Getting higher pressure for wash bays

[Jason Studer]

I have both Cat and Arimitzu Pumps, and the highest pressure I can get In the bay is 1300 psi with a cat and 1100 psi with Arimitzu. All hoses except wand hose are 3/8", and wand hose 1/4". switching to 3/8 hoses brought pressures up about 150 psi. Would switching from 3 hp to 5 hp motors help or maybe a smaller pulley then 6" on the pumps?

These bay are any where from 60' -100' away from the pumps.

Thanks for your input. Jason

 

[Eric H]

What model Cat pump and what size tip are you using? I suspect you are on the right track asking about pulley size. You may not be getting enough flow for the pressure that you are trying to get.
There is a chart in the Cat manual that shows the correct pulleys for the pressure and flow you want. I think you can find the manual on the Kleen-Rite website. You want to match the flow rate and pressure as close as possible to the pulley/pump speed to prevent prematurely wearing out seals.

 

[Randy]

I run my Cat 310 pumps at 1500psi with a 3hp motor and a 1505 nozzle. We've been running them like that for over 30 years. Very seldom do I have to replace pump seals. I'll have to check and see what size pulley sheaves we are using.

 

[I.B. Washincars]

Leaving everything else the same, increasing pump RPM is what will increase the pressure. A 5HP motor is spinning at the same RPM as the 3HP. You may need to change to a 5HP to prevent overloading, but not for pressure. Greg with Arimitsu can probably steer you in the right direction as to what pulley sizes you will need. He will need to know what size tip you are using to give you accurate info.

 

[MEP001]

Tip size and wear can also make a big difference in the maximum pressure you can reach. Do you change yours routinely? What size are you using? In a year an --06 tip can go from 3 GPM at 1000 PSI to well over 3.5, so even if your pulleys are sized to run 1500 PSI at 3.5 GPM with new tips you won't get close to that pressure when they're worn.

 

[Jason Studer]

I lied about pulley size
8" at pump, 3 1/2" at motor
2506 tip size
I always check pressure with a wand with a gauge and new tip, this wand never gets used except to check pressure.

Cat 310 and Cat 5cp2120w

 

[MEP001]

3 1/2" at the motor is too small. I tried 3.75" motor pulleys with the 8" pump pulley, and with 2507 tips could just barely reach 1000 PSI. With 2506 the pressure would drop below 1000 after about three months. 4" motor pulley would be the best as long as you don't plan to go over 1400 PSI with a --07 or 1500 with a --06 tip.

 

[slash007]

I lied about pulley size
8" at pump, 3 1/2" at motor
2506 tip size
I always check pressure with a wand with a gauge and new tip, this wand never gets used except to check pressure.

Cat 310 and Cat 5cp2120w

where are you putting the pressure gauge in this setup?

 

[I.B. Washincars]

where are you putting the pressure gauge in this setup?

IMO, the most sensible/easiest place would be to put a street tee between the gun and barrel, then screw the gauge into the tee.

The more I think about it, the barrel wouldn't be needed. Just put the nozzle in the tee as well.

 

[wash4me]

3 hp is fine. May need to adjust the overloads up to full load amps x service factor. Like was said above call your dealer or figure out the tip size and rpm/pulley size you need. Personally I would copy what Randy does then you don't have to figure it out!

 

[slash007]

IMO, the most sensible/easiest place would be to put a street tee between the gun and barrel, then screw the gauge into the tee.

The more I think about it, the barrel wouldn't be needed. Just put the nozzle in the tee as well.

Good point. Is there really any reason to have the barrel other than wanting to point the water further away?

 

[Randy]

I measured my pulleys this morning the motor has a 2 groove 3 1/2" pulley and the pump has a 7 1/2" pulley, I'm using 2 - B52 belts on the set up.

 

[Jason Studer]

The gauge it in a tee between trigger and wand.

Greg from Arimizu called me and then stop by my shop/wash and agreed with all that was said on the forum, this gives me a few things to try when I can shut a bay down. Thanks again for all the support.

Jason