American Bristol problems

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I got a drain plug installed (will get a 5000psi drain valve later), found synthetic oil for it, found a suitable flywheel belt, and measured some fittings on the back which appear to be British Standard BSPT.

Bought a $15 2" 2000psi gauge to measure interstage pressure if needed later, but I'll have to order a compression fitting to connect 1/4"NPT male gauge to the 1/8: copper tubing.

Will buy a $15 2" 5000psi gauge to measure output final pressure, and run compressor tomorrow.

Windyairman, below is a photo of the 1/'8"copper I mentioned.

Frogman62, I think the compressor final output port is 1/4"NPT and I can connect a 5000psi gauge tomorrow. Can you give me more info on the military canister-style filter you mentioned, like what (Grade D?) air quality it produces, or if I can refill it myself or order replacement filters. I'll buy that as long as I can get replacement filters/refill it somewhere. I checked High Pressure Air Compressors - North Shore Compressor - Home which is not far, and they might have the filters.
 

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Batt. The moisture drain fitting does not need a high pressure valve. I use a 1/4 in ball valve from the hardware store that costs about $10. Max pressure is less than 300psi.
Save the 1/8 copper tube and fittings shown in your picture, don't cut them off, just crimp the end of the tube so you retain as much of the length as possible.
I can send pictures to you attached to an email. email address?? I have filter cartridges inside the filters which can be repacked and also some new canisters which you can use then modify slightly and make them repackable. With both the moisture separator and filter you will get grade E air purification.
Explain what fitting on the back of the compressor you are trying to measure ? I don't know of any fittings that need anything attached to them.
Jim
 
Finally got the compressor, engine, v-belt setup. On the very last piece of metal I cut, I found my hacksaw blade was very dull and I could've saved a lot of time by replacing it earlier!

Will start compressor with nothing connected to air output, in the morning.

Snowblower in the photo not included ;) Sorry the photos are blurry, either its too dark at night, my hands are shaking in excitement!
 

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I ran the Bristol compressor and connected T-fitting with valve and gauge, reached 3000psi. Then air started leaking and tightened:
-the compression fitting going to one 1/8" copper, used teflon tape
-the allen key screws on top valve cover
-crimped all 1/8" copper shut in two spots per pipe, one end was leaking

Now hit 3200psi, sped up to 2500rpm and 3500psi. Past 3200psi another loud air leak from same area on top. Looks like 1/8" compression fittings.

Drained the water valve, seems to be pretty oily water. All the oil I can see is the new Synthetic 20W50 I put in there, no trace of the black stuff it was shipped with so that must have been a very small amount of residue old oil inside.

This weekend I will:
-hold a tube up to my ear and three 1/8" compression fittings for leaks
-Change gauge, stuck at 2000psi when its not in use. I wonder if its really showing 5200psi max because of this problem.
 
Had some big personal probs last few weeks, didn't proceed with compressor retest yet. Maybe tomorrow.
 
Jim and Avi -

It has been a while since I've been in a position to ask for some help. The compressor is stored at my father in law's house, seeing as I live in a dinky townhouse and we always play at my wife's father's house anyway that was the best location. So every weekend I make it down there, do a little more work to the compressor, realize I need another piece or a tool and it of course has to wait until the next weekend to find out it doesn't fit etc. So, it's a long process.

As mentioned, I have a new problem that I can use some help with.

I have all of the leaks that I can find stopped up, gauged up, tightened down or otherwise, not leaking. So I start up the compressor and it get cooking, I push up to 1000psi no problem, after that it takes a little longer but continues to increase. I get to about 1400-1500 and I hear a leak. I shut off the compressor and find the source to be what looks like a blow off or safety valve. 1400psi is etched in the valve so I figure it's doing it's job by letting the pressure off. If I push on the top of the valve I can get a couple extra psi out of the compressor, but know that I shouldn't be doing that as the valve is there for a reason.

I have installed paintball gauges in the places where the copper tubes once were. I get about 40-60 psi on the 1st, about 300 on the 2nd and well over 1200 on the 3rd stage then my output gauge shows effectively the same output as the 3rd stage gauge (1200+ until the valve leaks). Which leads me to believe I have a issue with my 3rd stage.

Hopefully this information makes sense to you and will help diagnose the problem.

