Air lock?

[Truckcab79]

I have the Jetmac Loncin 7hp which I love. Great bit of kit. Used it today to blast as much muckand built up paint as I could off a deck prior to a repaint. Did the job brilliantly.

However on starting I got no water. Only use it every few weeks and it’s quite new to me so thought maybe I’d done something stupid. Started fine. Engine ran fine. It’s fed from a buffer tank and both feed and return pipes were submerged. Pressure release valve open but nothing coming out.

Shut it down after about 15 seconds. Checked it all over. Tried again and water came out relief valve as it should.

I’m assuming air lock in pump or feed pipe unless someone can suggest otherwise???
After that ran totally normally for about about an hour.

Just want to set my mind at ease if it happens again. And if it does what I should do. Doesn’t seem right to continue to run pump and engine without water passing through in the hope that it starts flowing. Do I back-fill the pipes with a hose maybe?

Many thanks in advance.

 

[Truckcab79]

Funnily enough I was about to post this again when my old thread came up. Forgot I’d asked and can’t see any answers since.

First job of the season on Saturday so took it all out today. It’s been carefully stored in a heated garage. Oiled and WD40 beforehand etc.

Took it out today to run in advance of the job. Had same issue as in my original post. Not sucking water. Back-filled with hose until it came out the relief valve. Restarted and water coming out of hose but a bit sporadic. Fitted a nozzle and after a few spurts then off we go. All good from then on.

Am I missing something. Is it normal? And does the pump draw better when a nozzle is fitted. Could be coincidence but seemed to be the thing that made the most obvious difference.

Anything I can do or that I’m not doing to help the first start I only even worry about it as the first few times I used it last year it started, spurted out of relief valve straight away and then all good from then on.

 

[Truckcab79]

Also am I at any risk letting it run without the water going through it. I only ran if for a few seconds each time today but then wondered if that was part of the issue. I wasn’t giving it long enough to clear any air maybe.

Are the pumps meant to be self-priming anyway? I’m running it from a buffer tank so until it begins to draw then there is no water in the pump. Catch 22 I suppose but I wouldn’t expect to have to prime it before each use.

 

[Pjj]

Funnily enough I was about to post this again when my old thread came up. Forgot I’d asked and can’t see any answers since.

First job of the season on Saturday so took it all out today. It’s been carefully stored in a heated garage. Oiled and WD40 beforehand etc.

Took it out today to run in advance of the job. Had same issue as in my original post. Not sucking water. Back-filled with hose until it came out the relief valve. Restarted and water coming out of hose but a bit sporadic. Fitted a nozzle and after a few spurts then off we go. All good from then on.

Am I missing something. Is it normal? And does the pump draw better when a nozzle is fitted. Could be coincidence but seemed to be the thing that made the most obvious difference.

Anything I can do or that I’m not doing to help the first start I only even worry about it as the first few times I used it last year it started, spurted out of relief valve straight away and then all good from then on.

It could be the pump is dry and isn’t sucking , we occasionally have the same issue we just put a garden hose onto the pump inlet turn the tap on and start the engine it then primes fine .

 

[Pjj]

Yes they are self priming but can get dry seals causing it not to draw water initially

 

[Truckcab79]

It could be the pump is dry and isn’t sucking , we occasionally have the same issue we just put a garden hose onto the pump inlet turn the tap on and start the engine it then primes fine .

Basically what I did. Seemed to work.
Anything I can do or is this ‘normal’


Totally different topic but not worth starting a new thread for. I should have some spare nozzles for my FSC but hadn’t got round to it. Current ones are marked 25025. They work fine and came with the Jetmac package so I assume they’re matched fine. I’ve not had any issue with them anyway. Is that the same thing as any 1/4bsp 25° nozzle?

And many thanks for the advice. So no harm by letting it run? Just stuff the hose in and wait for it to run out the relief valve?

 

[Pjj]

Basically what I did. Seemed to work.
Anything I can do or is this ‘normal’


Totally different topic but not worth starting a new thread for. I should have some spare nozzles for my FSC but hadn’t got round to it. Current ones are marked 25025. They work fine and came with the Jetmac package so I assume they’re matched fine. I’ve not had any issue with them anyway. Is that the same thing as any 1/4bsp 25° nozzle?

And many thanks for the advice. So no harm by letting it run? Just stuff the hose in and wait for it to run out the relief valve?

You don’t want to run the pump without water for to long if it doesn’t prime after a Minuit or two we put garden hose on it , it doesn’t happen very often with us , but usually after it’s been sat in the garage over winter and not used . Not sure about the jets there is a formula for working it out but cannot remember what it is ??? I just phone Ben at Rutland and order a few at a time , to be fair we don’t do that much pw to need replacing them that often

 

[Truckcab79]

You don’t want to run the pump without water for to long if it doesn’t prime after a Minuit or two we put garden hose on it , it doesn’t happen very often with us , but usually after it’s been sat in the garage over winter and not used . Not sure about the jets there is a formula for working it out but cannot remember what it is ??? I just phone Ben at Rutland and order a few at a time , to be fair we don’t do that much pw to need replacing them that often

Cheers. I had mine on for seconds each time before I panicked. Probably been spoiled because from new it always pumped through immediately. No doubt I was part of the problem.

Definitely haven’t worn my nozzles out ? Only got 10hrs on the machine since new and that’s FSC/turbo/rinse. Just think I should have a spare set on the off-chance I get a blockage.

Thanks again.

 

[ched999uk]

I think the jet code is orifice size and angle - unfortunately I don't know which part is which from the 25025. You might be able to work it out though. If your rinse and turbo came as part of the package they will probably have a bigger orifice (i.e. fsc has 2 jets so splits water via 2 nozzles) these should be marked as well.
To be sure best to speak to Rutland.

 

[Truckcab79]

I think the jet code is orifice size and angle - unfortunately I don't know which part is which from the 25025. You might be able to work it out though. If your rinse and turbo came as part of the package they will probably have a bigger orifice (i.e. fsc has 2 jets so splits water via 2 nozzles) these should be marked as well.
To be sure best to speak to Rutland.

Cheers. Had a look online and at the Jetmac site and it would appear that the number is 25 for 25° fan and 025 for orifice size so I’ll probably just order a stainless set off equip2Clean or someone else on eBay to avoid everyone’s minimum postage charges.