Little 3hp not right

[lexi]

I have a cheap Jawel 3hp. About 2yrs old. It will only half fill the tank and I only get about 30psi max at the gun.

Won't fill up and knock off to standby.

Changed the oil. Funny thing is it dont' seem to be producing any water. None to drain out bottom and none in separator. No stange noises and no overheating. You can spray away with it but it runs continuously.

I got about 4yrs out my last cheap 3hp.................a special from Bambi.

 

[the snooper]

i think you will need to remove the cylinder head and check the reed valves they may be dirty and maybe the non return valve at the cylinder end of the delivery tube

 

[lexi]

Just looking for rusty gunge in non return valve then?

 

[the snooper]

it is possible that they have paint or similar on them ive even seen them broken.
quite often people have the compressor in the same area they are painting in so it sucks up the overspray which in turns sticks to the reeds and stops them sealing

 

[rtbcomp]

Is the relief valve in the pressure switch leaking? If so you'll hear a continuous hissing and you should be able to feel the air exiting below the switch unit.

 

[shenion]

Check the head bolts to see if they are loose. Don't overtighten them as you'll strip the aluminum.

 

[tigler]

Have a look at the air filter, will give an idea of what it's been inhaling !

 

[lexi]

Thanks for all answers. Air filters slightly choked with paint. Scraped it off till I get some new ones. Head bolts nipped up .........some were not tight.

Reed valves showed some paint on them but don't think they were sticking. Cleaned them up along with seatings.

I now get compressor to just under 60 psi. It still wont switch off. No air from valves or below switch unit. Only air I can feel is from motor itself and from the hole on the oil filler plug.

When switched off manually there is no escape of air anywhere. I finally was able to drain some water from tank.............previouslt nothing was there.

 

[rtbcomp]

Not sure about this one - would be OK to introduce a small amount of oil into the inlet to see if it seals the rings? If so you should see the pressure rise and the blow-by coming out of the filler hole should reduce.

 

[tigler]

Try it without the air filters to check if they are restricting the intake. In my experience once they have paint in them they are impossible to clean.

 

[langy]

Agreed, I have this T shirt

Try it without the air filters to check if they are restricting the intake. In my experience once they have paint in them they are impossible to clean.

 

[lexi]

Ok . air filters off.

Guys: One cylinder is sucking and other is blowing.


Does this mean I have a two stroke compressor

 

[eil]

Head gasket gone between the cyls?.

 

[rtbcomp]

Do the valves & seats come out together - ie could you have got them mixed up on the cylinder that's blowing?

 

[lexi]

Two valves per cylinder. Reeds are oval shaped and sit in the machined part of the head.

Do they have an inversion on them or are they completely flat?

Will strip it again and take a pic.

Come to think of it : When I stripped air filters at first I noticed a dent on the inside of one housing. This is where it had been blowing out air. That filter was nowhwere near as dirty. The other has been doing all the sucking.

 

[rtbcomp]

From the one I stripped down the valves were flat discs. The inlet sat flush within a machined recess in the head and was held in place with a spider and a light spring to hold it closed.

The outlet was slightly more complicated in that it had to seal in a removeable housing, held closed by its own weight.

 

[lexi]

Put it back together and started up. At first both cylinders were sucking nicely. After 30 secs the suspect cylinder started blowing at the air inlet.

I give up. It goes to around 60 psi on the gauge and still does not switch off. It will have to do for the moment.

I still managed to paint the ser11 with it. Along with all other work it has paid for itself. I use the adjective " paint" loosely

I will see if Jawel have gaskets and maybe renew them. There is a metal and two composite ones which are quite thick. Yeah I said I would give up but ya never do ya ?

 

[eil]

On some compressors you will have a valve plate which houses the reeds/valves them selfs so you would have two head gaskets in a way, one underneath the valve plate and one on top between the plate and head, don't know what type you've got but that symptom is one I have experienced and the gasket on mine had gone underneath the valve plate, its either that or the reeds, is it possible to swap them over to prove a point.

 

[lexi]

Thanks Eil. will try that. You are bang on with gaskets. On each head there are two composite ones and a metal one between them. All the reeds look intact and identical. They are seated the same and I had to use a tiny spot of silicone grease to keep them in situ. The bottom gaskets I have not looked at .......they tend to destruct if removed so I will try for new ones.

Just looked on Jawel site and they no longer have that compressor. Will get some gasket material and make a few up. It looks like thick vinyl paper.