spring now.
My impression is that there is an intentional interlock system, but that should have been eliminated when I direct wired a switch to the pump and battery. I cut the wire going to the rear of the trim ram, and the sensor wires are still on the pump and the tilt ram. And it seems to work fine, but I have no idea why, whether that wire has something to do with it or if the colder temps are the cause. I ran it in gear at full tilt on the ears the other night for about 20 minutes and it stayed up. With the pump wired direct the tilt and trim will work at all times, even allowing movement in reverse and neutral. If I leave it this way I'd have to be careful not to over trim or tilt the motor, you could easily 'trim' the motor right out of the water if you stayed on the switch. I think that's what the interlock was meant to prevent, or the fact that you can now tilt a spinning prop out of the water. That wasn't possible before. Before, if you started the motor fully tilted or trimmed, it would drop all the way down, (this wasn't possible due to a neutral safety switch though), but now it would stay put regardless of shifter location.
Maybe the sensor switches have something to do with it as well. I do notice that the trim gauge has about 7 wires going to it and with that red wire cut, it no longer works at all, no lights, nothing. I don't really care about the gauge or the buzzer, I can tell when its trimmed right without a gauge.
I've never had a boat before with a working trim gauge, why start now.
If I get a warmer day I'll wire the new switch in permanent to the dash with a couple of fuses in line too. The other wires are no longer needed as far as I see. I also think I'll rewire that micro switch to a new relay and use it only as a neutral safety switch, with no connection to the tilt and trim. I'd still like to know what or how that red wire causes the pressure to dump, unless they did put a solenoid in the trim ram. For now, so long as I can find a set of coils for this thing, I'll leave it where it is, if not, I still have it's replacement ready sitting in the garage.

 

[Captin Don Dada]

Re: '87 Force 125 tilt and/or trim?

Thank you for not giving up on this . I just bought a 87 capri cuddy with the force 125 two weeks ago. This is my first real boat other than a 12' john wit a 6 hp johnson . I have the same problem with the tilt n trim ive asked everyone n called what semed to be a million people and couldnt get solution or even the same sugestions . So thank you again for saving me from Banging my head to figure this out .

 

[clanton]

Re: '87 Force 125 tilt and/or trim?

I have pn for the check valve seals, after the valves are removed from the valve body, you have to take the valve apart, inside you will a needle that looks like a carbuator float needle. the seal goes on the end of the needle. O-rings that size are to small in dia. The seal can come from Merc or Briggs and Stration. I will have to look for the pns. these check valves hold the engine in position, if the other parts are working.

 

[RRitt]

Re: '87 Force 125 tilt and/or trim?

It's not really quite so simple. The aluminum tends to mushroom from back pressure on bigger engines. Need to pay attention to fit when taking apart and assembling. During disassembly take care not to wobble or rock the steel end cap when removing. if you do then it might further mushroom the aluminum check valve body. If the steel plug is not a really snug fit then corrective action should be taken. As with any delicate machine .... slow and methodical is the way to go.

 

[clanton]

Re: '87 Force 125 tilt and/or trim?

The Merc pn for the check valve seal is 820719, The Tecumseh pn is 631021, this number is a carb needle and seat seal, the seal is same as Merc, except color.

 

[reelfishin]

Re: '87 Force 125 tilt and/or trim?

Its been a while since I've been back to this post, I've actually sold the boat with the tilt/trim issue, but in the mean time, acquired another, the same year, with the exact same problems. The tilt unit is doing the very same thing. This one is on a motor only, which is now mounted on a motor stand, I scrapped the boat, which was too far gone in my opinion. The motor and it's control panel were removed as one since the boat was literally cut up.

The motor will drop to the fully trimmed position the instant it's put into gear.
It will however tilt and trim just fine while at rest either in Neutral or when not running. It stays up overnight, no pressure of fluid loss.
This motor is even cleaner looking than the first, it came from a 1988 Bayliner Trophy. It's a freshwater only motor, with no corrosion, and from what I could gather, very little run time. The boat was damaged beyond repair by a tree falling on the garage in which it was kept, the boat was crushed down to the trailer level across the bow.

The motor could pass for new cosmetically, has perfect 147 psi compression on all cylinders and runs as new.
I don't doubt there's a problem but what boggles my mind is that I have now had two with the exact same issue, and have seen two others doing the same.

I'll investigate this one further but for now it's just a spare motor.

 

[RRitt]

Re: '87 Force 125 tilt and/or trim?

the pump gives out in the 20 year time frame the rams can go 30 or more. No matter how pretty or ugly the paint is and no matter how much or little you used the engine ... it just doesn't matter ... the rubber gets old either way and the trim pump assy. still gives out around 20 years.

Using ATF or regular motor oil will cut some years off the valve body. Blocking engine up during storage may add a year or two. Saltwater will shave a few years off the motor and indoor storage may add a year or two. All of which expands the windows of failure to 17-23 years. So, to make long story short it is perfectly normal for a 20 year old system to bleed down and/or have motor problems.

BTW, I knew i had the part # somewhere. Correct part number for check valve is F17620. Don't lose the stainless retaining clip. they wholesale for over $1 each and you may need to buy a whole box just to get one. If you do lose it, then don't use steel and think it won't make much difference. If that ring gives out during use then you can kiss $300 goodbye.