'06 90 Yamaha 4-stroke - another power trim help request

[Tiger-Striped-Bass]

Power trim motor wouldn't turn the other day on my '06 4-stroke 90 Yamaha. Solenoid would click and power was going out to the trim motor but it would not spin. Used the manual bypass to raise/lower motor. Got home and I took the motor off of the pump (engine fully lifted up). The reservoir at this point is full, and is even a little above the fill tap. No part of the pump or lines were exposed to air. The fluid level stays right below the seam where the motor mates to the pump assy.

Inside the motor I find a lot of black dust from normal brush wear. I clean that out and brighten up the surface of the armature where the brushes contact. Motor works just fine now. Re-coupled it to the pump and the motor runs fine, but the trim doesn't move the hydraulic cylinder/engine.

At this point, I start to wonder if air did somehow get in the system, though I can't figure out how. Further, the motor will hold any position with the bypass closed and will never bleed down. It seems to me that if air were in the system, it would not hold position - you can't budge it either way with the bypass closed. I read here that these are self-bleeding systems, so I do as prescribed and cycle the motor up and down using the manual bypass (only way I can move it). However, if I crack the fill plug, I get fluid, no air. Remember the level when I removed the motor was above the fill tap. Apparently it stays there. So that procedure gets me nowhere. I took the motor back off just to verify the two are meshing together and the coupling is ok. All appears fine.

Obviously, I won't be able to vent air out of the fill tap if the fluid level is above it - I realize that. But remember, this thing has had that much fluid since it was created, so I don't want to drain any, in an attempt to bleed air that may not even exist. I am trying to make the least amount of changes from when it did work to prevent introducing new problems. I guess the way around that would be to cycle it up and down as before, but bleed any air by cracking the motor from the pump.

I just really can't see how I could have gotten air in the system and I can't see how the cylinder would hold that heavy motor up, if there was air in the system.

You guys have any suggestions?

TIA

 

[pine island fred]

Re: '06 90 Yamaha 4-stroke - another power trim help request

You did get air in the system. You can first try to cycle the pump with the bypass valve slightly cracked. Am happy to hear you got that valve to open, some can be a bear and require light hits with an impact wrench. Anyway, You might have to help the motor along by standing on the leg or prying it up with a 2X4 while running the pump. Do this with the fill cap on tight. Reservoir is full with the motor tilted full up. Are the trim pistons fully retracted? You might have to give them a tug with vice grips to get things moving.
If the pump motor screws up again, go to SIERRA ONLINE OUTBOARD PARTS CATALOG. Motors are pretty reasonable there, just bought one myself. FRED

 

[pine island fred]

Re: '06 90 Yamaha 4-stroke - another power trim help request

This is directly from the YAMAHA manual. Motor down, fully open the by-pass valve. Manually raise the motor and let it fall under its own weight. Close the by-pass valve and wait 5 mins. Raise the motor with the pump and let sit for 5 mins. Remove the fill cap and top off with fluid. Repeat 2 or 3 times.
On pump motor replacement, book says to fill the pump area with fluid and turn pump drive with a screwdriver to remove air from between the gear teeth. That would be with the unit on a bench. FRED

 

[Tiger-Striped-Bass]

Re: '06 90 Yamaha 4-stroke - another power trim help request

This is directly from the YAMAHA manual. Motor down, fully open the by-pass valve. Manually raise the motor and let it fall under its own weight. Close the by-pass valve and wait 5 mins. Raise the motor with the pump and let sit for 5 mins. Remove the fill cap and top off with fluid. Repeat 2 or 3 times.
On pump motor replacement, book says to fill the pump area with fluid and turn pump drive with a screwdriver to remove air from between the gear teeth. That would be with the unit on a bench. FRED

Thanks for the advice Fred, I really appreciate it. I have tried just what you describe from the manual. No luck.

Am I understanding correctly that after the first manual rise/fall, I should be able to raise the motor with the pump? Or am I running the pump as I manually raise the motor with the bypass? I guess it really doesn't matter, I've tried both ways and the result is the same. No movement.

 

[Tiger-Striped-Bass]

Re: '06 90 Yamaha 4-stroke - another power trim help request

Fred, is there anythig about the bypass valve positioning? Is it only open/close or is there some inbetween position. From 100% closed tight, there is probably close to 1 full turn before it releases. What is the normal, in-operation position? Is it 100% closed tight, or something less, between that and release?

 

[Tiger-Striped-Bass]

Re: '06 90 Yamaha 4-stroke - another power trim help request

I still don't think it's air. No part of the system was ever exposed to air. Everything has always been submerged in fluid. Until someone can explain to me how air can get below a fluid level, I'm just not buying it. Further every method of bleeding air out of a system does nothing, probably because there is none.

 

[pine island fred]

Re: '06 90 Yamaha 4-stroke - another power trim help request

This is a bit strange, pump should prime eventually. I had a very hard time with my by-pass valve, had to use an impact setting on my drill to open it up. When I put it back together, I left the screw at what I thought was tight but not over tight. Ran into the same problem you are having and had to really torque that screw down.
Then I had to do the pushing and lifting of the piston, was not connected yet, to give the SOB the idea of how it was supposed to work. Initally had to push the piston down with a 2X4. Once it got the message, I had to fill the reservoir a few times as it was full of bubbles. Thats a small hole, are you sure you are getting fluid in there? I had lost more fluid than I thought. Are you sure the drive pin did not fall out when you reinstalled the motor? You really did not touch that much, the thing should work.
Suggest you go to yamahaoutboardparts.com and see if RODBOLT can help you out. FRED

 

[Tiger-Striped-Bass]

Re: '06 90 Yamaha 4-stroke - another power trim help request

I'm done. Added a little fluid and the pressure busted the intermediate piece between the motor and pump. That's a $350 part. Ordered a whole motor assembly for $500.

