[steven Banks]

Evening,
 is it normal for the pressure to drop from 400psi to around 250psi when the pull the trigger on the wand? Seems like a big drop to me.

[Simon Gerrard]

Steve,
It should only drop by around 50psi. Your check valves may need changing.

Simon

[nevil]

I think you need a spare blower Steve. :

[John Kelly]

Check your inlet filter it may be starved of water.

[garyfindlay]

air lock?

[richie]

What machine is it you have.  In the past i have found that with some HydraMaster truckmounts if the pressure drops more than 50 psi then it may be the regulator.  Wind it all the way out, remove the retaining clip and washer, remove the bullet like thing.  Give the bullet a clean apply a tiny amount of grease then fit it all back together.

[Jim_77]

Is it cleaning OK?!  Have you noted the pressure drop to be different in previous times, with exactly the same wand/hose length/jet sizes?

The higher the total jetting the more the pressure will drop when wand trigger pulled.  It really does not matter as long as everything is working properly.

[steven Banks]

Steve,
It should only drop by around 50psi. Your check valves may need changing.

Simon

Could be, I'll take a look Simon.
Thanks for the advice guys, I'll take a good look at the machine.

I was thought it could be the pump seals in the cat pump

Many thanks,
Steve.

[Simon Gerrard]

Steve,
Take them out one at a time, if one is damaged it will be fairly obvious. Failing that it could be the seals which is a bit more fiddly.

Simon