Manco Dingo Clutch smoking and won't move

[KrisMI]

Hello folks
I'm new to go karts. Just bought one for my son. It's 2002 Manco Dingo with Tecumseh OHH60 motor. It does have centrifugal clutch on it. It seems the seller put a new carburetor on it. The motor starts and sounds good when running but as soon as my son accelerates it barely moves and the clutch starts to smoke. I did some research first before I came here and read somewhere the motor RPM's have to be at least 1800 for the clutch to work properly. I think the carb needs adjustment because it doesn't sound like 1800 RPMs.
Now I'm looking at couple options. First is one that I saw online where some of you use like a belt torque converter. Should I replace the centrifugal converter with the belt driven TC ? If this is not possible should I get a predator engine and the TC? Or should I keep the centrifugal clutch and just adjust the carb and see what happens? Not sure which is better to have centrifugal clutch or belt driven clutch?

 

[JimD]

Rear tire looks to be bigger than 12" in diameter. If it is bigger than 12" get yourself the torque converter. I would be willing to bet it had a torque converter on it in the first place since the clutch you have now is a 10 tooth #41 sprocket. Manco bought 12 tooth #35 chain on the single seater inexpensive karts the #420 chain was used on the t/c karts.

 

[BaconBitRacing]

These Dingo's are tuff and fast karts. Get yourself a TC, and listen to anything JimD says, he's the owner of Max-Torque!

 

[KrisMI]

TC on the way.

 

[panchothedog]

Kris. Most 30 series torque converters which is what you need, have a plate that bolts to the side of the engine block. In your picture, the clutch hides the side of the engine.Maybe the Tecumseh is drilled and tapped like most modern clone engines are. If not, you might have to do some fabrication. If so, DON'T
despair. Once the torque converter is installed the kart will leave the line like rocket. Your son can floor the gas and if you were to stand behind it, you would not be able to hold it back. It will have that much power. As stated by JimD your rear tires are way too big for running a centrifugal clutch. BTW, nice kart, and welcome to the forum.

 

[Denny]

That kart from the factory came with a 30 series CVT on it. Just use a Genuine Comet Belt on it. Yes it’s more money now, but it will save you 10x down the road!

 

[Hellion]

Or, for more fun remove the cage, get some smaller wheels and tires and turn it into a parking lot racer. The root frame is the same as a Manco American Express...



Then you can use a clutch, just like Kurt Cobain in this pic.

I mean face it, it has no real suspension save for those springs on the front spindles and the back tires act as the rear suspension (bouncy balloon tires) so hilly, rough terrain can be kind of punishing. Just some options.

 

[Hellion]

Just for giggles, what is the current gear ratio on the kart?
Count the number of teeth on the clutch sprocket and the drive sprocket and divide.

Here's a site with an interactive gear ratio and speed calculator (near the top of the page) and more info on gear ratios:
https://www.gokartguide.com/gear-ratio-chart-speed-calculator/

The ideal ratio for a basic kart with 13-15" tires in the rear is something like 6:1, 5:1.

If the gearing is too "tall", the kart cannot launch and it will stall and smoke. Like putting your car in 5th or 6th gear at a stoplight and trying to go.

 

[KrisMI]

I know the clutch sprocket is 10 teeth. The cart is located on our property out of state so I will have to check the drive sprocket when I'm there on weekend. But since I'm new to this I didn't realize there is a speed lever on the motor itself. I did not touch it. Is this my be the reason ?

 

[Hellion]

.......But since I'm new to this I didn't realize there is a speed lever on the motor itself. I did not touch it. Is this my be the reason ?

I'm going to go over some basics so don't be offended; I'm not trying to insult your intelligence.

Speed lever? Maybe you mean the throttle lever, or throttle plate and its cable(?). Could also be the governor control lever (which is actually where the gas pedal cable is connected to on governed go kart engines, at least as-built or from the factory). The throttle is on top of the carburetor and looks like a flat piece of metal with holes in it and a center axis pin. The other wavy lever is of course the choke and should have CHOKE written on it and an arrow.

Choke is just used for starting, and then you flip the choke lever in the opposite direction once it starts. Ensure that the choke is completely off. Engine may run with the choke on but it will be stumbling and smoking and if you try to ride with the choke on, the engine won't make much power, if at all.

The carburetor looks brand new. If there is too much slack in the throttle cable, when the accelerator pedal is pressed all the way down it may not be opening the throttle all the way. You need to ensure that when the gas pedal is at rest (all the way up) the engine should be at idle speed. Make sure that any movement on the pedal is proportional to movement at the engine throttle. You shouldn't be pressing the pedal for more than half the pedal's total travel before the engine revs and the kart moves.

Another issue I see is the hard bend of the throttle cable in photo #4. That could cause binding in the cable and is "not good". If there's enough slack in the cable housing, you should adjust the cable so there's a nice gentle arc in it at that position.

With a clutch, you will want to give it plenty of gas at a complete stop so you're engaging the clutch completely, then ease off after the kart is moving.

