Yamaha F90 Tilt/Trim Diagnostic and Motor replacement

While not having functional trim isn't going to leave you stranded (unless it only trims up, been there done that)
It is awful nice to be able to adjust the attitude of your outboard to optimize for the load, speed and conditions you're boating in.
Where do you go when ones trim stops working?
I have the answer, on this Yamaha F90TLR, it was the trim motor, but I point out the fuse, and how to test if the solenoid pack is working, While other brands of outboard may be slightly different, it is a similar concept as to locating relays/solenoids and fuses and testing to see if there is a fault with any of that mess.
Once we diagnose it is indeed the trim motor to blame, you'll get to see what removing it entails, as well as how they have changed and what parts you need to replace in order to be trimming and tilting wherever you please!
2006 and newer Yamahas should all basically be the same exact setup as far as wiring and replacement process, 75-90hp use this motor, which can have part numbers 6D8-43880-00-00, 6D8-43880-01; 6D8-43880-09-00 or Arco 6258
Other HP ratings use different motors.
Links to the products used in this video:
➡Tilt/Trim Motor: amzn.to/35K29IG
➡Hex socket set: amzn.to/38LEFF6
➡Multimeter: amzn.to/3ifw297
➡Socket set: amzn.to/2LXaKkd
(These may be affiliate links which earn me a commission if you choose to purchase from one)

[@trythistv]

Links to the products used in this video: Tilt/Trim Motor: amzn.to/35K29IG Hex socket set: amzn.to/38LEFF6 Multimeter: amzn.to/3ifw297 Socket set: amzn.to/2LXaKkd (These may be affiliate links which earn me a commission if you choose to purchase from one)

[@kalaheo12]

I can't thank you enough, this was my exact problem too. The local dealership wanted almost $300 in labor, I got this job done from start to finish in 45 minutes thanks to you.

[@trythistv]

Awesome! So glad it helped you out, now get out on the water and enjoy yourself!

[@toddhooten]

This was perf. Easy to understand and it's just what I needed to go back fishing. Thanks

[@trythistv]

Awesome! Glad it helped you get back on the water!

[@MrHubris1]

My problem exactly! Thanks so much for the help. I figured out it had to be the motor, and you just confirmed it for me showing me what to do to fix it. 👍

[@trythistv]

Awesome! Glad the video helped, I've seen the relays (solenoids?) go bad but it does seem like these motors tend to wear out, they're in the water most of the time, I'm sure that doesn't do them any good, at least it isn't awful to fix

[@kennethblanchard6152]

Thanks for the incredibly complete video and explanation of the troubleshooting and replacement of the trim/tilt motor. I'm having to very lightly tap on the motor housing to get mine to work. The relays are fine.

[@trythistv]

Yup that sounds like your motor is on its way out. Glad the video helped you diagnose it, hopefully it helps you replace the motor as well!

[@auggie3952]

Thank you very much for this video. Very helpful. Explained perfectly. From lower Alabama.2024

[@trythistv]

Thanks very much! Glad it helped you out!

[@garybeard9071]

Excellent information and presentation.

[@trythistv]

Thank you! Glad it was useful for you!

[@hugoaguilar3740]

This is very helpful thank you and thanks to George

[@trythistv]

George greatly appreciates the compliment, he felt so fulfilled he decided to nap all day! Glad the video was helpful!

[@jimmylewis6070]

Awesome video! Instructions clear and percise! Thanks! I feel confident now and I'm ready to change my own motor. I'd like to add a hint if it's ok - To lube the motor's o-ring with a bit of the hydraulic fluid before putting it on the motor; makes it more workable & the oil will help expand the rubber making a lasting seal, as well as the life of the o-ring. Thanks again for the video! I'll be sure to check out more of your videos .

[@trythistv]

You're very welcome! And yes that is a great point on lubing the oring, certainly makes installation a lot easier!

[@jimmylewis6070]

@@trythistv I'd like to request how to install the trim/oil harness for the 90hp Yamaha. From motor to say, the digital multifunction gauge? Thanks.

[@armindaniel5555]

Thank you so much🙌

[@onecoolcamaro]

Great instructions!! Thank you so much!!!

[@trythistv]

You're very welcome, glad it helped!

[@olyeric61]

Thank you!

[@mikefowler1313]

Very helpful video

[@trythistv]

Glad it was helpful!

[@sgtz113ang]

thanks George ! hope i can fix my 70 and get it....purrring.....Zeke NC

[@trythistv]

George appreciates your comment by way of a yawn and stretch, hopefully you can get your outboard fixed!

[@TimsWorkshopTJY]

very good, mine is a big more messed up. My motor runs good hooked up to a 12v battery but not when the wire connectors are hooked back up to the switch wires and relays. when pushing the switch up and down on the motor the relays click. mine is a merc with one relay for the up and the other relay for the down. My next move is to disconnect the red lead from the soleniod and hook up direct to the battery to see if that is the issue. I'm also cleaning up all connectors with new heat shrink barrel connectors. I bought 2 new relays but didn't fix the issue so on I go. wish me luck

[@trythistv]

Since you already traded the relays that rules out the most common problem I see on the mercs, I see the solenoids go bad all the time on the alpha style sterndrive trim pumps, but idk if you've got an outboard if that would be the same or not.

