hardi pump problem

[Skimmer]

Its not very likely but check the diaphram bolts are tight if not fitted properly they can come loose causeing the diaphram's not to move much so no pressure builds,the diaphram's will still seal around the bolt so the pump won't be leaking as in a split diaphram.
Are you sure it's the pump and not an air leak from the filter seal on top of the tank.

 

[Dave W]

yes you were spot on thanks although I had it off and checked it numerous times but did the trick when I swapped it

 

[Richard Smyth]

We have converted our sprayer to bottom suction from the tank. No more problems like this now.

Richard

 

[Chrisw]

We have converted our sprayer to bottom suction from the tank. No more problems like this now.

Richard

Was going to ask if this was possible on the Hardi as the current system seems totally daft to me.
Did you just put a new outlet in the bottom and re-route the hose from the top to the new one underneath?

 

[Richard Smyth]

Yeah put a new 50 mm hole in the sump and put in a nice big easy access filter, rerouted existing hose minus about 2 meters and been very happy since. We were always having problems and actually had to run without the filter in top of tank to get it to operate.

Only just remembered it when read skimmers post.

 

[David.]

It is a good idea for the reason that you can clean a blocked filter in field without losing any liquid, rather undermined by the fact that any floating crap/foils etc, up the tube can only be reached when tank is full to overflowing.

 

[Chrisw]

It is a good idea for the reason that you can clean a blocked filter in field without losing any liquid, rather undermined by the fact that any floating crap/foils etc, up the tube can only be reached when tank is full to overflowing.

Would be a good idea then to put a stop tap in the line before the filter, just in case?

 

[Richard Smyth]

Yes we didn't to start with but have now. My other sprayer has a filter with valve in it. Turns water off when removing the filter.

 

[Kcoleman]

well after many hours stressing and messing and re-sealing (even borrowed a similar pump off a mate and gave same symptoms) I eventually traced it to the large red cap on the top of the suction pipe that houses a filter. Had it off and checked it and all looked ok but obviously was sealing properly.
Running nicely now.
Thanks for all your help fellas

Can I ask if there is one or two O rings inside the inside of red cap,?.. I have the same problem (heavy pulsing) and I can only see one O ring that is the same diameter of the filter inside the cap.. does this seem right?

 

[Dave W]

Can I ask if there is one or two O rings inside the inside of red cap,?.. I have the same problem (heavy pulsing) and I can only see one O ring that is the same diameter of the filter inside the cap.. does this seem right?

Long time since I’ve had anything to do with them. But there’s only 1 critical seal in the cap. Square section O ring the same diameter as the main threads.
There may be another seal on the filter but that won’t have any effect on suction

 

[Kcoleman]

Long time since I’ve had anything to do with them. But there’s only 1 critical seal in the cap. Square section O ring the same diameter as the main threads.
There may be another seal on the filter but that won’t have any effect on suction

Thanks for that.. looks like I'm missing that square section seal

 

[quattro]

Can I ask if there is one or two O rings inside the inside of red cap,?.. I have the same problem (heavy pulsing) and I can only see one O ring that is the same diameter of the filter inside the cap.. does this seem right?

Does it only pulse when level is getting lower in tank

 

[Kcoleman]

Does it only pulse when level is getting lower in tank

No it's pulsing even when tank is full to the top.. it was running perfect until the other day.. cleaned all filters and checked pipes for leaks etc..

 

[Kcoleman]

No it's pulsing even when tank is full to the top.. it was running perfect until the other day.. cleaned all filters and checked pipes for leaks etc..

Does anyone know if there's supposed to be Jubilee clip on the diaphragm at the pump to seal it air tight?

 

[quattro]

No it's pulsing even when tank is full to the top.. it was running perfect until the other day.. cleaned all filters and checked pipes for leaks etc..

If its pulsing it’s more likely sucking air or maybe a valve in the pump