Benjamin Hand Pump Maintenance, Modifications and Reliability

[bubba zanetti]

This was discussed at length on the Marauder Forum. Will it work? Sounds like it will, but I prefer the 100% silicone oil. Using 15wt. by the way. As a side note, I may buy a bottle of 30 wt. BTB or go with the gear oil RC stuff.

I am not a metallurgist or lubrication guru (except in the bedroom  ), but I have learned in life to follow the advise of those 'in the know'. Tuners and the hardcore crowd usually make discoveries the lay person does not or will not. The two points on the M-Rod forum were put a desiccant filter on your Benji pump and use 100% silicone oil (the shock oil form hobby stores) as the lube. When I called Sun Optics and ordered two rebuild kits, the very nice lady asked what I would be using as lube and I read her the bottle. Know what she said? "Perfect! That RC shock oil works really well for these pumps and you don't need much".

Those are my thoughts 

BZ

[45Bravo]

I have plenty of silicone oil in different weights from my rc days, and am still using it on my airsoft guns (yes I consider them airguns too)

I just thought it was interesting..

[bubba zanetti]

I have plenty of silicone oil in different weights from my rc days, and am still using it on my airsoft guns (yes I consider them airguns too)

I just thought it was interesting..

I agree and hope my post did not come off the wrong way Bravo.

Will the Mobil 1 work? Probably work great, but the silicone oil is proven so lets lube it up! 

BZ

[Tommy]

I just have to say that if you look hard enough you can find a tank set up for the price of a pump.I got a tank with fresh hydro {80cf 3000 psi] for $50 and bought the fill system from PA for $100 Fills cost me $6 and I get 80 fills from 1000psi to 2000psi. I had to have patience on the tank but alot of research and phone calls and I ended up with a few choices up to $75 for the tank. I shoot every day and could not imagine not having a tank.
Tommy

[BigTinBoat]

I just have to say that if you look hard enough you can find a tank set up for the price of a pump.I got a tank with fresh hydro {80cf 3000 psi] for $50 and bought the fill system from PA for $100 Fills cost me $6 and I get 80 fills from 1000psi to 2000psi. I had to have patience on the tank but alot of research and phone calls and I ended up with a few choices up to $75 for the tank. I shoot every day and could not imagine not having a tank.
Tommy

Most 80cf tanks with current Hydro are somewhere between $150 and $200. Around my way even ones out of Hydro are going for $75.
Then once you add the $6 per fill, plus the gas in your vehicle to get it to fill station (I'm guessing it would be a job carrying an 80cf tank while walking) along with the other expenses on your vehicle, not to mention the fact that you have to go and get it filled when they are open. I see this as inconvenient to say the least. Plus what would I do with my gun while I'm waiting to find a $50 tank deal?

If we base the decision on what you happened to get a tank for, sure it seems like a great deal. I just picked up an Air Venturi hand pump for $29 (Shipped) from ebay. It was under a $1 for the O-rings needed to have it pumping. So now I have a pretty much unlimited source of air for $30.

[bubba zanetti]

Tommy:

Appreciate the info and trust me, I do keep an eye out for a nice deal on a tank, but tanks are NOT what this thread is about or boosting a pump, etc.

There is a simple reality that many of us PCP owners don't mind pumping, are on a severe budget or don't want to buy a tank set up as they just don't want one or any other myriad of reasons that could be listed.

I have had the M-Rod filled by SCBA tank and it was very fast and nice during a  big pest hunt on a dairy farm. So I am aware of the convenience factor. I fully understand why fellow AG shooters purchase them and am not ignorant of their usefulness. With that said, one of the reasons I started this thread was the people on a budget or the person who saved for a DayState or FX or even a M-Rod, but can only afford a hand pump to fill it. The question comes in: How can I keep this thing reliable? How can I keep it working? Any simple mods help?

Nuff said

BZ

[45Bravo]

I was reading the manual for a friends FX pump, and it specifies a certain lube by name for the pump.
(The FX pumps also have a 5 year parts and labor warranty I am surprised to find out.)

The Benjamin is 90 days warranty.

But they suggest using RENOLIT-RHF1 (what ever that is)

But in researching the lube I found this.
http://www.ebay.com/itm/LQUID8R-FX-1-Synth-Grease-w-PTFE-Replaces-RENOLIT-RHF-Precharge-PCP-Airgun-Pumps-/271115044952


Also the FX has a moisture trap built into the base that is vented when you release the pressure.

