Pumping

[prosportfan]

I have a hill mk3. It seems to work fine but I am a springer shooter who's dabbling in pcps. Why does the pump feel heavy when pulling it upward? Is it supposed to feel that way? When pushing down nothing seems hard till like the last 2-3 inches. Is that normal? I do about 40 pumps and take a time out as to not over heat it. In pumping up a urban from about 1500psi to 3000psi and it takes about 120 strokes. Is that normal. Thanks in advance

[RDB]

Really shouldn't feel that way. Sounds like it may need a teardown and cleaning. Little rubber balls for the intake could be cruddy. Possibly a rebuild, small green oring.

[prosportfan]

Really shouldn't feel that way. Sounds like it may need a teardown and cleaning. Little rubber balls for the intake could be cruddy. Possibly a rebuild, small green oring.

rod if possible could you explain that in a little more detail please.  I also was blessed with a rebuild kit. 

[Techie]

Jay, what you describe sounds perfectly normal to me.  This is exactly how my three pumps work.  I think the reason it feels hard to pull the pump handle up is because it is compressing air on the upstroke, since it is a mult-stage pump.  That is the first stage.  It then further compresses this compressed air on the downstroke.  The last part of the downstroke is hard because the air is the most compressed at that point.  It's not like a bicycle pump where the air is coming out of the hose the entire time you are moving the handle downward.  The air only comes out of the hose and into the gun in that last part of the downward handle stroke, because it needs to overcome the high pressure that is already in the gun.  You need to push it all the way down to fully compress the air.  If you don't you'll be pumping forever.

It sounds like there is nothing wrong with your pump!  Don't rebuild it!  You said it works fine.

[RDB]

I guess what's your definition of hard. Question, if you let go of the handle on the up stroke, does it want to return to the bottom of the stroke on its own?

[prosportfan]

I guess what's your definition of hard. Question, if you let go of the handle on the up stroke, does it want to return to the bottom of the stroke on its own?

No it doesn't. It stays up.

[prosportfan]

Good to know...thanks mike

[RDB]

It probably fine then Mike. My MK4 doesn't seem hard in that manner. On the up stroke your drawing in air. And there are little rubber check balls in there that need cleaning of lube on occasion. If they get gummy, they can make it draw a little harder. How old or much use does the pump have? The two hills ive owned rusted the main tube within two years. Wouldn't be a bad idea to just pull the main outer tube for inspection. Hill has tear down instructions on there site.

[prosportfan]

It probably fine then Mike. My MK4 doesn't seem hard in that manner. On the up stroke your drawing in air. And there are little rubber check balls in there that need cleaning of lube on occasion. If they get gummy, they can make it draw a little harder. How old or much use does the pump have? The two hills ive owned rusted the main tube within two years. Wouldn't be a bad idea to just pull the main outer tube for inspection. Hill has tear down instructions on there site.

Rod, it was given to me so i have no idea about it what so ever.  As i said before, someone even blessed me with a rebuild kit but I wouldn't even know where to start, lol

[rjp]

... In pumping up a urban from about 1500psi to 3000psi and it takes about 120 strokes. Is that normal. Thanks in advance

I am new to PCPs as well, and If I had to pump 120 strokes for each refill I think I would quickly lose interest. I bought the cheap Yong Heng compressor from day one.

Now that these 4500psi air compressors can be found for around 200 dollars I don't understand why anyone would choose to pump by hand other than to get some exercise.  Maybe for portability?

Some of the hand pumps (Hill) are even more expensive than this compressor, and others (Crosman) are in the 175 range. How are these still selling?

[RDB]

... In pumping up a urban from about 1500psi to 3000psi and it takes about 120 strokes. Is that normal. Thanks in advance


I missed that part above. And will stick to my original statement. I think the pump needs a going through.

If memory serves me. I believe it wouldn't take me a 140-150 pumps to take a 13ci ninja bottle from 1500 to 3000psi. An urban has nowhere near that volume. So no, i dont think its normal.

[Techie]

Some of the hand pumps (Hill) are even more expensive than this compressor, and others (Crosman) are in the 175 range. How are these still selling?

Because we are buying equal or superior pumps for $40 on ebay; not paying those high prices you mention.  I also don't want to draw a bucket of cooling water just to fill an airgun.  What a pain.  I also like the exercise. 

It has taken me 120 pumps to fill an airgun.  That's not unusual.  Of course I live at high elevation so I'm pumping less dense air.  Also, if you don't completely finish each pump, it will take a lot more pumps.

[prosportfan]

... In pumping up a urban from about 1500psi to 3000psi and it takes about 120 strokes. Is that normal. Thanks in advance

I am new to PCPs as well, and If I had to pump 120 strokes for each refill I think I would quickly lose interest. I bought the cheap Yong Heng compressor from day one.

Now that these 4500psi air compressors can be found for around 200 dollars I don't understand why anyone would choose to pump by hand other than to get some exercise.  Maybe for portability?

Some of the hand pumps (Hill) are even more expensive than this compressor, and others (Crosman) are in the 175 range. How are these still selling?

you're right brother but it was a gift and I been out of work for about 2 months now.  wish I had a tank or compressor though

[prosportfan]

Rod and Mike, I seen a video where some very husky guy only had to pump it (his urban) like 40 times to get it back to his desired fill which I cannot truly remember what it was.  I just started to pump again from about 1200psi and then remember i said earlier that it raised up about 2-3 inches, well this time it was like 4-5 inches and the closer I get to the 3000psi fill that distance shortens.  Also when I compress/push all the way down, if I let the pump go it will rise the 2-3 inches.  Dudes i am a total noob when it comes to the pcp thing.  all help is much appreciated

[superchikn]

Jay,
That's not right.  I have Yong Heng compressor which was down for a bit and I grabbed my pump to fill in in a pinch, haven't used it since I got the compressor.  It needs a cleaning again, already did it once.  It takes as much force to pull up as push down and If i let go the handle bounces back.
There are check valves in each stage, which when not functioning correctly do not allow the air pressure to progress forward and cause "back pressure".
It may be the rubber ball under the handle, or something else but I tore mine down a while ago due to this situation and simply cleaned it.  Fixed!  It is not difficult.

[makarov76]

I just bought one a few weeks ago’ I pull up and push down slowly’ all the way down till I feel the air move to the next stage sometimes there is a vacuum pulling up’ I just keep slowly pumping after one or two pumps I feel the pressure advancing through the stages’
It keeps slowly building up so I assume it’s just the air working through the pump stages as I also see how it flows through the gauge and the needle fluctuates’ far as I’m concerned mine is fine’ sounds like yours is too’
I just reread this’ kinda turned me on’🤣

[prosportfan]

Thanks fellas

[anti-squirrel]

My China-pump 4-stage handpump pumps exactly as described- a little resistance coming up, lots more resistance going down.  Still more efficient than my Benji pump.


When it comes to filling a PCP, anybody who gripes about handpumping only to 3000 brings a smile to my face.  I've pumped my PP700 up from 80 bar up to 200 14x times in a goodly number of sessions- enough to go through a 500-count tin of pellets.  And... I've refilled my Leshiy 6 times in one session.  That's handpumping to 270 bar and shooting until it drops to 85