compressor head gasket

[scarecrow]

its blowing out into the intake and not building pressure

 

[the snooper]

in that case it sounds like the bit you have missing is the culprit

 

[scarecrow]

in that case it sounds like the bit you have missing is the culprit

thats what im afraid of the strip between the valve is quite narrow so will need to be strong cant see a paper gasket surviving there

 

[the snooper]

you could try a cardboard gasket just as a test then source some ally and cut one out

 

[eil]

Have you put the reeds back in the same place they came from, as the reeds can be slightly curved and not flat as you say, get them the wrong way round and they wont seal properly.

 

[scarecrow]

I replaced all three gaskets with the paper ones and it has improved things but not 100%
when the compressor cuts out you can hear it hissing through the air intake till the pressure in the cylinders drop but at least it's building up pressure so not a major leak it could be either one of the two top gaskets or the valves. but my money's on one of the gaskets
the reeds are perfectly flat the recess that they fit into is curved







will I be able to get a sheet of Ally as thin as a sheet of tinfoil

 

[brightspark]

I replaced all three gaskets with the paper ones and it has improved things but not 100%
when the compressor cuts out you can hear it hissing through the air intake till the pressure in the cylinders drop but at least it's building up pressure so not a major leak it could be either one of the two top gaskets or the valves. but my money's on one of the gaskets
the reeds are perfectly flat the recess that they fit into is curved


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will I be able to get a sheet of Ally as thin as a sheet of tinfoil

tinfoil used to be made of tin. its now aluminium foil. u can get diffrent thicknesses of steel shim stock on a roll

 

[wyn]

For the valve you could try using some "shim stock" which would be available in a few different thicknesses.
The thiner stuff can probably be cut and punched like a gasket.


Brightspark was a bit quicker on the keyboard

 

[scarecrow]

where do i go looking for shim stock

 

[wyn]

You could try here or any sort of industrial supply place.

 

[brightspark]

where do i go looking for shim stock

most good engineering supplies should have it

 

[scarecrow]

will shim be compressible to make a seal or will i need gasket cement as well

 

[the snooper]

when the compressor cuts out you can hear it hissing through the air intake till the pressure in the cylinders drop

you shouldnt have any pressure left in the cylinders to hear as it should have been unloaded when it cut out

obviously your top gasket will have to be good or you will just recycle the compressed air you should be able to use copper for that gasket or any heat resisant material as the thickness isnt critical on that part .

i would also check that the unloading valve is working and possibly make sure that the one way valve on the cylinder is working and not letting air back to the pump

 

[rtbcomp]

If it's hissing with the motor stopped enough to allow the pressure in the tank to drop then the non-return valve (where the delivery pipe joins the tank) is leaking.

If you get a short burst of hiss when the pump stops the unloading valve in the switch is OK. It's held open anyway with the pressure switch "off".

 

[brightspark]

you shouldnt have any pressure left in the cylinders to hear as it should have been unloaded when it cut out

obviously your top gasket will have to be good or you will just recycle the compressed air you should be able to use copper for that gasket or any heat resisant material as the thickness isnt critical on that part .

i would also check that the unloading valve is working and possibly make sure that the one way valve on the cylinder is working and not letting air back to the pump

as said coppers ideal it can be anealed before fitting .ask a plumber . cut a piece out of a hot water cylinder

 

[pedrobedro]

I once made a head gasket for a moped from a silver foil fried rice tray. It was an obscure make and couldn't get parts for it but it worked fine after that.

 

[scarecrow]

cut a bit out of the hot water cylinder and the top of a muller rice and bob your uncle im starting to fieel like McGivor

I had checked the non-return valve and it seemed okay the hissing only last for about 10 seconds and it's definitely coming out of the air intake so there might be a problem with the dumb valve
a copper gasket for the top chamber sounds like the business I might try some silver foil for the valve gasket I'm just waiting to get gasket cement I know I wont be able to put to much on the valve gasket in case it gets onto valve

 

[rtbcomp]

....
I had checked the non-return valve and it seemed okay the hissing only last for about 10 seconds and it's definitely coming out of the air intake so there might be a problem with the dumb valve
.....

Do you get a brief loud hiss from the pressure switch when the motor stops? If so the dump valve is OK.

Once the cylinder and delivery pipe are empty any air leaking out of the inlet must be coming from the tank via the non-return valve. It should also exit from the dump valve as long as the motor switch is held off (Either by pressure in the tank or the control knob).

 

[the snooper]

10 seconds is a long time for it to hiss, if the dump valve isnt working then the hissing could be from the top gasket or it could mean that the inlet reed valve is leaking ie
pressure in the delivery pipe will also mean there is still pressure in the cylinder and could be leaking back past the inlet valve so dont write off the gaskets you have made i would inspect the valves and thier seats to make sure they are spotless

 

[scarecrow]

the pipe to the dump valve was blocked just need to get some compound and seal the gaskets as its taking a lot longer to pump up
im wonder if them paper gasket will stand up to the heat