Throttle Cable disconnected, hasn't seemed to run as well since.

Bought a 24' pontoon. Came with a 90TLR. Didn't get a huge amount of use before I got it.

First time I took it out it ran great. I wish I could have video of it but it felt much stronger. If my memory is right then it was hitting nearly 5500 RPMs on WOT. Ran 20 minutes across the bay and suddenly it came to a stop. About threw us off the front of the boat it gave out so quickly. We found that the throttle cable in the engine came loose, so we reconnected it and docked it. It seems to be connected properly.

The very next time I took it out, it felt weaker. If before the throttle went from a scale to 1-10 from idle to WOT, now I feel more like 0-8. The engine frequently dies at idle and has to be restarted. I have to give it some gas constantly. That and when I go WOT I only can get 4500 RPM now. I'm still new to this boat but I have video of us taking it the first time out and it sure looks like it goes faster. That and I remember how much we slowed down when the cable gave way, it was a huge change. Now at WOT I don't feel like it would stop hard like that because its going too slow.

Steps I've tried.

- Looked at the throttle cable, it doesn't look like it could connect any other way. The little switch can really go any further when I put it in WOT.
- Seafoam / Yamaha carb cleaner.
- Replaced Spark Plugs. All 3 seemed to be firing when we take them off one by one. All 3 old ones looked the same. Nothing significant that I know of.

Could the idle circuit on the carb be plugged? Maybe that's why it dies at idle? Wouldn't explain the lack of RPM unless that path also delivers fuel on WOT and now it can't?

I'm no mechanic btw. Don't claim to be either.

Oh also, before we put it in the water we also replaced the impeller.

When the throttle cable gave out I wasn't even touching it which is interesting to me. We just made it out of deeper water and I could see it was a bit shallower but I highly doubt we hit anything. Maybe sucked something up and its still there? Engine still spits out water but could it be partly clogged causing a lack of power?

I've flushed the engine with a hose after every use since I'm on saltwater. When connecting with that hose adapter is shoots the water through quite strong so that doesn't seem clogged at that point. Maybe clogged down lower?

(Forgive my ignorance, I'm learning)

schreck425 said:

Bought a 24' pontoon. Came with a 90TLR. Didn't get a huge amount of use before I got it.

First time I took it out it ran great. I wish I could have video of it but it felt much stronger. If my memory is right then it was hitting nearly 5500 RPMs on WOT. Ran 20 minutes across the bay and suddenly it came to a stop. About threw us off the front of the boat it gave out so quickly. We found that the throttle cable in the engine came loose, so we reconnected it and docked it. It seems to be connected properly.

The very next time I took it out, it felt weaker. If before the throttle went from a scale to 1-10 from idle to WOT, now I feel more like 0-8. The engine frequently dies at idle and has to be restarted. I have to give it some gas constantly. That and when I go WOT I only can get 4500 RPM now. I'm still new to this boat but I have video of us taking it the first time out and it sure looks like it goes faster. That and I remember how much we slowed down when the cable gave way, it was a huge change. Now at WOT I don't feel like it would stop hard like that because its going too slow.

Steps I've tried.

- Looked at the throttle cable, it doesn't look like it could connect any other way. The little switch can really go any further when I put it in WOT.
- Seafoam / Yamaha carb cleaner.
- Replaced Spark Plugs. All 3 seemed to be firing when we take them off one by one. All 3 old ones looked the same. Nothing significant that I know of.

Could the idle circuit on the carb be plugged? Maybe that's why it dies at idle? Wouldn't explain the lack of RPM unless that path also delivers fuel on WOT and now it can't?

I'm no mechanic btw. Don't claim to be either.

Click to expand...

What year is the engine? Being that the engine was running great as you mentioned prior to the throttle cable issue, my initial assessment is the throttle cable is still the issue. Rather, the installation of the throttle cable was not properly installed. The engine stalling while idling, coupled with the lack of throttle you're able to apply (rpms), suggests to me the throttle plates are closing when the throttle is in idle position. They should never be completely closed. This too points to improper installation of throttle cable.

Reply back with engine year/model number and we'll go from there.

ClassicAQ said:

What year is the engine? Being that the engine was running great as you mentioned prior to the throttle cable issue, my initial assessment is the throttle cable is still the issue. Rather, the installation of the throttle cable was not properly installed. The engine stalling while idling, coupled with the lack of throttle you're able to apply (rpms), suggests to me the throttle plates are closing when the throttle is in idle position. They should never be completely closed. This too points to improper installation of throttle cable.

Reply back with engine year/model number and we'll go from there.

Click to expand...

2002 Yamaha 90 TLRA.

If I had never felt the engine go faster than it does then I wouldn't have ever thought twice about this. But I'm pretty sure it did, that and the idle is running awful so that's why I'm not just thinking that it's fine.

Understood. But don't overlook the importance of the proper setting of the throttle cable and its effect on idle and WOT. They are directly related. Refer to your service manual for step by step procedures to ensure proper cable setting.

Ok. I'll look back into it when I can and let you know how it goes. I keep coming back to the throttle cable also because the carbs and other things were just serviced not too long ago and it ran for great for a good 30 minutes before the throttle arm became disconnected.

Quick question then, if the throttle cable isn't set right then when I'm at neutral its possible that its just not giving it enough gas to stay on? I guess I figured there'd always be a minimum amount of gas for neutral that it feeds it.

