Compressor just packed up

[rcx132]

My bargain compressor that I got for £100 has just packed up. I only noticed just before leaving the workshop so I couldn't look at it much. The motor was spinning but the pump was cold despite the crank on the pump turning! Explains why I wasn't getting much air, my second compressor was doing all the work alone.

If the pump is worn then it would still pump a bit right and maybe get a bit hot? Could some valve have got stuck? It's a Clarke compressor, if it's worn, are replacement pistons and parts available?

I'm off to Scunthorpe tomorrow to pick up my new Suzuki Samurai (next project), so I can open up the pump on Friday.

 

[Hood]

Had exactly the same happen, took the head off, saw nothing amiss, was expecting to see dirt under the valves. Took them apart anyway just in case but never saw anything, made new gaskets out of cardboard and put it back together and it has been working fine for the last 6 months. It is a clarke as well.

 

[rtbcomp]

Is it belt driven or direct drive?

 

[rcx132]

Is it belt driven or direct drive?

Belt drive. 150 litre 4 hp Clarke industrial.

 

[rcx132]

Removed pump, head off.... Problem found immediately. The valve springs are broken. Both are broken though and I can't find the broken off bit from one of the valves. I don't get how the both broke at once, if one valve breaks then I don'tt hink the pump would work because pressure would transfer to the second cylinder as they share ports. New parts on way from Clarke.

 

[Hood]

Strange you can't find the valve spring unless the previous owner had been in and removed it then as it was half working just sold it on?

 

[Bill Edwards]

Either blown into the air filter or gone down the air delivery pipe seem like the only possibilities to me. I'd probably be looking to see if it's at the check valve myself.
In fact, as of yesterday I replaced (made) a spring for a compressor. Sometimes when it starts it builds pressure before the tank and stalls within a few seconds, blocking at the check valve into the tank. Must be a piece of the broken valve jammed somewhere I think.

 

[rcx132]

Fond the second broken valve in the aftercooler! Thanks for the tip to look there

 

[rcx132]

And now the bugger is overheating! Opened up the pump again, I can't see anything amiss :/
Going to phone Clarke, but ideas for what to look for?

When I opened the pump the head bolts were loose, assume due to the heat. I had torqued them using generic torque settings (25 Nm as they are M8 bolts). And the gasket has blown, letting air out the head. I cut my own gaskets out of 0.8mm gasket paper.

 

[rtbcomp]

...
When I opened the pump the head bolts were loose, assume due to the heat. I had torqued them using generic torque settings (25 Nm as they are M8 bolts). And the gasket has blown, letting air out the head. I cut my own gaskets out of 0.8mm gasket paper.

Was this the first or second time you opened it up? How long did it run before overheating? What makes you say it was overheating? - it's quite easy to burn yourself on the delivery pipe.

 

[rcx132]

Was this the first or second time you opened it up? How long did it run before overheating? What makes you say it was overheating? - it's quite easy to burn yourself on the delivery pipe.

New valve leaves fitted, head fitted using home cut gaskets, and head bolts torqued to 23 Nm. I ran the compressor for 20 min while blasting at 90 psi. I then heard hissing. Switched off compressor. Notice gasket is blown. Removed pump. Undid head bolts... head bolts are loose. Remove cylinder... all looks good.

Aside from the fact that I've used home cut gaskets and that one of the home cut gaskets blew, all looks good. Waiting for Clarke to call me back with torque settings for head bolts and advice.

Little upset as each time I make progress something like this happens and my day disappears :/ Having to go back to work now so will have far less garage time.

 

[rcx132]

Clarke just phoned up, the guy was a bit dopey. Gave me torque setting (35 Nm so I was well under), and said the blown gasket could be what caused over heating.

 

[rtbcomp]

Was the gasket you used any thinner than the original? If so you may have been tightening down on the end of the thread rather than the head. Maybe put some washers under the nuts to make sure.

I'd use proper heat resistant gasket material, annealed copper sheet is best, but there are modern composites available.

 

[rcx132]

Was the gasket you used any thinner than the original? If so you may have been tightening down on the end of the thread rather than the head. Maybe put some washers under the nuts to make sure.

I'd use proper heat resistant gasket material, annealed copper sheet is best, but there are modern composites available.

Thanks I will put in a better gasket like you say.

For now it's working, no more over heating, so maybe it was the blown gasket, which blew due to the low torque settings.

 

[rtbcomp]

Fingers crossed

 

[normspanners]

Havnt read all this no time, but ahead gasket usually causes overheating I repaired one using copper for the head gaskets, instead of the fibre one it is the bridge piece that blows out, so I made the bridge piece wider but only on the inlet side a portion of the gasket in the free cooler air on the inlet side of the head, this keeps that bridge piece cooler and stronger and less likely to blow out, as the compressor is still working fine 6years later, when it had had 3 new pumps in 2yrs and is really being over worked ie over its duty cycle but it now runs faultlessly that seems to be the answer.