88' Force 85hp Power trim unit seems weak going up after replacing.

[DunbarLtd]

88' Force 85hp with power trim and tilt unit

Recently replaced power trim unit and valve. Added proper oil (30w non detergent) as instructed from dealer.

At first it was very slow going up. So i kept trying and eventually it started to go up and down. I figured since the system was empty it had to get distributed and so after a couple up and downs and adding more oil it started to work ok. Then it sat overnight and when i tried it in the morning in wouldnt raise up without a little assistance. So i cracked the cap and was able to add a little oil to bottom of fill hole. So we raised it up and down mayb 5-6 times and it finally started to work up on its own and it sounded strong and raised up like i thought it should. Let it sit overnight again and in the morning is began having same weak movement.

I noticed when it was struggling it made a high pitched whine but when it started to work properly the sound got deeper and just sounded stronger. Now of course this is raising(and lowering) past the slow zone. Not sure what to call that zone at the bottom where it moves really slowly after it makes contact with the main piston.

I took it out for a run on the lake today and it started to move up and down at the dock ok but it didnt seem like it was as strong as it was the night before. So when we were @ WOT it didnt seem like it wanted to work at all. Then finally got back to the dock and it was struggling again and needed help to raise.

Is there still air in the lines and is there a bleed procedure or is there possibly something else going on? I am not too familiar how to troubleshoot these hydraulic systems.

Also when i cracked the fill hole screw every time a little air would hiss out like it was pressurized. Not sure if this is normal or not.

Thanks,

James

 

[jerryjerry05]

Where did you buy the unit?
You buy just the pump or the complete set?
Where was it made?
​Sounds like the dreaded Chinese junk???

Are all the connections good?
​The lead to the relays in good shape?
The brushes in the electric motor in right?

Your T@T unit is a 2 stage unit.
The "slow" is where the initial trim is done.
Then the "fast" is for tilting out of the water.

​You should be able to trim under load but tilting is a bit harder when moving.
It can be done but you can damage the unit.

A guy on e-bay rebuilds them.
​The original unit even rebuilt is far superior to any Chinese replacement.
152303544130 e-bay #

 

[DunbarLtd]

Well I ordered it online and it matched the part number but i noticed the reservoir isnt as tall as the original. And yes it was made in taiwan. I bought the pump(resevoir and motor) and the valve body. I believe both are brand new. It didnt state it was re-manufactured.

I still have the old unit on my shelf. Maybe I can use the new valve body and swap it onto the old unit, When i purchased the boat the trim worked pretty good but the reservoir leaked oil. I believe it was leaking from the large valve body oring. When i took the old unit apart and removed the valve body i actually found sand granules in the bottom of the valve. How that happened i have no idea. But even with that junk in there the trim was working. So i purchased a new valve which was exactly the same as the original one as far as design. I am an electrician by trade so yes all connections are good. I will check the lead to the relays again to make sure.

Also so the air hissing out is normal? Thats what struck me as odd the most.

And i didnt open the motor up on the reservoir. It came enclosed and sealed and i just wired it up to the relays. I only installed the valve onto the reservoir with the four allen head bolts and added thread lock to all the fittings going into the valve.

And I didnt know trim was only supposed to work at that slow zone(stage 1). I was obviously trying to TILT the motor when underway. Good to know.

Oh and i bought the valve body from this company:

http://www.maxrules.com/fixforcetrim.html

The resevoir and motor was off ebay.

 

[jerryjerry05]

Maxrules usually pretty good about their products and helping with them.
Post pics of the new stuff?

 

[SkiDad]

that valve body at maxrules that is a good one. I believe it's the ones made in Florida. The air sound is not normal - the reservoir is not supposed to be pressurized. it's just for hold oil difference when the rams are retracted. I would try the old pump like you said.

 

[DunbarLtd]

Yes thats the outfit out of Florida. The valve didnt have a country name on it but im quite confident its a solid product. So I will swap out the valve and use the old reservoir/motor which should be just fine.

Last question. I may have done an improper fill procedure and caused the trapped air myself. I was filling the reservoir when the motor was down, cycling up and down couple times - then refilling when it came back down. I then read you should fill it when it is UP and crack the fill hole plug to allow air to escape while cycling up and down. Is this correct???

Do you know the correct fill procedure for this trim/tilt setup? Also can i get air out of the system by cracking the main trim piston/cylinder fitting as the motor is coming down and quickly close the fitting? Or will this not do anything? And then do the same for the tilt cylinder? Crack the fitting, let if fall and then tighten when i think air is escaped?

Thanks

James

 

[SkiDad]

I'm not sure if up or down when filling - I've done 2 engines and did them both when down - it will bleed itself if you run it up and down 4 or 5 times. Just add some more oil when you bleed it b/c it will need more.

 

[Mohawkmtrs]

Check and fill the reservoir with the motor UP.

Ski Dad is right...it bleeds itself after 5-6 times.

 

[jerryjerry05]

You do NOT fill while it's in the up position.
Filling while it's up is bad info.
You'll push oil up into the electric motor and it'll be another problem.