Also, could you describe how the compressor should run under normal conditions. Mine gets pretty hot as could be imagined, it smells like some dust gets burnt after running for a while, but I also hear some ticks and creaks after I shut it off, which I guess is normal also. I guess, just having no experience with these compressors, is there something I should watch out for, a tell tales sign or signs that would lead me to believe I have a problem, or something I can watch for that let's me know to shut it down immediately?

Last thing - I have a couple 3 way "L" kind of fittings that connect some of the guage lines. It seems like these are a fine thread flare fitting. I'm having a hard time find a 3/8" fine thread flare to 1/4" or 1/8" FPT, any idea where I might locate something like that?

Let me know if you have any questions. I am happy to answer them and my paintball buddies are ready to pump some HPA instead of just watch me work on this compressor all the time :)

Thanks.

Wes
wesval@yahoo.com
 
Sounds like a bad fourth stage valve. US flare fittings are pretty standard stuff, very orderly in terms of progression and thead count. No mysteries on this side of the pond as they are available from thousands of stores. Maybe you have some European stuff. If the T's are 1/4 inch pipe thread they could be replaced with US JIC type fittings from a hydraulic store.

Edit: disregard the above. After reading the description of the fittings for a second time I'm not sure what exactly is the problem. A three way fitting should be a "T", not an "L". I'm not sure what an FPT is. I have not heard of a fine thread flare fitting. I'm not sure if you are looking for an adapter, new T fittings or what. If FPT is some kind of pipe thread why would you want to attach a 3/8 tube (JIC 6) fitting to an 1/8 inch pipe? Is it a male pipe, like on a small gauge? Most of those big compressors use 1/4 inch NPT. One would attach a T fitting with one 1/4 male pipe and two JIC flare fittings for running tube. Are you trying to set up a bridging Tee between two tubes and running a third tube to a gauge? I kind of suspect that you want to screw a pipe thread tee into the head and this would have two different size flare fittings coming off, one to patch into the compressor air flow and the second leg to hook up to a gauge. On the other hand, you report that interstage pressures are already being measured. I'll back off this one and defer to the Bristol experts.
 
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Wes, the third stage pressure of 1200 psi is close to being correct so the third stage inlet and exhaust are working. Now you need to look for a leak between the 3rd exhaust and the 4th stage inlet. If you can't find one anywhere, then possibly the 4 stage is bad OR the inlet valve is leaking OR the exhaust valve is leaking or the seal on the cylinder sleeve is leaking ---- or several other things may be a problem.
Is the pressure relief valve at the inlet of the 4thstage popping off? Have you tried back pressuring the outlet fitting on the 4 th stage to see if the exhaust valve is holding? should hold 3000psi with no pressure loss if it is good.
Describe the location of the 3way L fittings and the lines coming and going from them. then maybe I can help.
Jim
 
Jim -

What is the best way for me to inspect/test everything? I understand there is this stuff called snoop that helps find leaks in pneumatic systems. Is there another method you recommend.

I can't seem to find an external leak between the 3rd and 4th stage, however will look again this weekend. However the 3rd Stage Safety Valve is popping, I think that's what you mean when you say "Is the pressure relief valve at the inlet of the 4thstage popping off?" If that's not what you mean, please reference the part in the diagram in the manual so I can find it without getting confused :)

When you say back pressure does that mean you want me to hook up a 3000psi scuba tank to the output on the compressor and turn on the air and listen for a leak?

Is it safe for me to take off the entire 4th stage cylinder head and inspect it for damage or will I be damaging something in the process. If it's something I can do myself I'll tear it down this weekend and send pictures that may mean more to you than to me.

I looked up the 3 way "L" fitting in the manual, which I should have done prior to giving you incomplete information. It is the "Stem Tee Connector" item #84 in the diagrams in the manual and part number Y19502. It has a fitting that seems to match up pretty well with a 3/8" fine thread flare fitting at a hardware store. I was hoping you could let me know exactly what kind of fitting (JIC?, Flare, etc) it is so I could find a way to convert it to a 1/4" female pipe thread so I can hookup a gauge.

Sorry you have to do so much hand holding, I just don't want to do something that completely mangles the whole system. I'm pretty capable when it comes to dismantling and reassembling, I just don't want to get ahead of myself.

Thanks again for all you guidance.

Wes
 

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