Delaval 73 spitting oil, running hot

[Starting Small]

I have a Delaval 73 that I got running today. Pulling about 27 inches at the pump on 100 taps. It has a 1.5 hp motor with it and no way to adjust the rpm of the pump. After a half hour of running, oil was spitting out the exhaust and it was too hot to hold my hand on. A few questions:

1. Is the 1.5 hp too big of a motor and could this be why it is running hot, too many rpm's?
2. Should I replace the motor with a gas powered .75 hp motor, right now it is hooked up to a generator.
3. After looking at the pump, it might not be 100% level it could be slightly pitched away from the exhaust. Could this be an issue?
4. Can I install a dimmer switch to help reduce the rpms and hopefully keep it cooler.
5. Is it running hot only because it sparayed out a good chunk of oil?
Thank you all do much,
-Dave

[maple maniac65]

I run my 73 with a 3/4 horse at about 1500 rims 23 inches. I have let it run three days straight before it is hot and does blow oil

[lpakiz]

If you look at the tag on any electric motor, you will see that they run a set RPM. Doesn't matter if is a 1/2 or 5 HP, they run at the speed on the tag.
So no, the size of the motor isn't the cause.
If it's belt drive, you can vary the DRIVEN pulley speed by changing pully sizes. Smaller on the motor or larger on the pump will result in slower pump speed.
I would steer WAY clear of a "dimmer" switch. If you want to have a variable speed motor, better see an electric motorman who specializes in these items. You are better off to change pulleys to get the RPM you want.

[Starting Small]

Thank you guys, Ben (Breezyhill) is going to get me some size recommendations on changing the pulley to reduce the RPMs. I will keep you posted as to how it works, thanks again I appreciate it.
-Dave

[Shaun]

I have a delaval 73 that was used in sugaring. It has a 1.5 hp @1725 RPM with a 5 inch pulley. The pump itself has an 8 inch pulley. I have not used it yet, I cannot attest to how it works,

[Shaun]

After looking around it seems the 5 inch drive pulley is to large? Would other agree for the D-73 pump at 1725 RPMS? Looks like a 2.5 inch may be better for this pump.

[BreezyHill]

I agree that is very large.

My largest ever used was a 4" to meet the tags max rpm.

use Pi x D for the distance around the pulley for inches of drive per RPM of motor.

Then Pi x D for the Driven pulley ( on the pump). Divid this into the motor distance and you have Pump RPM.

Example:
Pi=3.14
Drive Pulley is 4"
Driven Pulley is 8"
3.14 X 4" = 12.56" 12.56" X 1725 = 21666
3.14 x 8" = 25.12
2166/ 25.12 = 862.5 RPM for the pump

5"=1078 RPM

Tag on a 73 lists 620 RPM 1/2 Hp, 750 RPM 3/4 Hp, & 1000 Rpm1 Hp

I am running a 3.5 " pulley for 755 RPM with a 1 Hp motor that was on my parts shelf.

In end of season the fan would run on her to keep her cool at 170 degrees. Box fan on low. Don't like readings of 185 and up.

Ben