By Tod Spaude
Of TS Racing, Inc.
Reprinted from Inside Karting Magazine
I've been asked several times how do I take my engine sprocket and/or belt drivers off. "I can't hold it properly," they say. In the pictures are some methods to hold the driver so you can take the nut off and pull the driver off of the crankshaft taper. In the September 92 issue, Rob Edwards made a drawing and described how to make your own engine sprocket puller.
Two methods which I highly disapprove of are so called "piston stop" and screwdriver. Yes, screwdriver. I have seen where karters have put a screwdriver through the header up into where the top of the exhaust port and piston meets with the screwdriver shank. Boy oh boy, that great blueprint job your engine builder did was just wasted. Believe me I'm not kidding.
How do I hold my driver or sprocket?
Photograph 1 shows large channel locks being used to hold an old piece of belt to protect the driver. Photograph 2 shows a steel plate with a hole for a sprocket to fit through with two dowels across from each other. Photograph 3 shows an impact wrench being used. With the impact wrench, an outside holder is not needed. Photograph 4 shows all tools previously discussed together. Okay, now we have the nut off. Next we have to pull the driver off.
Photograph 5 shows three different pullers. The most well known puller is probably the three tang automotive puller. This works well at times but it has drawbacks. Sometimes it doesn't fit because the driver or sprocket is too small. Also, the carburetor is in the way for sprocket drivers on rotarys. This is where Rob's small puller works great.
For belt drivers, make sure that the tangs do not bend the flange in towards the pulley teeth. If so, your belt may want to jump up onto the flange and result in belt misalignment with the belt spinning off. You may want to inspect your drivers and realign pulley flanges with pliers.
Photograph 6 is a square tubing piece of steel which has a groove to go behind the driver. The bolt is tightened and the driver pops off. These can be purchased at kart shops.
Photograph 7 is one I made because I use Horstman style drivers. It has 3 bolts which screw into the driver and a center bolt to tighten it. If this somewhat looks familiar, all it is a Horstman part number 0800, to which I welded a 1/8"X 1"X 10" long flat steel handle on it. This handle idea can also be welded to Rob's puller to enable the holder to be held easier. Just apply this application in reverse for putting the nut back on.
Photograph 8 shows 2 wrenches being used to take the driver nut off. Again, I don't think your engine builder would necessarily appreciate you twisting or misaligning the crank after he has spent his time aligning your crank. But...that's your choice.
Last footnote: Make sure you use a puller such as photograph 6, 7 or a 3 tang puller. Make sure the bolt which twisted against your crank is in fairly good condition. Some engine builders may use the crank centers at each end of your crank to properly align your crank during rebuilding. Hope this helped or gave you different ideas on holders and pullers.
About the author:
Tod Spaude is President of TS Racing, one of the leading kart shops in America. He has built over 80 National and World Championship engines. He may be contacted at the TS Racing web site TSRacing.com
