clutch and sprocket alignment

[jvandyke]

My son got kart fever (Dad is coming down with a good case too)
We bought a used rolling frame that I think is pretty good and have a Tecumseh 5hp. The clutch on the engine looks pretty sad, the sprocket is worn so the teeth are pointed sharp. Looking to find what brand it is and either replace the sprocket or buy a whole new clutch, anyway, first issue I see is that when we set the engine on the plate aligned over the slotted holes the clutch and wheel sprocket are not aligned. Do we drill new holes in the plate, get a new clutch first, and see about aligning that on the shaft to match, or what? I'm am totally ignorant of karts, I can fix cars all day long so I think we'll get there.
The engine runs but the carb is off (ether straight down it's throat and it fires).
Any and all advice welcome (I have been searching!)

 

[OzFab]

Welcome to the forum...

That sounds pretty typical of tecumseh carbs, the weakest link in the metaphorical chain...

If the teeth on the clutch sprocket are worn, chances are, the clutch is all but dead too; it's probably easier to buy & install a whole new clutch rather than fiddle around changing the sprocket.

Unless the sprocket is welded to the axle (WHICH IT SHOULDN'T BE) it'seasier to move the axle sprocket than the engine... unless there's some clearance issue...

 

[firemanjim]

Welcome to DIYGK and kart madness.... kids are a great excuse to have/build karts.... lol
Without pics ,its hard to tell, but you most likely only need to adjust the clutch spacing. Buy a new Comet clutch or the like and when you install it and motor, you should find a sweet spot that it all lines up. When you do, tighten down the set screw on the backside of clutch to secure it in place....the mfg engineered them slots to be just in the right spot. Its all in the clutch spacing i bet.... Is it a one wheel peel or a live axle? Got pix?

 

[DeathStarr89]

How far off are they?

You can install the clutch either way (Sprocket inbound or outbound).. Maybe someone flipped it around?


For the carb, give it a good cleaning. It should come back to life.

 

[firemanjim]

O yeah, you said carb is OFF and you where spraying ether into bore.... why is the carb off? Is that how you got it?

 

[jvandyke]

thanks for the tips guys,
clutch is Max torque, has a #4 on the back plate, it "looks" okay but I ended up taking it all apart in an attempt to get it off the shaft, I couldn't find any set screws, I guess it's supposed to have a bolt on the end of the shaft (I do see a keyway) no bolt. Probably frozen on the shaft? I'll hit with penetrating oil and try a wheel puller, I guess.
I'm cheap but try not to be stupid. A shop near me had a new clutch for $35 so bought it, I think I got the right one, I gave them the engine numbers, old clutch had 12 teeth, so does new. Sorry no pics yet. Yes, single wheel drive. Carb is off as that is how we got the (free) engine. Gas tank is gone and was told it was cracked and useless (but I might be able to get it back to "fix" as a new one is $50 (ouch). Also there is no air filter box so I have to buy or make one. I did notice the needle and seat were gone under the float, got a kit for that, got new gaskets for carb install.
So, will attempt to pull the old clutch off the shaft, install new in a position that is favorable for wheel sprocket alignment, get the carb put back on (throttle cable attachment and all that is a mystery yet).
Cart frame came with a chain, looks okay, will try it. Wheel sprocket is 72 teeth so I believe the 12 tooth clutch is appropriate, didn't think to check wheel diameter.
My son is really excited and this might be just the perfect way to "connect" with my almost 13 year old son. (my 18 year old was about cars and motorcycles for the last few years, we "connected" plenty trying to keep ancient foriegn sports cars happy and "home made" street fighter motorcycles. Thanks a million, we'll get it ripp'n down the road soon I hope.

 

[jvandyke]

content below

 

[jvandyke]

I thought I added some pictures. Weird.
Got old clutch off, had to cut into it and get aggressive with a puller, finally pulled free. Key was gone, just a pile of rust. Bit worried that in test fit the new clutch will have to sit outboard quite a ways and not push onto the crank shaft as far I think it should, will look at wheel sprocket adjustment but I don't think there is any to be had.

 

[jvandyke]

got needle seat kit, manifold gaskets, cleaned the carb, pushed that white spongy thing (I assumed it was the seat) down into the hole, keeping it square, put the needle in, adjusted float (no idea how the spring goes on) bolted on carb, fired and ran!!! spooky.
Big questions on how to connect the throttle linkages but we're closer. Good night's work!
yah, carb was off when got, needle seat gone, no spring

 

[firemanjim]

Nice lookin kart . I agree, its a great way to STAY connected too... I'm a father of 5 with 1 in the oven. Ill bebbuilding karts, buggies,and cars for the next 30++ years.....

 

[jvandyke]

it idles, dies on tip in, waiting on pieces to reconnect governor,
back on topic:
New clutch must be set on end of motor shaft, hanging off it about 1/2" to line up with wheel sprocket. Thinking this with set screws and an end bolt should be okay?
Chain is a bit loose so might raise engine a bit with washers under mounting bolts. Also okay?

 

[landuse]

You can raise the engine with washers, or just move the engine forward a bit in the engine mount slots.

 

[jvandyke]

sliding it fore and aft doesn't take up enough slack for my liking. Pulled a link pair but that left it way too short. Could be mis-matched chain/sprockets I guess but it's close. Will try a few washers under the engine. Not sure how to tell if you have the "right" chain and sprocket combo. Teeth count is good (72/12), just want the "fit" to be good.

 

[landuse]

sliding it fore and aft doesn't take up enough slack for my liking. Pulled a link pair but that left it way too short. Could be mis-matched chain/sprockets I guess but it's close. Will try a few washers under the engine. Not sure how to tell if you have the "right" chain and sprocket combo. Teeth count is good (72/12), just want the "fit" to be good.

Chains and sprockets have different pitches. If you get a #40 chain, then you have to us a #40 sprocket. You have got to measure the distance between 2 teeth for the pitch. 3/8" distance is a #35 chain, 1/2" is a #40

You can use half links as well if you want to shorten your chain

 

[jvandyke]

super, thanks that's the info I need then, I'll check the sprockets for pitch.

 

[edgeblade]

Any udates on this ?......did u get it working?

 

[jvandyke]

yes, I think it all moved to a different thread or something, I had the wrong clutch sprocket so got another whole clutch (the chain was a 40) then I just mounted the clutch hanging off the end of the shaft a bit. Works, goes well, steering is poorly designed and the engine won't idle but it works. I did put a bolt in the end of the shaft for some insurance since mounting the clutch like that probably isn't the best solution.

 

[edgeblade]

Okay cool glad to know u got it rumning at least

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