[@cfauvel]

do you have a video of removing the whole assembly?

[@subasurfcasters]

Great video man. I have a yamaha f90tlr that i am having the problem of the trim just clicking both ways i can tap on the cylinder and it starts working again. Can you add tilt trim fluid to it or do you think its the motor. I didnt see a bolt to remove on the cylinder side to add fluid but there is a bolt on the motor side under where you remove the screws to remove the motor. Mine looks identical to the on in your video the motor cylinder set up. Thanks

[@trythistv]

Usually there is a small reservoir type thing that has a plastic plug to add fluid, but if you can't hear the motor run when you hit the button, and tapping on it makes it start running then your issue is almost certainly the motor is failing.

[@Marlin365]

Great detailed troubleshooting, thanks! My 2006 Yamaha 250 trim tilt stopped working yesterday with this heavy engine in the down position in the water.The relay is making the clicking sound on both up and down. I can't trailer it out on the ramp because the skeg would hit. I am getting 12V to the red terminal on the relay, and touched the blue wire to the red, but the engine didn't raise. So I think it's the trim tilt motor, agree? I will have to get close to the ramp, get in the water, loosen that screw to reduce hydraulic pressure, and somehow lift the engine up. Any other ideas on to get the boat out of the water, or other troubleshooting before I have to replace the trim tilt motor? Thanks!

[@trythistv]

I believe it was Red Green that said you need either a dumb friend or a son, and I don't have either, so I have to do it myself. Get a strong buddy and go wading on the ramp, or a ratchet strap and another boat and lift from the deck of it.

[@Marlin365]

@@trythistv I used the tried and true technique, and tapped the trim motor with a wrench. Somehow it worked, and tilt goes up and down now. So i just hauled the boat, and now going to follow your instructions to replace the tilt motor on 2006 Yamaha 250. Problem I can see off the bat is that third bolt looks like it's really hard to get to!

[@weedium]

Thank you! Time to replace a trim motor😑. My motor is all the way down, thank goodness they have a screw I can turn🥵

[@trythistv]

As red green says you need a dumb friend or a son for that part. Lifting the motor by hand is not easy 😂 hope the motor replacement goes well!

[@weedium]

@@trythistv Ratchet straps pulled the motor up for me. The best part was the brushes in the DC motor were stuck in place, filed them and works like new!

[@trythistv]

The best possible result! No sense spending money on something that just needed a little cleaning up!

[@tyyoung3698]

Any wisdom on effective ways to remove a stuck upper shockmount pin ? Engine's a '91 200TXRP. I've tried penetrating oil and picking the remains of the rusted circlip out, so far. Asking because on this engine, there looks to be zero room in which to place even a flex extension in order to get third 10mm bolt holding the tilt/trim motor.

[@trythistv]

I'd hate to have to try it, but heat. I've fought to remove stuck, rusty things a lot recently, and heat is the only thing that worked. you could try sneaking in with a 10mm on a 1/4 inch ratchet, its been incredibly tight on every one I've done, but it did fit just enough to get it off and back on.

[@hamrnguns]

George I have a 1999 70 HP Yamaha. The power trim works great but once the motor gets down to the trim rams it doesn’t go all the way down. I took it to a mechanic and he replaced all the seals and rings and I filled and bled the air. I think I got all the air out. What’s your thoughts?

[@trythistv]

I would look for something obstructing it, going down should be the easy part, going up is where you'd have issues from seals or air. You could try loosening the relief valve on the side and seeing if it goes down all the way.

[@hamrnguns]

@@trythistv when I release the release valve it does go down all the way. That’s why I’m puzzled. I don’t think I can leave the valve slightly opened all the time though. Wouldn’t that allow air into the system?

[@trythistv]

The bypass valve is an internal bypass, so you could theoretically leave it cracked open and it wouldn't let any air in, but your trim will always sink down to the bottom slowly that way. When it stops going down does the pitch of the motor change like it's got an air bubble in there or something?

[@hamrnguns]

I got it fixed. As it turns out there are two ways you have to bleed the system. One is for the tilt and the other is for the trim. The trim needs to be bled with the manual release valve. I got ahold of the owners manual. It’s in there.

[@erc2fla]

Mine has been clicking with no movement, but with a small tap on the reservoir it works

[@trythistv]

That pretty much tells you it's time for a motor, just like what I did in the video.

[@grantsaari1629]

My motor blows a fuse when I press down only and goes up fine. Is it a safe guess that the down relay is bad?

[@trythistv]

Sorry I missed your comment somehow. It is possible than something is wired up wrong for it to blow a fuse, but also incredibly likely that the relay has just failed internally.

[@ian_83]

Very helpfull. But does anybody know how we disassembly the piston?? It has a loss of fluid from the upper seal ring. I could unscrew the the upper screw (trim cylinder end), but i cannot pul out the piston....

