Help with 8gpm unloader please

innovativewash

innovativewash

New member
I just replaced a pressure unloader on our 8gpm maching with a K7 unloader for 8gpms and cant get it to stop cycling every 2 seconds. I changed out the bypass connector to make sure we had plenty of flow. Still cycling. Anybody had this problem before?
 
I have to fix this fast to get this rig back on the road. Please help.
 
Cycling while spraying or not? K7's are finnicky about flow. If it's cycling with the gun off, the bypass orifice isn't small enough.
 
What size hose line are you using for the bypass line? I've heard about these issues with the K7 and they are solved by making sure the bypass line has enough restriction..... Needs to be 1/4", no bigger.
 
Bob Keenan said:
What size hose line are you using for the bypass line? I've heard about these issues with the K7 and they are solved by making sure the bypass line has enough restriction..... Needs to be 1/4", no bigger.
Click to expand...
Half inch bypass hose on all our other units too. They work fine.
 
I spoke to Russ and he gave me some tips to try tomorrow. Thanks Russ
 
mike barrett said:
I think the bypass orifice should be a #2, i'll check mine in the am to make sure.
Click to expand...
Thanks Mike let me know if it is a number 2. Mine is a 3
 
Nigel, that is what my surface cleaner (that I won at the Tampa RT) did when I first hooked it up. It came with a pair of 1502 nozzles on it, which of course are too small of a nozzle for the K-7 with the #2 oriface (which operates in the range of 4.2 - 6.6 gpm). 15025, 1503 or larger and the K-7 would not have cycled.

James if you are not using a nozzle (or a combination of nozzles) that allows for at least a 6.6 gpm flow (possibly higher) on you #3 oriface, it will cycle like the video Nigel posted.
 
HighTide said:
Nigel, that is what my surface cleaner (that I won at the Tampa RT) did when I first hooked it up. It came with a pair of 1502 nozzles on it, which of course are too small of a nozzle for the K-7 with the #2 oriface (which operates in the range of 4.2 - 6.6 gpm). 15025, 1503 or larger and the K-7 would not have cycled.

James if you are not using a nozzle (or a combination of nozzles) that allows for at least a 6.6 gpm flow (possibly higher) on you #3 oriface, it will cycle like the video Nigel posted.
Click to expand...
Whats puzzling is it constantly cycles when the ball valve is off.
 
Flow-Actuated k-7 unloader issues

most Flow-Actuated unloaders are flow-sensitive in pressure-mode
AND in bypass mode as separate functions.

If it fluctuates in Bypass mode..
the oriface size AND the restrictions against the bypassing water are critical.

When it fluctuates with the gun OPEN..
the outlet oriface, the outlet Nipple,
and your nozzle size, and hose length, and every other "flow-restriction" inbetween..
..are ALL critical.

If you are simply replacing an unloader with a new one of the same model..
use the old orifaces, and you are less likely to have issues.

If you do have issues..
look for flow restrictions.

If it fluctuates in bypass..
squeeze the bypass hose with a pair of pliers to see if the fluctuation stops or slows..
that means you need a smaller bypass oriface to "hold it in bypass".
Sometimes when the recommended bypass oriface is plumbed to dump effrtlessly to a holding tank,
instead of bypassing back to the inlet side of the pump..
there's not enough back-pressure to "hod" the unloader in bypass mode.

If you're still having issues.. call me..
we understand these unloaders thoroughly.
 
Last edited:
mike barrett said:
Mine has a #2 oriface and 3/8 bypass hose and don't cycle!
Click to expand...

So.. it has #3 outlet nipple, #3 outlet oriface,
and #2 bypass oriface. right ?
..that's what I'd expect out of a 8gpm system that is tank fed.

..and if you want to be able to "reduce flow" ..
like when using a 21" vacuuming surface cleaner on an interior job.. at 6gpm..
using a #2 outlet oriface under the #3 outlet nipple should be fine,
..and function properly with full flow OR reduced..
best of both worlds.
:{)
 
Last edited:
You must log in or register to reply here.
Back
Top