 

[DunbarLtd]

Thanks Jerry. Since the reservoir fills when its lowered, filling it while it is up didnt sound right to me either. But i wanted to check first to make sure.

But when i looked into the bottom of the reservoir it seems there is a rubber bushing/seal/oring around the shaft of the motor. Doesnt this seal keep oil from entering the motor?

And in the seloc manual it says to have the motor in full tilt up or down when filling.. as long as its all the way to its travel.

Edit: I just found the part in Seloc for bleeding and it says to have the motor UP when checking or adding fluid. And I was wrong in that the fluid is at it HIGHEST level when the motor is in the UP position and the piston is fully extended.

You seem to disagree with this?

 

[jerryjerry05]

The "seal" is for normal operation to keep the oil from pushing up into the electric motor.
​The pressure you'd generate if you added the oil while up is huge.
It can blow right by that seal.
​It has enough pressure to tear your skin.

​From 3 manuals.

THE BOOK SAYS!!!!!

​The unit should be FULLY RETRACTED to add oil.
​Fully retracted is down.

​You can do it either way but my way won't cost you an electric motor.

Seloc is god reading material if you have an outside toilet and run out of toilet paper.
Clymer isn't any better.

Buy factory manuals, I do.

​While your working and getting it right, maybe rebuild the old pump and keep it as a spare??
​

 

[jerryjerry05]

Further research there are 2 types of reservoirs for the earlier Forces(86 and older)
And 87 and up.
​The reservoirs have different capacities.
​The older didn't need as much oil to operate the system.
The older units used 20w or 30w Non detergent.
The newer 10-40

 

[DunbarLtd]

No Title

Im being lazy now and didnt take a picture but this is the exact same system i have except mine is black. I believe they are the Prestolite systems. It takes 30w non detergent motor oil. And yes the fill hole is pretty low on the reservoir as you can see so not much is needed.

I got it to work last night. In the manual i have i followed the bleed procedure. It says to check the fluid level when the engine is up and then to cycle the motor up and down with the fill plug removed. The first couples times it needed some help going up. After 3-4x it started to lift on its own. While it was up and the cap still removed we let it sit for 10 minutes each time. Not sure if this made a difference though. the thinking being it allowed any extra air to escape.

Also i called a local marine mechanic and he said he fills the systems when the engine is UP. Interesting to get different opinions on this. He said he isnt worried to much about air in the system as it simply compresses in the void in the reservoir and is harmless. His concern is if there is enough fluid. But i think i got it working. I will check again later today and see if it still works.

 

[jerryjerry05]

Being as that ones white and yours is blue.
They are 2 different outfits.See last post
​White has a different reservoir and the electrics are different.

If you leave the cap off it can't build up pressure but it can shoot oil if your not careful.

If filled while it's down you'll never have to worry about over pressurizing.

 

[DunbarLtd]

OK I tried it this morning and no go. Last night we had it going up and down on its own. The trim works perfectly. When it gets to the tilt is struggles and basically goes nowhere. Im assuming the tilt cylinder o-rings are shot? Its a brand new valve body so i doubt its that. But the fact we got it working is odd, because if the tilt cylinder was bad i would think i couldnt get it to work at all? Any thoughts???

 

[Jiggz]

Have you done a leak down test? If not you should so you can figure out which component is leaking by. Tilt the motor all the way up and let it sit for awhile. Does it come down on its own? If it does, then do the leak down test to isolate which component is leaking down. If it does not come down then you know the problem is with the valve body or pump unit. Do the test and let us know.

 

[DunbarLtd]

Ok I have her up as we speak. Ill check tomorrow morning. And i just wanted to say how much i appreciate this help. You guys are spending your free time helping me and i cant say thank you enough. Without your advice id be completely lost and most likely be emptying my wallet into the mechanics pockets. So again thanks and ill come back with the results in the morning.

 

[DunbarLtd]

OK its been over 3 hours now and the motor hasnt dropped a single mm.

Also I made a mistake and thought i bought the new valve body from maxrules but now that i remembered and found my receipt i bought it from db electrical and it was off Amazon. I do not know about that company and if it is the cheap chinese version or not. I believe this may be my problem it appears since the motor has not dropped

. There is a 1 year warranty thankfully and ive only had it for a few months. I know it is not the motor because i tried both a new motor i bought and the old motor and the same issue arises. Which is I can get it working but then over night it wont tilt up. Trim works fine though.

But it is NOT dropping while motor is all the way up. I will wait until morning just to make sure.

 

[SkiDad]

the db electrical are the chinese versions.

 

[DunbarLtd]

Well it figures. I should have known because of the price difference. Ill be shipping it back this week for sure. And then hopefully I can rebuild the original. Ive read myself to death on all the threads on here about rebuilding them. RRitt (sad that he passed RIP) had some excellent posts about the issue so I guess its back to the drawing board. .

And out of curiosity, any idea what the issue is with those chinese ones? It seems to me like a valve inside is getting stuck perhaps but maybe someone can chime in whos dealt with these cheapies before.