[bubba zanetti]

But they suggest using RENOLIT-RHF1 (what ever that is)


Its Swedish for "100% silicone lube" 

BZ

[45Bravo]

You said it Bubba,
Truthfully, I don't mind pumping.

With the B50 at its current setting, I get 30 shots, and pump 26-30 times. (Depending if I bottom & top out the pump every stroke.)

It may sometimes be inconvenient (dusty environment) .
I just put a clean bath mat in the bed of my truck,
or on a bench at the range for the rifle and pump to to sit so they aren't in the dirt.

Definitely easier than 8 pumps on a Benjamin 392 per shot..

[bubba zanetti]

Here is the threads final update:

After pumping both my Bam-50 and .25 M-Rod multiple times I have come to the conclusion that the Benjamin pump works but does not like consistently pumping past 2500 psi. This range appears to be very hard on the pump. It can do it but this is when I had the most problems. So in no order:

Pros:
-Very easy pump to maintain, tear it down a few times and its a simple pump to repair.
-o rings are cheap for the pump.
-works very well for 2000 psi or under pumping.
-Price, if you can get one for under 100 bucks, makes a nice back up.
-If on a budget, it will fill your AG

Cons:
-Hard to pump over 2500 psi. Its work and this is when the pump o rings can be damaged.
-Have to carry spare o-rings and a couple adjustable wrenches to shoots or when shooting.
-At full price, not worth it for pumping guns to the 3000 psi mark.
-Have to modify it to keep moisture out (i.e. add desiccant filters)

The M-rod is what really made me decide to leave the Benjamin Pump. I burned up more o-rings going from 2500-3000 psi without really trying. I had to learn to pump really, really slow and methodical in this psi range. Too slow for my tastes. Also, when I would let others shoot the M-rod and pump the gun back up, it did not matter how many times I showed how to pump the m-rod they would fry o-rings and I would be pulling the pump apart in the field and rebuilding it. Again, thats really easy to do but with the M-rod tuned between 2000-3000 psi it was a PIA! So the Benji pump has moved to a new home. Another GTA member bought to for back up.

So what is Bubba Zanetti using now? I bought a HIll Pump from PA a few weeks ago with one of their Christmas special coupons. Got it shipped for 256.00. So far I have pumped the M-Rod and my little Ninja tank for the Drozd-both to 3000 psi. All I can say there is no comparison between the Benji pump and the Hill in the 2500 to 3000 fill range. The HIll does it so much faster and without the hard work. I do not have to lean on the Hill like I did the Benji to get that last 500 psi in. Also, the Hill defiantly moves MORE air into the M-Rod and Ninja tank so I am not pumping as long.

When people say "get a Hill and be down with it" I now know why. If you think you will be a pumper and you have HPA guns that are filled to 3000 psi, save your money for a tank or a HIll Pump. The HIll owners are right-there is just no comparison.

BZ

[airgunnertoo]

 few questions for those more knowledgeable than I. I disassembled my pump yesterday then cleaned and soaked it with some cerflon silicon spray it has set all night to dry. today I went to harbor freight to get the filter and was looking for plumbers grease well they didn't have any and I found super lube instead. will the super lube be ok to use with the silicon a sprayed on it yesterday, or will there be some kind of bad reaction?

 also the filter I have I just looked at it and not all beads are blue some most are purple and some look possibly pink. do I unscrew the big end to get them out?

 thank you.

[comemeer]

few questions for those more knowledgeable than I. I disassembled my pump yesterday then cleaned and soaked it with some cerflon silicon spray it has set all night to dry. today I went to harbor freight to get the filter and was looking for plumbers grease well they didn't have any and I found super lube instead. will the super lube be ok to use with the silicon a sprayed on it yesterday, or will there be some kind of bad reaction?

 also the filter I have I just looked at it and not all beads are blue some most are purple and some look possibly pink. do I unscrew the big end to get them out?

 thank you.

I installed one of those HF filters on my pump and used it for several months, but I honestly don’t believe it did any good at all. Each time I opened the bleed valve I could feel moisture on my hand.  Also, the silica beads never changed color the entire time I used the filter.  I would have expected them to turn pink but they remained the same blue color. I got rid of the HF filter and replaced it with one I made based on the information I found in this post (http://www.gatewaytoairguns.org/GTA/index.php?topic=42922.0).  I used silica based kitty litter as the desiccant.  Now I don’t notice any moisture when I open the bleed screw.
As far as silicone plumber’s grease… I have seen it for sale in the plumbing section of Lowes/Home Depot.

