Fill rate slowing down

[paddydiver]

MY Coltri Mch6 has about 60 hours on it and the fill rate seems to be slowing down quite a bit over the last few fills. I use it lightly. Normally only filling 1 tank (or 1 twin set) per fill, 10l 12l or double 10's per use. Filter and oil are changed regularly, a little more often then recommended by the manual.

Before I go looking at it myself is their any pointers from more experienced people on here? Maybe the belt needs tightening? Anything else I should be looking at? It's not a dramatic slow down, but definitely slower then it was.

 

[rjack321]

Third cylinder ring blow by. Basically it's a super cheap compressor and not expected to last.

 

[paddydiver]

.....It's expected to last more the 60 hrs!

 

[Edward3c]

MY Coltri Mch6 has about 60 hours on it and the fill rate seems to be slowing down quite a bit over the last few fills. I use it lightly. Normally only filling 1 tank (or 1 twin set) per fill, 10l 12l or double 10's per use. Filter and oil are changed regularly, a little more often then recommended by the manual.

Before I go looking at it myself is their any pointers from more experienced people on here? Maybe the belt needs tightening? Anything else I should be looking at? It's not a dramatic slow down, but definitely slower then it was.

I’ve got over 140 hours and 400 fills and still getting the same fill times. And pump to 300bar.

 

[paddydiver]

It's down by a matter of minutes over the last few fills. Cylinders usually have at least 50 or 60 bar in them, fills fine up to about 150 bar then slows down more then it used to get up to 220.

 

[Edward3c]

I did experience this, but it turned out to be the gauge needle sticking as when it got to 260 bar it would jump up; I changed the gauge that fixed it.

 

[Wallowa]

.....It's expected to last more the 60 hrs!

Check with soap solution for leaks on fill hose fittings...nothing then try other fittings...not certin how air temp and humidity would change compression rate, if at all...

 

[iain/hsm]

MY Coltri Mch6 has about 60 hours on it and the fill rate sems to be slowing down quite a bit over the last few fills.

From what you're saying I would suspect this is either a much older model MCH-6 or it's ran for considerably longer than 60 hours. What you describe are typical symptoms of old age same as us I guess as we get older we get slower then we need more maintenance, then we break down then we die. Compressors are normally no different albeit the MCH-6 is well known as a short cycle life recreational sports product however for the minimum filling your doing I would not expect these symptoms in such a short run time.

The engineers quick cheap check (for blow by) on a Coltri MCH-6 is run the pump up until you reach the flow decline usually over the BPR setting (if you have one fitted) and take out the oil dip stick while running and stick your finger over the hole if you can feel gas escaping from the crank its a good pay day for him. Now by contrast if you had a Bauer equivalent the Junior 2 it would be three times the age of your Coltri and with much more hours on the clock and the engineer would use a flow meter and measure the blow-By flow rate against the pressure over BPR every 500psi over 1500 to the maximum discharge pressure for the pump.

But although the symptom you describe is of blow-by hence the finger on the trigger test.
If it passes this at the point it slows down in flow rate. Then it's down to the next possible fault on my many listed fault items for the MCH-6 fault finding process.

Maybe the belt needs tightening? Anything else I should be looking at? It's not a dramatic slow down, but definitely slower then it was.

Again hardly at 60 hours unless you've changed the motor over or especially if you or others had changed out from a petrol (gas) engine to electric. But that would give a low flow from the get go. So not on my symptom fault tree list. Belt slippage due to wear I would expect to add a zero to your 60 hours. But you do need to check belt tension quite often on the MCH-6 say every couple of months.

 

[iain/hsm]

I’ve got over 140 hours and 400 fills and still getting the same fill times. And pump to 300bar.

Just exactly what were you thinking with that reply above and how does it help ?

"Any more than You've done one fill a week for the last ten years topping up your air gun" ROFL

 

[iain/hsm]

Check with soap solution for leaks on fill hose fittings...nothing then try other fittings...

Heck another thick and fast wild ass guess tonight from the Coltri Fan Boys Club.
Good idea if the OP was asking how to clean his compressor I guess but that wasn't the question or the solution for the symptom. However a cleaner less messy way to check for leaks on the MCH-6 is to run it up to full pressure and switch power off and wait.
Assuming your not deaf that is.

not certin how air temp and humidity would change compression rate, if at all...

If you're not certain ROFL. Then neither am I.
But the kicker is how the heck you came up with nonsense idea in the first place
Did someone remove a post questioning air temp and humidity then the answer would have been the relationship between P1 V1 over T1 equating to P2 V2 over T2 during the compression process and then it certainly would have an effect. Just not if at all I guess.
8/10 for effort.

Any advise on what brand of soap we should use