[@trythistv]

Typically the piston will come out after the end cap has been removed. However remember the seal on the piston is meant to hold hundreds of not thousands of psi so you will unlikely be able to remove it by hand. You may be able to slowly pull it out with the bypass screw loosened, or you can set a drain pan down, push the trim up button and stand clear and it'll self-disassemble

[@ian_83]

@@trythistv thank you very much for your response. I opened it, and could change the seal. But the problem now is that the trim is workind (goes up for 5 cm) but the tilt isn't..

[@countdooku1971]

Where is a good place to find a replacement tilt/trim motor that doesn't cost an arm, a leg, and your firstborn child? My local Yamaha dealer wants $850 for that little bitty motor. Is there the possibility that the tilt/trim motor could be rebuilt for a reasonable price? Thanks!!

[@trythistv]

I've had good luck with API, Arco, and Sierra parts, you can find those brands online quite easily, and likely can cross reference from the yamaha part number for your specific outboard. Still not cheap, usually around $200-400, but thats a whole lot nicer than the dealer.

[@user-zh7yl2jh9m]

2008 yamaha 250 vmax hdpi vz250 When i push up or down on any of my trim switches my relay clicks motor does nothing up or down but can take either the green or blue wire off and touch it to the red wire on the relay and the motor will trim i have tried three different relays still didnt change anything what do u think the problem is

[@user-zh7yl2jh9m]

When i put a meter on the blue wire and the green wire it shows 0 even when u hit the switch up or down

[@trythistv]

@@user-zh7yl2jh9m If the relay clicks, but it doesn't trim yet you can touch blue or green to the red and it trims, then it has to be the relay, or something is wired wrong on the relay, take a look at this video kzbin.info/www/bejne/n2ndpIF6q7R7hac and see if your relay is wired up the same.

[@user-zh7yl2jh9m]

@@trythistv i put the factory back on it because it reads the same as both the aftermarket that i have tried and it worked before so i know its wired right

[@Labyrnthdom]

Mine clicks like this. But I can shake it or keep clicking up and down, and it will finally move. Once it has moved, it will work. However. Once it has sat for a few days. It clicks again. So im guessing my motor is starting to fail.

[@trythistv]

It does seem like that is the motor fairly often, I have seen it be the relays or connection to the relays. Saw one customers boat and the terminals on the relay were all corroded, we cleaned them up and put some dielectric grease to protect that from happening again and the trim has been working great since.

[@eccentricorgan]

Dwight Schrute

[@trythistv]

Bears, beets, battlestar galactica!

[@micahlaplante5477]

Ask George if I should buy a boat

[@trythistv]

George says MROWWW so take that as you see fit

[@mitsuturbo]

The stern and outboard look like they've been stuck in the mud for a long time.

[@trythistv]

It was just recently put on a lift to keep it out of the water, the lake scum tends to build up when they're left in the water a lot, we'll clean it off soon!

[@jimbobbojack9712]

Just hit a sandbar and trim and tilt stopped working on my old Yamaha I hope it's just the motor lol

[@trythistv]

I've also got a video about the cylinder seals in case they got damaged: kzbin.info/www/bejne/pYPIe3-Jm7GFp5o Hopefully it is a simple electrical fix though! Could be hitting the sandbar broke loose the wires or the seal on the motor and let some water into the motor. Let me know how it goes!

[@jimbobbojack9712]

@@trythistv cylinder seals were already leaking! Bought the wrong wrench to replace them and waiting for the correct to come in. Motor burned out in it. When I got home I tapped it with a wrench and it works...for now

[@trythistv]

Sounds like your projects go about like mine. Toss in a few backordered parts and it'd be real similar lol. Glad its working though, could be the impact jarred the brushes and one got stuck or something, Electrical things can be a little weird sometimes. If your motor does end up calling it quits for good at least you know how to replace it though!

[@jimbobbojack9712]

@@trythistv have to keep tapping it to get it to work I'm thinking it's time to replace. I found an Amazon special motor for $90 so we'll see how that goes. Couldn't fork over $390 for a new unit

[@trythistv]

@@jimbobbojack9712 I hear you on the cost, add boat or marine to the title of any part and the price triples. I have had good success with api marine parts, idk how great their price is though. But yeah having to tap on it sounds like it's time to replace it!

[@todorovz]

You are trying too hard with the cat. Just be yourself

[@trythistv]

I've always been very shy, and George is incredibly needy, half the time he interrupts whatever I'm doing if I don't include him, but yeah I need to work on delivery a bit. Thanks for the reminder, I'm trying!

[@madmanmechanic8847]

You have a very rare engine you have an out board with the rare factory WASP NEST SUPERCHARGER ! At 120 MPH the engine sucks in the WASP NEST and it boost the HP to over 550 net brake horse power . I have seen speeds of 200 MPH with the WASP NEST INDUCTION!

[@trythistv]

LOL! The weird spark/flame arrestor on this boat looks alarmingly like a wasp nest doesn't it? With the added power I think a prop change may be needed to take advantage of all that extra horsepower 😄

[@madmanmechanic8847]

@@trythistv All my years of working on boats I never seen an arrestor on a out board . Still looks like a wasp nest hahahahah