Bristol Compressor

[Ianhw77k]

I recently picked up an old Bristol compressor with the intention of restoring it and using it to fill my 3L 300bar bottle. This won't be used for breathing air but it still needs to be kept clean as it will be filling my air rifle.
I could do with some help identifying the model and locating parts and manuals. Although I am a qualified mechanical engineer I spend most of my time on small engines so some tips on the inner workings of high pressure compressors would also be gratefully appreciated. I am well aware of the dangers of high pressure air but feel free to remind me or let me know if I am doing anything stupid. Here's some pictures.

 

[KD8NPB]

The aftercooler is in sorry shape. The valves likely need adjustment / replacement... maybe the piston rings too.

You will need to add a mechanical coalescer as well as a housing for a chemical dessicant to ensure clean, dry air. You can easily make your own chemical desiccant housing out of a hydraulic accumulator. The coalescer will run you about $600.

Your best match for this is probably going to be a little 15 hp horizontal shaft gas engine.

 

[Ianhw77k]

This is sounding expensive, luckily I didn't pay much more than scrap value for this unit.
If it turns out to be shot, would it be possible to run it as a lower pressure workshop compressor without too much hassle? Or is that not an option?

You'll have to excuse my ignorance, I'm good with engines but when it comes to compressors my knowledge is lacking. (I had to google mechanical coalescer:confused6

 

[CraigAClark]

You might try contacting Garner-Denver, as the bought out Hamworthy, which I believe was originally Bristol in the UK.

 

[frogman62]

It is a model 4S 7 5.2 CFM
I have manuals for the US models and I have extra cooling coils (not like yours) Look at my web site for the same U S model. Do you have the flywheel? I have 120 of these units
sheldensportinggoods.com
Jim Shelden

 

[Ianhw77k]

No flywheel/pulley, what you see is what you get I'm afraid.

Sounds like it was a nice idea but as more and more people look at it, it's looking less likely that this compressor will pump to 300bar ever again.
I might get the spanners out later today and see what the internals look like.

 

[frogman62]

Before you tear it all up, Do this
1. Remove all the cooling coils
2 remove the 4th stage completely. Do not take off the 4th stage head. Remove the 4 bolts from the 4 th stage where the 3rd and fourth stage join. This will allow you to look into the crank case and also look at the condition of the 4th stage piston.
3. IF the 4th stage piston will slide out the bottom of the complete 4th stage head and it is not frozen in place you may be in much better shape than you think. This model is the most reliable of all the Bristol /Hammworthy line.
4. After you have removed all the cooling coils take a couple more pictures and post them.

IF the results of this minor dis-assembly process is successful and things look good, I will sell you a flywheel and cooling coils for $200 plus freight.

IF you send me your real email address, I'll send you a electronic copy of the 4S7 manual - NO CHARGE my email is < jlshelden@sbcglobal.net >
Jim Shelden

 

[Ianhw77k]

Thanks Jim, shame I didn't read your post before I took the spanners to it.
I did take the fourth stage head off, it has quite a few shims in it (at least I think they are shims). I got it back on but I will need a manual or some guidance to make sure I did it right.
The piston looks OK to me but I could be wrong. It has 5 rings on it which I managed to get back in the bore without breaking.
The other pistons look good as well although I haven't gone as far as removing them as I presume that involves dismantling the bottom end.

Still waiting for pictures to upload which will probably take a while. It's getting a bit late over here so I will update the thread tomorrow.


EDIT: Photobucket album here:http://s1111.beta.photobucket.com/user/Ianhw77k/library/Bristol Compressor, I'll probably put some of the more interesting pictures on this thread tomorrow along with some observations and questions if anyone is interested.

 

[frogman62]

No they are not shims. They are springs for the intake valve. Before you tighten anything down and warp the valve plates and springs --carefiully read the manual and then if you have questions send me an email. Don't screw it up. Get those finned tubing removed so I can see the connections where they attach to the block. DON'T remove the valves on the sides of the block, as they are hard to reseal and probably fine based on the looks of the rest of the compressor insides.
Jim
Jim