Should have just taken it in.

 

[pine island fred]

Re: '06 90 Yamaha 4-stroke - another power trim help request

BOY, thats disappointing! Is there any chance you can stop that order? If your motor is a 4 bolt mount, I can FED EX one to you today. Just replaced mine and hung on to it to make sure that was the problem. Just found out that it is the relay that is intermittent so I have no use for a perfectly good motor.
Something is wrong. Is it possible that the motor was locked up originally from to much pressure in the pump? YAMAHA manual shows the pump body has 2 shuttle valves, 1 up relief valve, 1 down relief valve, 2 check valves. Manual does not impress me as there is no description / operation like other factory, MERCURY, books. Just exploded views and brief troubleshooting. Pump pressure is checked by removing the by-pass valve and installing a special fitting in there.
I know it is to late now but write down somewhere, sierra marine online parts catalog if you ever need more parts. My motor cost me $181, not trying to rub any salt there. Again, if it is a 4 bolt motor, try to cancel. BTW, I have gotten in trouble before trying to give things away so this post might not last. regards FRED

 

[Tiger-Striped-Bass]

Re: '06 90 Yamaha 4-stroke - another power trim help request

Fred, I was able to cancel the order. I do have a 4 bolt mount. But I don't really need the motor. I need the graphite piece between the motor and the pump. It is part number 6D8-43881-01-00 . It is #12 in this diagram described as the "end frame":

View attachment 101416
As far as Sierra, the parts listed for my motor did not include any power trim parts. I was able to find numerous other sites that had inexpensive aftermarket motors in the price range you describe, but the piece I need (end frame) did not come with their motors, as the entire OEM motor assembly does. That's why I went the route I did. I assume that you had to reuse your end frame if you bought an aftermarket motor? If so, you won't have the part I need. I ordered the whole assembly because I figured I would eventually need to change brushes or replace the motor, so it was cost effective to replace the whole assembly and have few a parts left over.

Let me know if you have the part I am describing. That would be a tremendous help.

 

[Tiger-Striped-Bass]

Re: '06 90 Yamaha 4-stroke - another power trim help request

correction - i have a 3 bolt motor. it's the end frame that it bolts to, that is 4 bolt. see diagram in previous post

 

[pine island fred]

Re: '06 90 Yamaha 4-stroke - another power trim help request

Found your motor on yamahaoutboardparts.com The part nbr. you list does not look like mine. Is strange that it would change over a few years, mine is an 05. That end plate is for sale there $367 where the whole motor goes for $570. Awful expensive hunk of plastic. My replacement motor came with the plastic base. Is nothing more than a thick spacer/ motor adaptor plate secured to the motor by 2 wimpy sheet metal type screws. FRED

 

[Tiger-Striped-Bass]

Re: '06 90 Yamaha 4-stroke - another power trim help request

Yeah I think my end frame has a bit more to it than your spacer.

I usually use L&M marine for OEM parts. They are in AL. I am in LA. End Frame is $318, whole motor assembly is $491. I only need the end frame, but I will have to go OEM to get it. So essentially, I can get an OEM motor for another $173 over the price of the end frame. Shipping is $26.


Hindsight 20/20, I should have left the bolts loose to allow excess to overflow out when I let the engine down. I didn't realize it wasn't metal with all of the blue paint on it. Since I didn't leave it loose, I guess if it hadn't wrecked the end frame, the pressure would have wrecked something else.

Hey thanks for the offer. I think I will just bite the bullet (my wife is going to hemorrhage) and re-order. I'll put it back together and bring it to the shop. Can't afford another mistake like that. Logical reasoning and thinking only goes so far, and falls short of practical experience and background knowledge the shop guys have.

You know what makes this even more hard to take? I used the boat on a Friday with no issues. Saturday, I found out a friend who had out of town family in for the weekend, couldn't get his boat to start. So I offered him mine. He told me the trim worked to get the transom saver off, but never did afterwards. He still took it out for a ride anyway, before he called me for help. That's when I found the motor dirty and cleaned it out and it worked fine. As for the rest of the problem, there's that nagging feeling that I don't know the whole story of what happened that day, that might explain all the trouble I've had. I'm pretty sure there's nothing more to the story and the same thing would have happened on my next trip, but there's that little nagging doubt, you know?

 

[Tiger-Striped-Bass]

Re: '06 90 Yamaha 4-stroke - another power trim help request

Hey, are you sure your's is different? All of the '05 F90 diagrams look the same as mine and have the same p/n's. The 2 strokes are different, but the 4's are the same.

 

[pine island fred]

Re: '06 90 Yamaha 4-stroke - another power trim help request

The one I have is 64E-43880-01-00. Wires go into the top of the can/ motor. Unless I was looking at the wrong print, looks like your wires enter at the base. Will do further research. I am going by the prints on yamahaoutboardparts.com FRED

 

[pine island fred]

Re: '06 90 Yamaha 4-stroke - another power trim help request

Went back and checked again, they are different. Mine is an 05 F115. Since they are basically the same motor I assumed a simple pump motor would be the same. The SIERRA motor I bought fit a bunch of years and HP. You would not think things would have changed that much. regards FRED

 

[Tiger-Striped-Bass]

Re: '06 90 Yamaha 4-stroke - another power trim help request

Ok Thanks for trying.