10 Tooth #35 Chain Centrifical Clutch With Set Screw
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@Jim Donovan would be the man to talk to.
Skipp - you are correct in that we have quit putting set screws in the 3/4" clutches but we still put them in the 5/8" bore clutches since many of those old cranks are not drilled and tapped.
The 10 tooth #35 chain sprocket can fit either the 5/8" or the 3/4" crankshaft but it is a two piece clutch. The 5/8" bore clutch would have a bushing in it but the one going on the 3/4" crankshaft would be steel on steel. The bore of the 10 tooth sprocket is 3/4" to start with but we hone it open to .753 so it can free spin on the crank and we include a package of anti-seize with the clutch. Now here is where you have to use some common sense-- if you INBOARD the clutch (sprocket next to the crankcase) you put the anti-seize on the last 1" of crankshaft and if you are OUTBOARD mounted then you put the anti-seize in the bore of the sprocket. What you are trying to do is keep that "stuff" out of the inside of the drum.
The 10 tooth #35 chain sprocket can fit either the 5/8" or the 3/4" crankshaft but it is a two piece clutch. The 5/8" bore clutch would have a bushing in it but the one going on the 3/4" crankshaft would be steel on steel. The bore of the 10 tooth sprocket is 3/4" to start with but we hone it open to .753 so it can free spin on the crank and we include a package of anti-seize with the clutch. Now here is where you have to use some common sense-- if you INBOARD the clutch (sprocket next to the crankcase) you put the anti-seize on the last 1" of crankshaft and if you are OUTBOARD mounted then you put the anti-seize in the bore of the sprocket. What you are trying to do is keep that "stuff" out of the inside of the drum.
Since the Briggs cranks are not heat treated it is just a little more work to drill the end of the crank and tap it. You don't have to drill the standard 5/16 -24 that Briggs uses but a 1/4-20 if adequate. You don't want to fix the clutch to the crank, there should always be some lateral movement of the clutch on the crankshaft to self align with the rear sprocket which NEVER runs true.
Making changes is never and easy decision. The instruction donut with the clutch has always said don't use the set screws if the engine is drilled and tapped but who reads instruction? We still do drill some 3/4"clutches but they have to requested by the dealer.
Making changes is never and easy decision. The instruction donut with the clutch has always said don't use the set screws if the engine is drilled and tapped but who reads instruction? We still do drill some 3/4"clutches but they have to requested by the dealer.
Ok I’m listening but so many questions….so if you’re using a clutch in a 3” shaft you let it float the whole shaft….i understand the chain will keep it somewhat aligned….and if the clutch sits at the very end of a short shaft….no worries of it self aligning off the shaft? I ALWAYS use both set screws as tight as I can get them….my clutches don’t work? Thank you for your knowledge….
First, the short shaft situation. Don't use an "SS" style Max-Torque if the shaft is 1.5" or less because the sleeve of a Max-Torque is 2 pieces and they will be pulled apart in a very short time without the full support of the crankshaft. The only exception would be a racing clutch which is a one piece hub and sleeve. Putting an extension onto the crankshaft put a lot of pressure on the bolt size used to hold on the extension which I would lean towards a 3/8 bolt to hold things together.
Now for the long shaft cranks, leave the crank long don't cut it off. It is easy to find a 3/4" spacer using either some copper tubing or fittings cut to length or some PVC. Or you can go out and buy some 3/4" lock collars. If you decided to use the PVC or copper tubing, since it is a spacer it won't get much wear and tear and it will hold up. Put the clutch on first and see where it is centered to the rear sprocket, mark both ends of the clutch as it sits on the crankshaft. Take off the clutch and measure the lengths of the spacer you need to make from the step in the crank to your mark on the shaft and cut your spacer and do the other end for the second spacer. Using the lock collars, slide the first on on before your put on the clutch and the second one on after the clutch is in place center the clutch to the rear sprocket. Slide the collar back from the clutch the thickness of a penny (about .060) then tighten down the lock collar. My favorite measuring device, a penny, which about .060 thick and exactly 3/4" (.750) in diameter, so now you know it is worth keeping a perrny around to measure things.
Now for the long shaft cranks, leave the crank long don't cut it off. It is easy to find a 3/4" spacer using either some copper tubing or fittings cut to length or some PVC. Or you can go out and buy some 3/4" lock collars. If you decided to use the PVC or copper tubing, since it is a spacer it won't get much wear and tear and it will hold up. Put the clutch on first and see where it is centered to the rear sprocket, mark both ends of the clutch as it sits on the crankshaft. Take off the clutch and measure the lengths of the spacer you need to make from the step in the crank to your mark on the shaft and cut your spacer and do the other end for the second spacer. Using the lock collars, slide the first on on before your put on the clutch and the second one on after the clutch is in place center the clutch to the rear sprocket. Slide the collar back from the clutch the thickness of a penny (about .060) then tighten down the lock collar. My favorite measuring device, a penny, which about .060 thick and exactly 3/4" (.750) in diameter, so now you know it is worth keeping a perrny around to measure things.
Minimichael- It is the drum and sprocket I want to see free spin on the sleeve of the clutch once it is slide on the crankshaft. If it is a one piece clutch--when you pick it up by the sprocket the shoe assemble lifts with it at the same time. 2 piece clutch in a 10 tooth #35 chain would not have a bushing if it is going on a 3/4" crankshaft and the drum and sprocket is NOT attached to the shoe assembly. If it was going on a 5/8" crankshaft it would have a bushing in it.
A 10 tooth #41 or #40 sprockets all have a bushing in them.
You can buy some anti-seize without abrasives in them. I usually coat the crankshaft before I slide a clutch on with anti-seize so I can get it off down the line. It certainly will never hurt the crankshaft since nothing is spinning on the crank. The only exception to that would be the 10 tooth #35 chain sprocket on a 3/4" crank which is steel on steel but the only time it is free spinning is at neutral and what kid stays in neutral longer than 10 seconds?
A 10 tooth #41 or #40 sprockets all have a bushing in them.
You can buy some anti-seize without abrasives in them. I usually coat the crankshaft before I slide a clutch on with anti-seize so I can get it off down the line. It certainly will never hurt the crankshaft since nothing is spinning on the crank. The only exception to that would be the 10 tooth #35 chain sprocket on a 3/4" crank which is steel on steel but the only time it is free spinning is at neutral and what kid stays in neutral longer than 10 seconds?
https://www.ebay.com/itm/186380571023
Not sure if you found what you were looking for . This isnt mine but i remember reading this thread and figured id share
Not sure if you found what you were looking for . This isnt mine but i remember reading this thread and figured id share
