Model Boat Mayhem
The Shipyard ( Dry Dock ): Builds & Questions => Steam => Topic started by: BarryM on March 31, 2015, 09:46:00 am
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http://www.ebay.co.uk/itm/161127199918?_trksid=p2060353.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT
Does anybody have experience of using one of these and can advise on the performance? The pump mounting bracket looks a bit less than rigid.
Barry M
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Bonjour,
For reasons I do not understand when I go on eBay UK, I receive as response :
"Unfortunately, access to this particular item has been blocked due to legal restrictions in some countries. We are blocking your viewing in an effort to prevent restricted items from being displayed. Regrettably, in some cases, we may prevent users from accessing items that are not within the scope of said restrictions because of limitations of existing technology. Please accept our apologies for any inconvenience this may cause, and we hope you may find other items of interest on eBay."... No comment...
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Able to access here in Uk without a problem.
LB
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Bonjour,
For reasons I do not understand when I go on eBay UK, I receive as response :
"Unfortunately, access to this particular item has been blocked due to legal restrictions in some countries. We are blocking your viewing in an effort to prevent restricted items from being displayed. Regrettably, in some cases, we may prevent users from accessing items that are not within the scope of said restrictions because of limitations of existing technology. Please accept our apologies for any inconvenience this may cause, and we hope you may find other items of interest on eBay."... No comment...
No problem here in the UK. I know nothing about Steam stuff, but that looks like a tiny motor on the pump??
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Hi Barry I purchased one of these pumps for my steam plant and had a few queries I posted on here .I've not completed the installation yet but from the replies I got an Australian guy seem to use them OK as is I think.
Read the posting coolbumble Feb 18th there are a few pictures to. I'm sure your get some helpful hints from them
Regards
Ian :-))
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Ian,
Thanks for that and the heads up to your posting. My concern was that the mounting plate which attaches motor to pump might flex when the pump is under load but I assume that it is not a problem? Also the output as given on the Ebay advert is 270ml/hour which seems very low. I have asked them to clarify the figure; possibly 270ml/min?
Regards,
Barry M
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Bonjour,
For reasons I do not understand when I go on eBay UK, I receive as response :
"Unfortunately, access to this particular item has been blocked due to legal restrictions in some countries. We are blocking your viewing in an effort to prevent restricted items from being displayed. Regrettably, in some cases, we may prevent users from accessing items that are not within the scope of said restrictions because of limitations of existing technology. Please accept our apologies for any inconvenience this may cause, and we hope you may find other items of interest on eBay."... No comment...
This could be because the item has not received CE approval, and maybe also because of the nature of the item (steam has more potential for danger). Perhaps the French authorities are more rigorous with their safety laws.
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I have two of the Chinese piston pumps....one paddle shaft driven [planned to 140 RPM max], the second as an electric driven auxiliary [alternate 12 Vdc @ 70 RPM]
The bore = 6 mm, the stroke = 5 mm....so the theoretical displaced volume is ~~141 cubic mm
I too have not commissioned either pump......just waiting on manufacturing an onboard water tank.....say 750 ml?
The pump bracket [laser profiled] is substantial & I have no concern about flexing or distortion ......the only issue I have with the paddle shaft driven pump is that it with my mounting, it is vertical shaft down, so the lubrication oil from the eccentric can drip down & enter the open gland annular area as the pump is displacement by design and the only seal is the 4 x 1 section o-ring on the piston rod/shaft
The basis for the alternate 12Vdc geared motor was the original as supplied 140 RPM assembly sounded like a VW engine <*< & the current draw was excessive ...the manufacturer offered to replace it but the return APP cost to China was more expensive than the original complete purchase..............
The only other area of concern were the nylon washers on either side of the banjo bolts......these seemed to displace & never tighten....so I replaced these with RED fibre washers
The first image is the paddle shaft driven pump, the second is the 70 RPM auxiliary electric pump.....
PS...have also installed a larger lube oil reservoir to the eccentric body on both pumps........they also near mirror the sizing of the lube oil reservoirs for each of the engine shaft journals....... Derek
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Hi,, i Got 2 of this pump never got a problem,,
https://m.youtube.com/watch?v=qZef1-riGLw (https://m.youtube.com/watch?v=qZef1-riGLw)
https://m.youtube.com/watch?v=TB5hisIRWTc
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Thanks for all the reassuring answers. I'm still waiting on an answer from the sellers re. capacity but if I get one I'll post it on here.
Regards,
Barry M
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What engine and boiler is it for,,, it is a strong. littel pump
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3.5" Maccsteam and 'Bogstandard' twin.
Barry M
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hi.. ok....... it supply a lot more water to my boiler than engine can use tvr1a .. i have to have a serve to open/close the water to the boiler
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Hi Barry
I just did a test on mine NOT connected to the boiler but running continuously for 5 minutes with a 12 volt battery it pumped 160ml
Hope that helps.
regards
Ian :-))
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Thanks Ian - that's helpful.
Barry M
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Hi again
One thing I should of mentioned I did note that oil should be used sparingly and only via the eccentric oiler as any oil on the plunger it stopped pumping although it still rotated It needed a thorough clean and degrease of the whole unit before it worked again ! I don't know if anyone else has had the same experience.
Regards
Ian
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hi yes i have try that to,, so only via the eccentric oiler,,
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Guys......the design of these single action piston pumps is via the pressure energised O-ring on the piston rod...[or in the gland in other builds]...
If you are pumping to an atmospheric tank, the O-ring does not energise and simply relies on friction or stiction to transfer the fluid...[the friction is also created by the force to transfer the single slug of water and any such pipe/tube friction losses which in our cases are negligible ]
The difference between pumping water at zero pressure and pumping water with a mix of oil at zero pressure is lubricity related ie., water having a lower lubricity
So the experience offered by coolbumble below is not a fault of the pump
The O-ring must be deformed...ie., pressure energised to perform the drip tight transfer of fluid...... such O-rings will happily perform against far greater boiler pressures that we contemplate
O-rings are used as dynamic piston seals in millions of industrial applications where oil hydraulic fluid is the medium ...so have no fear of the humble O-ring :-))
The as supplied 0-rings in my two pumps are green or a VITON elastomer which has a low tear and abrasion resistance and should ideally be replaced with standard NBR or nitrile O-rings which are totally compatible with raw water........
Without getting too far off track, an O-ring any application requires clean fluid to maintain both it self & the pump bore
A single grain of sand [silica] can be far harder than the bronze pump bore or stainless piston.....that grain of sand embedded around the O-ring will score the pump bore and render it as useless as the scored bore will shred the O-ring and cause water bypass......
Some members [Jerry C] is/are fortunate to steam on pristinely clean water.........others who are not should consider a form of water pump suction filtration ....or consider on-board water makeup tanks......Derek