1800 is a pretty low RPM. Most of these kart engines were set up to max out at about 3600 revs and that corresponds with the high speed setting on your lawnmower or garden tiller for example. The engines were designed to make their best power at 3600.

 

[KrisMI]

I'm going to go over some basics so don't be offended; I'm not trying to insult your intelligence.

Speed lever? Maybe you mean the throttle lever, or throttle plate and its cable(?). Could also be the governor control lever (which is actually where the gas pedal cable is connected to on governed go kart engines, at least as-built or from the factory). The throttle is on top of the carburetor and looks like a flat piece of metal with holes in it and a center axis pin. The other wavy lever is of course the choke and should have CHOKE written on it and an arrow.

Choke is just used for starting, and then you flip the choke lever in the opposite direction once it starts. Ensure that the choke is completely off. Engine may run with the choke on but it will be stumbling and smoking and if you try to ride with the choke on, the engine won't make much power, if at all.

The carburetor looks brand new. If there is too much slack in the throttle cable, when the accelerator pedal is pressed all the way down it may not be opening the throttle all the way. You need to ensure that when the gas pedal is at rest (all the way up) the engine should be at idle speed. Make sure that any movement on the pedal is proportional to movement at the engine throttle. You shouldn't be pressing the pedal for more than half the pedal's total travel before the engine revs and the kart moves.

Another issue I see is the hard bend of the throttle cable in photo #4. That could cause binding in the cable and is "not good". If there's enough slack in the cable housing, you should adjust the cable so there's a nice gentle arc in it at that position.

With a clutch, you will want to give it plenty of gas at a complete stop so you're engaging the clutch completely, then ease off after the kart is moving.

1800 is a pretty low RPM. Most of these kart engines were set up to max out at about 3600 revs and that corresponds with the high speed setting on your lawnmower or garden tiller for example. The engines were designed to make their best power at 3600.

I said speed lever because in manual they call it "speed control". In the photo #4 you can see the cable runs next to the "throttle lever"? and connect to the lever on the carburetor.

 

[Thepartsguy]

That clutch is mounted outboard and it looks as though you got extremely lucky having a movable drive axle sprocket hub. It’s a good thing because if you couldn’t move the axle sprocket the t/q you bought will not work.

 

[Thepartsguy]

No way look how far the mount sticks out past the engine it’s not gonna work unless you cut holes in the engine mount plate for the chain to ride through.

 

[Thepartsguy]

Or make new engine mount holes.

 

[Thepartsguy]

And confirmed you will be grinding new engine slots moving the engine more to the left in the mount. A t/q driven sprocket rides flush to the block look where that would put your driven sprocket...

 

[JimD]

Go back to his original pictures, slots are already there, someone move the engine over so they would not have to buy a new T/C and went for the clutch only which will not work on the large tires. Look how they lifted the engine up on stilts to get proper chain tension. He was clever but was cheap in not buying the correct drive unit for the kart. Once he gets the t/c it will work fine, he has plenty of room to move the engine over because it had a t/c to start with. It is the 2nd to last of his pictures you can see the original Manco slots on the motor mount plate.

 

[Thepartsguy]

Go back to his original pictures, slots are already there, someone move the engine over so they would not have to buy a new T/C and went for the clutch only which will not work on the large tires. Look how they lifted the engine up on stilts to get proper chain tension. He was clever but was cheap in not buying the correct drive unit for the kart. Once he gets the t/c it will work fine, he has plenty of room to move the engine over because it had a t/c to start with. It is the 2nd to last of his pictures you can see the original Manco slots on the motor mount plate.

I’m kind of curios how this will work for op. post #1 photo #5 shows one engine mount slot off to the left there should be two. Post #1 photo #3 also shows no bottom engine mount slot. Post #1 photo number 5 also shows the one visible slot at the top of the mount. post #1 photo #1 has me wondering if he grinds the slots to use that top slot if his tank is gonna run into the back of the seat before it even gets close to the one visible slot.

 

[KrisMI]

I’m kind of curios how this will work for op. post #1 photo #5 shows one engine mount slot off to the left there should be two. Post #1 photo #3 also shows no bottom engine mount slot. Post #1 photo number 5 also shows the one visible slot at the top of the mount. post #1 photo #1 has me wondering if he grinds the slots to use that top slot if his tank is gonna run into the back of the seat before it even gets close to the one visible slot.

there is only one way to find out TC should be here today. But I won't be able to work on the go kart till sunday probably

 

[Thepartsguy]

Oh wow quick reply can you tell us if the slots off to the left are a full pattern? I only see one slot cut out off to the left. like they started to cut the slots to put the engine there but never finished and mounted it in a different spot with those risers.

there is only one way to find out TC should be here today. But I won't be able to work on the go kart till sunday probably

 

[KrisMI]

Oh wow quick reply can you tell us if the slots off to the left are a full pattern? I only see one slot cut out off to the left. like they started to cut the slots to put the engine there but never finished and mounted it in a different spot with those risers.

My quad is located at my property which I will go to sunday. Will let you know then