Vacuum Pump question

[PARKER MAPLE]

Hey Guys, we have another pump option for this year and its in great working order. This is what I now about it
Precision Vacuum Pump
Model d150
5.6 cfm
rated for a 1/2hp 115v elec motor at 1725 rpm
Pump is rated for 600 rpms.

What Im wondering is the best way to hook this up to a gas power 5hp Honda dc160 engine. I was thinking about a lovejoy fitting and couple the two crankshafts together like a wood spliter uses. Will this work or will the motor over rpm the pump and cause break down? If that dosnt work what about sizing pump pulley and motor and pulley for a belt drive, this would leed me to having pulley size questions? like what size on what end pump/motor.

Any Input Please would be helpfull
Oh releaser is on the way cant wait to do my first vac set up and get my feet wet7165

[maple flats]

You can't run a gas engine that slow, so a lovejoy is out unless you make a jack shaft. I suggest you just get the right pulleys and run it with a belt. Make the pump pulley fairly large and the motor pulley 1/3 that diameter. Then run the motor at 1/2 throttle. At under 6 CFM you will have no problem running it on a Honda 160 CC. I run a 30 CFM on a 200 CC Honda, single belt, 1/2 throttle, 10" pump pulley, 2.5" motor pulley at 20" vac. I also run a 75 CFM, 10" double pump pulley, 2.25" motor pulley, just over 1/2 throttle also on a 200CC Honda. That I can only get 17", above that the belt slips. I'm going to try better belts with teeth, trying to get more inches vac. A jack shaft (motor to shaft on a big pulley, then shaft smaller pulley to a big pulley on the pump) My pumps are designed to run at 700 rpm max, I run under that, at between 450-500.
To run on gas, come up with a larger gas tank, mount it on a stand next to the pump. I use 4.5 gal generator tanks on my 2, the 30 cfm gets about 18 hrs/fill up, the 75 gets about 13-14 hrs. On th larger pump my issue is that a 6.5 HP can't run that size pump well, thus I need to use the small motor pulley for enough power to run it, but then I lose enough drive friction to keep the belt from slipping to get more vac. I think this is my last season on this set up, I'll either get a bigger motor and maybe a 3" drive pulley or build a jack shaft to use bigger pulleys doing the drive for more traction but reduce the ratio and run the motor faster to make up.

[mapleack]

Does your pump have a pulley on it already? If so what size is it? For the rated rpm, if you had a 12" pulley on the pump and a 3.5" pulley on the motor you'd need to run the motor at 2,057rpm. You can get digital tachometers for small motors for about 40 bucks, allow you to dial it right in to where you want.

[PARKER MAPLE]

Thanks Flats, how do you feel about some kind of belt tnsioner set up to help with the belt slipage?? My pump has a 6in pulley so I am figuring on a 2.5in drive pulley, oogdens sugar bush did some math for me on this. This should get me around apprx 1/2 throttle for the 1500 rpm range.
Thanks
MR


You can't run a gas engine that slow, so a lovejoy is out unless you make a jack shaft. I suggest you just get the right pulleys and run it with a belt. Make the pump pulley fairly large and the motor pulley 1/3 that diameter. Then run the motor at 1/2 throttle. At under 6 CFM you will have no problem running it on a Honda 160 CC. I run a 30 CFM on a 200 CC Honda, single belt, 1/2 throttle, 10" pump pulley, 2.5" motor pulley at 20" vac. I also run a 75 CFM, 10" double pump pulley, 2.25" motor pulley, just over 1/2 throttle also on a 200CC Honda. That I can only get 17", above that the belt slips. I'm going to try better belts with teeth, trying to get more inches vac. A jack shaft (motor to shaft on a big pulley, then shaft smaller pulley to a big pulley on the pump) My pumps are designed to run at 700 rpm max, I run under that, at between 450-500.
To run on gas, come up with a larger gas tank, mount it on a stand next to the pump. I use 4.5 gal generator tanks on my 2, the 30 cfm gets about 18 hrs/fill up, the 75 gets about 13-14 hrs. On th larger pump my issue is that a 6.5 HP can't run that size pump well, thus I need to use the small motor pulley for enough power to run it, but then I lose enough drive friction to keep the belt from slipping to get more vac. I think this is my last season on this set up, I'll either get a bigger motor and maybe a 3" drive pulley or build a jack shaft to use bigger pulleys doing the drive for more traction but reduce the ratio and run the motor faster to make up.