Clarke compressor cutting out

[Maddog]

Hi guys,

Not been here for a very long time.
I've just moved house and rewired in my compressor. It's a clarke 3hp 150 belt drive jobbie.

It's hard wired through a switch to the main RCD in the garage into a 30a mcb which is how it was done at my old house, however when I first moved I used it just fine once. Came to it the other day and the reset button on it is tripping out after just running for a few seconds.

None of the circuit breakers are popping so all seems good there.
The only thing that I did do was drain the water from ths tank and accidentally left the tap open. Can't really see that be a problem though. Anyone have any ideas?

Thanks in advance.

Andy.

 

[the snooper]

could do to check what amperage its drawing which would show if the cut out is at fault or it is drawing more power then it should, is it getting upto speed before it trips

 

[anjum]

Just try replacing the cut out or bypassing it with a fuse, see if it stay running.

 

[rtbcomp]

If it's not getting up to speed and you've just moved it:

1) check belt tension

2) is it in a colder location than it was before?

 

[Ton-up]

What breaker is it on? Is the cut out switch on the motor terminal cover? if so they are crap. If you don't have a clamp-meter, I would take the cover off and rewire it to bypass the cutout. Make sure the mcb is properly rated to protect the motor.This will prove whether the cutout is 'weak' or not.

 

[Maddog]

Thanks guys. I've just had a mate (qualified electrician) rewire my whole garage with 50a armoured from the house.
The main breaker in the garage has a 30a mcb for the compressor and is brand new.

It's no colder where I live as I've only moved a mile up the road.

In order to test the reset switch on the compressor can i just disconnect the trip switch and wire some heavy cable across the spade connectors that connected it to the switch?

Also if the belt was loose wouldn't the compressor still run just wouldn't pressurise properly?

Thanks.

 

[Ton-up]

Yes, belt slipping would probably not matter.
Does it actually run or try to turn but then trip?
Just join the two spades like you said. Has it a capacitor or two? If it does not try to turn have a look at the capacitor.
30 amp seeems a bit big for a 3 horse motor.

 

[Maddog]

Thanks guys.

It starts up (it has a soft start) and after few seconds as it gets faster then it trips out the switch.
If it is the oil that needs changing does it have a drain plug or anything? Or even a filter?
Thanks.

 

[Maddog]

Hi guys.

Tried it with a nail in place of the reset switch. Worked fine and nothing seemed to pop.
Looks like a duff reset switch then? It's rated at 15a.

Cheers.

 

[Maddog]

Right guys, replaced the motor reset button today and it's only popped once so far BUT the motor/pump is very slow to start.
It barely turns at all and very slowly increases RPM until it's up to full chat.

Any ideas? It is quite cold today (around 3 degrees celcius) So I guess the oil is thick but jeez, it's like it's trying to turn over in treacle. I'll change the oil soon (how much do they hold) anything else it could be?

Thanks.

 

[WorkshopChris]

Is the motor getting up to speed almost instantly with the belts removed?

 

[roofman]

ime going with a duff start capacitor

 

[dobbslc]

Also is it still slow to start once it's warmed up for a few minutes?
Once the oils been warmed up for a few minutes it should be ok after.

 

[roofman]

I really cant see it being oil...the oil is not pumped but flicked by a thin finger hanging down from the bottom of the conrod,the drag off this must be hardly meaurable

 

[roofman]

Fair point but explain why this forum every winter gets the same "my compressor won't start" "turns very slowly" etc at the first signs of cold, and then again during cold snaps, yet never in summer?

I dont have a clue Fuzzy...maybe the electric is thicker in the winter and wont go down the wires fast enough

 

[brightspark]

most modern machines are just on the mark power wise so cold weather isn't going to help .as I said in another post my 90cfm comp I had with a twin lister engine running it I couldn't crank it over in winter without warming over it with a blowtorch but in summer it was easy to crank so its not rocket science to work out there's more drag when cold .as in motor less starting torque

 

[Maddog]

Thanks for all the responses guys.

It is now getting up to speed eventually so I ran it for a couple of minutes to get warm then switched off and tried again. And it was slower than ever.. barely even turning.

It's tricky job to remove the belt as I'll need to move the compressor to do so (and she's a heavy girl) maybe I should try the capacitor (s) which one will it be or do I need to try both? There is a blue one and I can't recall the other one.

Thanks.

 

[the snooper]

is the unloader valve working ie does it hiss when you turn it off and when it reaches pressure and will it start better when the receiver is empty

 

[Maddog]

Hi mate, the unloader valve is working fine, when you stop the motor it hisses briefly as it should.

The model number is something like a Clarke SE15C150 (maybe an SE16) it's a single phase 150 litre tank.

Bit like the one below but the motor is on the right hand side with the belt at the back.

https://www.machinemart.co.uk/p/se15c150-ol-air-compressor/

Thanks.

 

[Maddog]

Great. Thanks mate, I'll give that a go.