Yamaha G2 Running Erratically

[timquagliata]

Originally Posted by CP241

Your belt has definitely seen better days.

Can you take a video of the cart in neutral and rev the engine so we can see thr clutch operation?

Your belt is shot for sure. But before replacing the belt it's best to watch both clutches work to verify they transition smoothly between each other

OK. I likely have a pretty dumb question. How do I put it in Neutral?

[CP241]

Ok, sorry... there isn't really a "neutral" but if the shifter is straight up/down between forward and reverse, it really isnt in gear either hence "neutral" :)

[timquagliata]

Originally Posted by CP241

Ok, sorry... there isn't really a "neutral" but if the shifter is straight up/down between forward and reverse, it really isnt in gear either hence "neutral" :)

Here is a link to a video. Let me know if you want me to rev it more.

https://streamable.com/05e5v

[CP241]

Good info there, couple things.

First, your secondary clutch isn't doing jack squat. It should spread open when the motor revs up.

Second, pull the cover off of the primary clutch. It sounds like you may have a broken flyweight in there (big clink/clunk when you start or stop the motor). I'd bet there's a dent in the gold cover above that weight, if not a small crack. If there isnt, you caught it early because there will be.

[timquagliata]

Originally Posted by CP241

Good info there, couple things.

First, your secondary clutch isn't doing jack squat. It should spread open when the motor revs up.

Second, pull the cover off of the primary clutch. It sounds like you may have a broken flyweight in there (big clink/clunk when you start or stop the motor). I'd bet there's a dent in the gold cover above that weight, if not a small crack. If there isnt, you caught it early because there will be.

OK, so I should go ahead and replace the secondary clutch. Do you think this is the cause of my original issue?

I'll remove the cover on the primary clutch and inspect for a broken flyweight. If there is a broken flyweight, is this something that can be fixed, or will I need to get a new primary clutch too.

Also, should I be changing my gearbox oil regularly? Also, how do you change the gearbox oil?

Thanks for all your help

[CP241]

I've got a clutch with a broken flyweight, I'll send a picture later. You can order flyweight kits to rebuild the clutch, these are a good alternative to replacing the clutch if the sheaves are not worn. If the sheaves (part where the belt rides) are wavy or grooved, then just replace the clutch.

On the trans, there's a drain plug on the bottom, and a level plug in the middle, and a big air vent at the top. Remove all 3 of them and let it drain. Then reinstall the drain plug and fill it through the air vent in the top until oil starts to run out of the level indicator plug in the middle. Reinstall the 10mm bolt in the level indicator plug and replace the air vent. pretty easy

I'll get a picture of that for you too when I go outside.

And yes, between the worn belt and the messed up secondary clutch, I think that's whats causing you to hit the rev limiter. The engine is trying to speed up, but since the secondary clutch isn't working right it's stuck in "low gear" so it never goes fast enough for the flyweights in the governor in the transmission to spin enough to back off the throttle.

The governor and rev limiter are 2 separate things, but they work together. The rev limiter just keeps the engine from revving too high and causing damage. The governor spins inside the transmission and is set based on speed of the transmission/cart. This directly pulls on the throttle to maintain the preset maximum speed that it is set to, which is why when you drive them it will accelerate, get to speed, and then you can hear the engine speed increase/decrease as necessary to maintain that constant speed. The rev limiter is only there to protect the engine in case the governor cannot do its job.


If this cart has been sitting for a while, I would remove the secondary clutch before ordering a new one. It may just be something jammed, broken spring, or something else that's causing it to not work like it should. Remove it, inspect it, and then determine if it needs to be replaced or not. I'd take a rebuilt OEM clutch over a brand new aftermarket one any day.

[timquagliata]

Originally Posted by CP241

I've got a clutch with a broken flyweight, I'll send a picture later. You can order flyweight kits to rebuild the clutch, these are a good alternative to replacing the clutch if the sheaves are not worn. If the sheaves (part where the belt rides) are wavy or grooved, then just replace the clutch.

On the trans, there's a drain plug on the bottom, and a level plug in the middle, and a big air vent at the top. Remove all 3 of them and let it drain. Then reinstall the drain plug and fill it through the air vent in the top until oil starts to run out of the level indicator plug in the middle. Reinstall the 10mm bolt in the level indicator plug and replace the air vent. pretty easy

I'll get a picture of that for you too when I go outside.

And yes, between the worn belt and the messed up secondary clutch, I think that's whats causing you to hit the rev limiter. The engine is trying to speed up, but since the secondary clutch isn't working right it's stuck in "low gear" so it never goes fast enough for the flyweights in the governor in the transmission to spin enough to back off the throttle.

The governor and rev limiter are 2 separate things, but they work together. The rev limiter just keeps the engine from revving too high and causing damage. The governor spins inside the transmission and is set based on speed of the transmission/cart. This directly pulls on the throttle to maintain the preset maximum speed that it is set to, which is why when you drive them it will accelerate, get to speed, and then you can hear the engine speed increase/decrease as necessary to maintain that constant speed. The rev limiter is only there to protect the engine in case the governor cannot do its job.


If this cart has been sitting for a while, I would remove the secondary clutch before ordering a new one. It may just be something jammed, broken spring, or something else that's causing it to not work like it should. Remove it, inspect it, and then determine if it needs to be replaced or not. I'd take a rebuilt OEM clutch over a brand new aftermarket one any day.

I removed the primary clutch and two of the three flyweights are broke. Also, you are correct the cover is cracked. I'll likely just replace the primary clutch. Any suggestions on how to remove the other sheave as seen in my blurry picture? That thing won't budge.

I tried to remove the secondary clutch with no luck. Any suggestions on how to pull it off? I'm not sure there is enough room to use a puller.

[CP241]

Thought I heard the primary dinging... sheaves look pretty wavy, I'd replace it. You will need a puller tool to remove the rear fixed sheave. Dont try to do it without one you'll never get it off!

The secondary shouldnt be too horrible. Try this https://www.google.com/url?sa=t&sour...QUTkXi2GY91VgX

I use a harmonic balancer puller.

[slonomo]

Wow I've never seen a primary clutch that bad. What would cause that? Extreme wear?

[CP241]

Originally Posted by slonomo

Wow I've never seen a primary clutch that bad. What would cause that? Extreme wear?

Looking at the perfect line of green in picture 4, I think this cart spent some time in a flood zone...

Tim,
Knowing that you've got 2 broken fly weights on the primary clutch, replace that first before ordering a new secondary. Looking at the wear pattern on the primary, there's a really good chance the flyweights were binding on the cover (hence the cracks) and not even allowing the secondary to have a chance at spreading open. It may be ok.

Still wouldn't hurt to pull it, clean it and inspect it. But your secondary clutch may be okay after all.