I have an old camel back drill press with a leather belt drive system. When I use the small pulley, everything works fine. When I switch to a larger pulley, however, in order to increase rpms, the belt keeps slipping off. I have tried realigning leftwards and changing different tensions, but nothing has worked. Does anyone have experience with this?

Hellow, Normally motors get overheat when over loaded.In your case,when you are runing with a bigger motor pulley,motor needs a higher torque to turn a drill bit with a small pulley and vice versa .So you have to use a small motor pulley with somewhat bigger drill bit pulley and then drill bit has enough torque without much load to the motor. Also when you replace a motor, You are required to find a motor with the same output power or higher power when compared with the original motor.RPM of the motor is not much affected . Thanks.

15" Rockwell Drill Press pulley removal? - The Garage Journal Board

www.garagejournal.com > ... > The Tools > General Tool Discussion
May 3, 2012 - 7 posts - ‎2 authors I have 15" Rockwell Bench top drill press 15-017 I think circa 1971. ... You have toremove the machine screw and the pulley and bearing ... Drill Press Pulley Problem
19 posts
Aug 31, 2013
Old COMPANION bench top drill press disassembly?
20 posts
Mar 5, 2013
More results from www.garagejournal.com

If the drill press has multiple pulleys, you move the drive belt up and down. Larger motor pulley to smaller drill pulley has higher speeds, and vice versa.

Your drill spindal might be freewilling, if it is your not ingaiging the drive. Some drill presses have a locking switch and or lever to ingage to make this work.

If we use the treadmill daily it might need maintenance regularly. Running of 180 hours on the treadmill might lose the belt. Drive belts usually last for longer time of 5 to 7 years.So you have to adjust the tension of the belt.
Keep enough tension in the drive belt
If a user wants to improve the motor efficiency it is necessary to connect the motor to the front wheel which helps the belt to spin.
Too little tension results in slippage, excess heat and high-pitched noise, or too tight belt produces tension causing stress on belts, bearings, and shafts. Prevent premature motor failure by adjusting the belt at a suitable place. The belt should be fixed half an inch of play.
To improve the efficiency of the motor align the belt properly and lubricate it on time. Keep in mind such useful options may help the user. When the belt slips off the track, the friction between the belt and drive pulleys causes the belt to overheat. If you hear a high-pitched noise, it's time to replace the belt with a new one.
How to Ascertain that the drive belt can still be used?
If you test Front-wheel by walking on the treadmill and the belt stops but the motor is still moving, It means that the drive belt is loose and needed to be tightened or replaced.
Keep in mind
There are some exercises that are not suitable for the treadmill like jumping on it. This kind of usage can be rough on your treadmill and lead to your treadmill belt slipping.

I'm not familiar with this particular model, but most drill presses have a similar design. The top cover should flip up, exposing the the pulleys and belts. At the back end of the machine where the motor is located, there should be one or two bolts that put tension on the motor, which in turn tightens the belts. When these bolts/nuts are loosened, it should put slack on the belt (s)., allowing the belt to be taken off. There may also be an tensioned idler arm/pulley which puts tension on the belt, such as an intermediate belt. That pulley can be moved to release tension as well. After new belt(s) is installed re-tighten the motor tensioning bolt/nut, allowing for some slack in the belt.

See the picture below. The small red circle shows the locking screw on the right side of the drill. There is another locking screw on the left side of the drill. Loosen them both a half turn. The larger red oval is the handle to pull the motor closer to the spindle, thereby loosening the belt. Once loosened, it is easy to move the belt. Then use the handle to push the motor back, which tightens the belt. Keep pushing on that handle with your right hand while you tighten the locking screw on the left side of the drill with your left hand. Once you have that tight then tighten the right side locking screw.
Good luck! I hope this helps.

I had the same problem and searched extensively for a replacement pulley, but couldn't find one. I thought I'd try something else and began looking at Love Joy variable speed pulleys. They function the same way and are much heavier duty that the cast pewter used by Delta. The one problem, they are EXTREMELY expensive. Tried ebay and found a number of different brands and sizes. I recently found and purchased a Reeves variable speed pulley 850C 5/8" bore & 5" OD off of Ebay for just under $30. Well, the motor shaft is just under 5/8" but larger than 9/16" so I was going to use a metal 1/2" ID x 5/8" OD spacer as a shim and file the inside down to the motor shaft diameter, which would definitely work. Fortunately I had an old 1/2 HP motor from an old drillpress and it had a 5/8" shaft. Dropped the Reeves pully right on and mounted it on the DP350 and it ran like a charm. It's a little off of alignment and I had to cut a hole in the top cover for the Reeves pulley to protrude out an inch or so, but other than that it works great. My only fear is that the front pulley might explode now. Guess I'll have to wait and see. I'll bet there'll be a lot of searchers for a 5" OD variable speed pulley on ebay! Hope yours works as well as mine!

Hi This is quite complicated but I'll try and simplify this for you:
If this is a Panasonic upright then there are two drive belts as you know. Once you take off the sole plate (where the beater bar is) by undoing screws and the beater bar is looking at you, you would have to take off the smaller belt motor pulley first before putting on a new larger drive belt. If the smaller belt is still intact and you only need to replace the larger belt, you'll still have to take off both belts to put on the new drive belt.
Motor pulley belt has to be taken off first then the old drive belt, then grasp the beater and slide on new larger drive belt before having to attach the motor pulley belt and then the larger belt onto the motor pulley. Once all belts have been attached ensure that the beater bar is pushed in correctly before you screw the sole plate back on.

hi The drive belt (or belts) of a washing machine may become worn or damaged, causing noisy operation or stopping the washer entirely. A damaged drive belt is easy to replace. Remove the back panel of the washer to gain access to the belt. To remove the belt:
Step 1: Loosen the bolt on the motor bracket and move the motor to put slack in the belt.
Step 2: Remove the old belt and stretch a new one into place on the pulleys.
Step 3: To put tension on the new belt, use a hammer handle or a short pry bar to push the motor into position while you tighten the bolt in the adjustable bracket. The belt should have about 1/2 inch deflection when you press on it at the center point, midway between the pulleys. If the belt is too loose, it will slip on the pulleys, causing the machine to malfunction. If the belt is too tight, it will wear very quickly and will probably become so hot that it will start to smoke or smell.
Loose pulleys can also cause problems. Most pulleys are fastened to shafts with setscrews around the hub of the pulley. These screws must be tight or else the pulley or belt will slip. The resulting malfunction may seem to be caused by a faulty motor, but it can be corrected by tightening the pulleys and adjusting the belt. For this reason, always check the belts and pulleys before working on the motor.
thank u................