[nervoustrigger]

will the super lube be ok to use with the silicon a sprayed on it yesterday, or will there be some kind of bad reaction?

Super Lube is a good lubricant for this application.  I'm not familiar with the spray lubricant you mentioned but it's generally not advisable to mix lubricants.  Also, I wouldn't want to reassemble anything that has been sitting out for any length of time anyway, unless it was in stored an assembly clean room.  Any lubricant on the parts invites dust and contaminants to the exposed surfaces.  Start with clean parts and lubricate as you assemble.

[cwlongshot]

Morning guys,

 Dan I don't know how I missed this thread but thank you good info!

 I have a question. Early on someone mentions Sun Optics desiccant kit and I have seen it too.

But you reply Harbor Freight and NAPA have the filters cheaper... I assume for different applications.

Do you have a parts list for hardware required to add the bung to attach the filter as well as what filter to ask for or where to look to find one.

A tank is also on my list... I almost jumped on the MAC1 tiny bottle before I realized how small it is. Might be OK for the 1500 & 2000psi guns but not so much the thirsty Mrod 25. I think I need a larger bottle and really want a 4500 to make the most of my trips for refills...  That's another thread for another time.

Making my benji pump last and improve the quality of its performance is a good thing for now.

Thank you,
 CW

[bubba zanetti]

Morning guys,

 Dan I don't know how I missed this thread but thank you good info!

 I have a question. Early on someone mentions Sun Optics desiccant kit and I have seen it too.

But you reply Harbor Freight and NAPA have the filters cheaper... I assume for different applications.

Do you have a parts list for hardware required to add the bung to attach the filter as well as what filter to ask for or where to look to find one.

A tank is also on my list... I almost jumped on the MAC1 tiny bottle before I realized how small it is. Might be OK for the 1500 & 2000psi guns but not so much the thirsty Mrod 25. I think I need a larger bottle and really want a 4500 to make the most of my trips for refills...  That's another thread for another time.

Making my benji pump last and improve the quality of its performance is a good thing for now.

Thank you,
 CW

Brian:

I don't have a list. I took the pump base and the HF desiccant filter to ACE Hardware and picked out the brass fittings to connect the filter to the base. Trial and error and I dint write anything down as I figured that what everybody does LOL!. The HF filter is in their spray gun area, at least at my local HF.

If saving for a 4500 psi bottle then this may be irrelevant, but now having the Hill pump for a bit I am amazed at how much easier the last 500 psi is to pump into a 3000psi gun.

Keep us posted!

BZ

[bubba zanetti]

few questions for those more knowledgeable than I. I disassembled my pump yesterday then cleaned and soaked it with some cerflon silicon spray it has set all night to dry. today I went to harbor freight to get the filter and was looking for plumbers grease well they didn't have any and I found super lube instead. will the super lube be ok to use with the silicon a sprayed on it yesterday, or will there be some kind of bad reaction?

 also the filter I have I just looked at it and not all beads are blue some most are purple and some look possibly pink. do I unscrew the big end to get them out?

 thank you.

Terry, good info. The HF filter worked for me but I did have one 'fail' early as the beads turned really quick and the pump had moisture in it. Good alternative and glad you posted!

BZ
I installed one of those HF filters on my pump and used it for several months, but I honestly don’t believe it did any good at all. Each time I opened the bleed valve I could feel moisture on my hand.  Also, the silica beads never changed color the entire time I used the filter.  I would have expected them to turn pink but they remained the same blue color. I got rid of the HF filter and replaced it with one I made based on the information I found in this post (http://www.gatewaytoairguns.org/GTA/index.php?topic=42922.0).  I used silica based kitty litter as the desiccant.  Now I don’t notice any moisture when I open the bleed screw.
As far as silicone plumber’s grease… I have seen it for sale in the plumbing section of Lowes/Home Depot.

[BigTinBoat]

Here is the filter

http://www.harborfreight.com/inline-desiccant-dryerfilter-68215.html


My benji pump is at my Dad's house so I can't check, but I think you will need a 1/4" to 1/8" NPT fitting, male on each end IIRC

like this



Then you put this QC fitting in the other end and can hook up your booster tank


I think my HF actually had both fitting I needed. I know they have the QC, not sure if I got the reducer there or maybe Lowe's.

[cwlongshot]

Thank you!!