Thank you for the help!! To be continued!

schreck425 said:

Quick question then, if the throttle cable isn't set right then when I'm at neutral its possible that its just not giving it enough gas to stay on? I guess I figured there'd always be a minimum amount of gas for neutral that it feeds it.

Thank you for the help!! To be continued!

Click to expand...

Did the cable end with the circular eye detach from the magneto control lever? That's where I'm thinking it happened, since the inner diameter of that eye can become worn and thus not seat onto the control lever firm enough.

After reinstalling the cable, if the control lever on the engine was set retarded when making the connection then the throttle plates would be closed. This would indeed cause stalling at idle. There needs to be a small amount of air pulled into the carbs through plates at idle in order to keep engine running.

The picture below is of your engines control. The parts I referenced above is #6 and #7. And if this is the location where the cable detached, pay attention to part #9, the clip that secures cable to control lever.

So I had time to at least look at the cabling. I took photos, rotated them in photoshop to give you a good look at them, and this forum is having an error trying to upload them, hopefully they go through. Let me post this first to see if the pics work....

Awesome! Got them to go through! So the zoomed in photo shows where it came off. It's more on the bottom of the engine, not the top where the finally connection is made to rotate the fuel flow lever (sorry I don't know proper terms). Looking at your drawing, 6 and 7 look more at the top where it didn't disconnect. The bottom connection is where it came off and can't go any further, it runs into the gray stopper.

I guess if it is the levers, the one on top would have had to have shifted or something but it looks like it's going as far as it can go. That's why I don't believe we fixed it improperly and maybe something else is going on like fuel flow.

Btw, typically if I haven't driven it in a couple weeks I need to get starter fluid out to get it to start.

More pics hopefully attached.

Come on forum... you can do it...

One more...

I take it back, that actually might be 6/7

Since you had to jimi rig the end of the throttle cable to control lever, safe to assume the clip disengaged causing the cable joint to come off the control lever. I'd order that clip from a distributor. It's only a few bucks.

Now I think more about it, what I would do is time and sync the carbs after adjusting the throttle sensor control link. If you do not have the service manual for your engine you're in luck. I found one online for free. It's here: https://www.vansoutboardparts.com/s...-manuals/414-2002-yamaha-60x-70x-75x-90x/file

Section 3...Page 3-3 for carb sync and page 3-7 and 3-8 for throttle sensor control link adjustment.

Update: Never did figure out for sure what was going on. Finally trying to do something about it. We pulled the carbs to clean them and while disconnecting something we had to pull things apart. One thing we noticed was a lever that ran down under and to the other side to the oil pump. The connector onto the oil pump was split in half, part 6H1-41237-00-00. Didn't seem to notice anything major while cleaning the carbs. Sounds like if that level fails then the engine will be mixing oil on the heavy side which could explain it wanting to die at idle. The engine doesn't seem to smoke any though. We are installing a water separator, fixing that oil pump clip when we get a new one, and hopefully we'll be in better shape.

Live and learn man, it comes with being an amateur outboard mechanic. Not to be a jerk, but had you followed your service manual instructions for pulling and reistalling carbs you would have noticed the broken part. Assessing the oil pump is one of the steps involved with timing and syncing carbs. Be that as it may, like i said you live and learn.

I just meant that we hadn't tried anything since the last time that I asked in the fall, and we started the process, like you said to work on the carbs and did notice the broken part quickly. Thank you for the link of the manual. I've got a new part replacement, going to use the manual to sync the carbs, put it all back together and hope that fixes the problem.

Boat still has issues with the throttle cables.

Replaced the oil lever connecter, cleaned the carbs, but ran into an issue while putting things back together. The oil lever bar doesn't seem to stay free once we put the oil reservoir back in place. We tried to move hose lines around but didn't come up with a perfect solution. It doesn't seem like the connector we replaced, part 21 on the link, is free to move all of the way once we put the reservoir back in.

We put the boat back in the water and things are different now.

It idles great now. No more stalling. Seems to run stronger for the 0-50% throttle. I can wiggle the throttle and sometimes the engine wants to really go, as if that lever slips into position occasionally and things are correct for a second. I've had it want to take off fast while throttling down a few times. If I got past a threshold though, around 50%, it actually loses power. WOT gives me 3600 RPM but just the right spot around 50% Throttle can get me almost 4000 RPM.

Also, one time I throttled down and couldn't get the engine to idle for a bit. With the throttle in idle position it was acting like 25% throttle. I had to turn it off and when I'd turn it back on the engine would rev. Eventually I felt the lines slip back into place and it was back to normal. Definitely not good. Went into reverse pretty hard that time too.

Next time I get a chance we're going to look again to find a way to make that lever not get blocked when we put the oil reservoir back in... That sure seems to be the issue even more now. Anyone else have any insight that could help? Is this a known "gotcha" on engines?

http://www.marineengine.com/parts/yamaha-outboard-parts/2002/90/90TLRA/620302770006
Connector we replaced - Part 21
Oil Lever - Part 20.
Resevoir - Part 26

We still can't figure it out... We addressed that oil lever and made sure all of the lines are out of the way. Everything looks like it goes to the right position. Still, power feels fine until you get half way up the throttle, around 3100 RPM, and then the rest of the way nothing really changes even as the levers move. Now I'm starting to wonder if it's as simple as a fuel flow problem.

Could a failing fuel pump cause it to only provide so much fuel and then not any more fuel even though you're pushing the throttle further?