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rtbcomp
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Back on topic. It occurs to me that the motor could be a Friday afternoon model or maybe optimistically rated and perhaps increasing the volume of the delivery pipe is the way to go.
This is a unit I cobbled together a while back,
You can see the copper delivery tube arranged in a serpentine configuration, this was done to increase the surface area to help cooling, but I guess it also helps the motor get going as well.
This is a unit I cobbled together a while back,
You can see the copper delivery tube arranged in a serpentine configuration, this was done to increase the surface area to help cooling, but I guess it also helps the motor get going as well.
Crazy !! There is bad quality rubber too though. What happens is, retail stores want rubber to sell as the quality option but they won't pay the price. So the cowboys supply rubbish, eastern european or chinese stuff. It's even marked with the proper specs which it doesn't even have a hope of conforming to.
rtbcomp
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I mentioned belt tension a couple of times.
That pump is made by the Westinghouse Brake & Signal Company.
http://www.mig-welding.co.uk/forum/showthread.php?t=8692 If I remember correctly I had a few motor issues in that thread too. Came down to a slack belt in the end.
That pump is made by the Westinghouse Brake & Signal Company.
http://www.mig-welding.co.uk/forum/showthread.php?t=8692 If I remember correctly I had a few motor issues in that thread too. Came down to a slack belt in the end.
Cret
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Belt tension seems quite taut but going on things like fan belts etc I wouldn't have thought too tight. Difficult to know without having the info on how much slack movement it should have along it etc.
Someone did suggest it might be loose and that if the motor slips it can then stall, but it doesn't remotely appear to be anywhere near what I'd consider as loose (or not tight enough). I wouldn't want to tighten it more than it needs to be as it will add wear to motor bearings etc.
Re' safety of the pop bottle, the pressure in it never rises above the 20 psi or so needed for the unloader to close, so I can't imagine it really being a big issue surely? It's not that I intend leaving it like this, but even if it somehow did burst would 20psi really be enough to cause some damage with a flexible material like the bottle is made of?
Someone did suggest it might be loose and that if the motor slips it can then stall, but it doesn't remotely appear to be anywhere near what I'd consider as loose (or not tight enough). I wouldn't want to tighten it more than it needs to be as it will add wear to motor bearings etc.
Re' safety of the pop bottle, the pressure in it never rises above the 20 psi or so needed for the unloader to close, so I can't imagine it really being a big issue surely? It's not that I intend leaving it like this, but even if it somehow did burst would 20psi really be enough to cause some damage with a flexible material like the bottle is made of?
Cret
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The same logic occurred to me too about pressure.
But as it was running and increasing tank pressure, the pressure in the unloader line where the bottle is was staying static once it reached 20psi (or whatever it actually is) even though the tank pressure was increasing.
I'm sure the gauge isn't faulty, but then why would it not be increasing when the tank pressure is?
But as it was running and increasing tank pressure, the pressure in the unloader line where the bottle is was staying static once it reached 20psi (or whatever it actually is) even though the tank pressure was increasing.
I'm sure the gauge isn't faulty, but then why would it not be increasing when the tank pressure is?
Cret
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Fair enough. Thought someone suggested earlier it needed to be that sort of level but I might have been mistaken.
Will keep my eye open but in the meantime I'll be trying Sealey tech chap again. Didn't have a chance today though.
I don't think a length of hose would be sufficient volume really for this, unless it was shedloads of it coiled up or something.
Will keep my eye open but in the meantime I'll be trying Sealey tech chap again. Didn't have a chance today though.
I don't think a length of hose would be sufficient volume really for this, unless it was shedloads of it coiled up or something.
Cret
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True indeed. Would take a bit of experimentation to find the necessary volume for the compressor to work correctly I guess.
Done a bit of googling and the pressure that a plastic PET bottle can handle varies from brand to brand, and by size etc, but the most commonly touted figures seem to be about 80-200psi as a maximum. Now since the compressor has a cut off at I think 145psi these clearly would be a bit of a gamble to try using so I won't be running it up to any significant pressure with this attached!
I wonder what pressure a small fire extinguisher might typically hold (type you might have in a van or boat etc).
Done a bit of googling and the pressure that a plastic PET bottle can handle varies from brand to brand, and by size etc, but the most commonly touted figures seem to be about 80-200psi as a maximum. Now since the compressor has a cut off at I think 145psi these clearly would be a bit of a gamble to try using so I won't be running it up to any significant pressure with this attached!
I wonder what pressure a small fire extinguisher might typically hold (type you might have in a van or boat etc).
The discharge pipe does look rather short considering the compressor goes from standstill to 1636 rpm, or is supposed to in a matter of a few seconds, but it must be OK or Sealy would have had loads of recalls.
Have you had time to check the voltage at the motor whilst running, and with your new clamp meter around the start cap wire to see if the amp draw is dropping off every time it starts.
Just to re-cap here you have had or fitted
2 non return valves.
2 pressure switches.
2 run capacitors.
2 start capacitors.
Have you had time to check the voltage at the motor whilst running, and with your new clamp meter around the start cap wire to see if the amp draw is dropping off every time it starts.
Just to re-cap here you have had or fitted
2 non return valves.
2 pressure switches.
2 run capacitors.
2 start capacitors.
Cret
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Motor voltage (well, the voltage coming into the capacitor box which feeds the motor) starts at 240v and increases to 250v and stays there while running.
Not done those other tests though - will try to this evening.
Yes, I've replaced the check/non return valve (both looked absolutely fine when dismantled, although very very minor corrosion inside both).
I replaced the pressure switch temporarily with a different but compatible one and it made no difference (original is back on as it was better quality).
I have replaced both capacitors but now they've proven not to really help I will most likely refit the originals since they are a better physical fit.
Not done those other tests though - will try to this evening.
Yes, I've replaced the check/non return valve (both looked absolutely fine when dismantled, although very very minor corrosion inside both).
I replaced the pressure switch temporarily with a different but compatible one and it made no difference (original is back on as it was better quality).
I have replaced both capacitors but now they've proven not to really help I will most likely refit the originals since they are a better physical fit.
