Pump repair?

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fausto99
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Joined: 19 Sep 2011, 10:06am
Location: NW Kent

Pump repair?

Post by fausto99 »

I have a Park floor pump PFP-6 which now won't go above 80psi. I can hear it hissing but can't find the leak/crack?
I've looked at all the O rings and can't see any wear.

Anybody have any tips for tracking down the problem?
Jdsk
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Joined: 5 Mar 2019, 5:42pm

Re: Pump repair?

Post by Jdsk »

Have you found "PFP-6 and PFP-3 Floor Pump Service":
http://www.sjscycles.com/Instructions/P ... ctions.pdf

Jonathan
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fausto99
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Location: NW Kent

Re: Pump repair?

Post by fausto99 »

Jdsk wrote: 14 Oct 2021, 9:59am Have you found "PFP-6 and PFP-3 Floor Pump Service":
http://www.sjscycles.com/Instructions/P ... ctions.pdf

Jonathan
Yes I had downloaded that although I didn't actually consult it because the dis- and re-assembly is pretty straightforward. I'm thinking soapy water is the way to go.
drossall
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Location: North Hertfordshire

Re: Pump repair?

Post by drossall »

Most common is leaking at the head, where it seals onto the valve, of course. But you've eliminated that?
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fausto99
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Location: NW Kent

Re: Pump repair?

Post by fausto99 »

Definitely not the head. I can hear hissing near the pump not near the wheel. I just can’t narrow it down yet.
jb
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Re: Pump repair?

Post by jb »

Put the pump in a bucket of water and pump up a tyre.
Cheers
J Bro
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fausto99
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Location: NW Kent

Re: Pump repair?

Post by fausto99 »

Hmm. Don't think I have a bucket big enough.

Can anyone give me any pointers as to how to measure O-rings?
Can anyone recommend a supplier who will do small quantities?
Park Tool have disowned it as being too old to supply spares.
ElCani
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Joined: 5 Mar 2015, 11:24am

Re: Pump repair?

Post by ElCani »

I just ditched one of the these with the same problem. I tried servicing it but then ended up buggering up the plastic threads trying to get it tightened enough to stop the leaks. Annoying, but I've just bought an SKS Rennkompressor which has metal fittings and basically every part can be replaced. The dial is very hard to read though...
jb
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Re: Pump repair?

Post by jb »

fausto99 wrote: 14 Oct 2021, 8:26pm Hmm. Don't think I have a bucket big enough.

Can anyone give me any pointers as to how to measure O-rings?
Can anyone recommend a supplier who will do small quantities?
Park Tool have disowned it as being too old to supply spares.
Inner diameter & cross section diameter. best to measure the diameter of the groove it fits in if you can. There are about a billion different o rings about, sometimes your best off buying a selection box but it needs to have the right cross sections in and to be either metric or imperial. I'd assume metric but Park Tool are American...
Cheers
J Bro
Jdsk
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Re: Pump repair?

Post by Jdsk »

fausto99 wrote: 14 Oct 2021, 8:26pmCan anyone give me any pointers as to how to measure O-rings?
Can anyone recommend a supplier who will do small quantities?
"How to Measure O-Rings":
https://www.manuf-rubber.com/resources/ ... ing-chart/

You can buy boxes of mixed sizes from Aldi, Lidl, Screwfix, eBay etc. Edited: Crossed with jb's above.

But if you only need a few I suggest asking here and hoping that someone is helpful.

Jonathan
Stradageek
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Joined: 17 Jan 2011, 1:07pm

Re: Pump repair?

Post by Stradageek »

I struggled to find the correct size in any shops so bought these: https://www.ebay.co.uk/itm/141455807139

I measured carefully using a micrometer then assumed it was the closest standard size.

Worn O-rings have an obvious 'flat' so beware when measuring

Problem solved :D
Pebble
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Joined: 7 Jun 2020, 11:59pm

Re: Pump repair?

Post by Pebble »

fausto99 wrote: 14 Oct 2021, 8:26pm Hmm. Don't think I have a bucket big enough.
fill the bath up and lie it on its side when you can hear it hissing.
thirdcrank
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Re: Pump repair?

Post by thirdcrank »

I don't think you need to submerge it completely if that's a problem. Make a strong solution of washing-up liquid (in water) and coat it with that. The leak should be visible with a load of bubbles.

I'm not familiar with this pump but if the problem only occurs above a certain pressure, perhaps it's an internal valve.
NickJP
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Location: Canberra, OZ

Re: Pump repair?

Post by NickJP »

fausto99 wrote: 14 Oct 2021, 8:26pm Hmm. Don't think I have a bucket big enough.

Can anyone give me any pointers as to how to measure O-rings?
Can anyone recommend a supplier who will do small quantities?
Park Tool have disowned it as being too old to supply spares.
When I needed to replace the O-ring in my Serfas track pump, I just went to a local bearing supply shop with the damaged O-ring from the pump and bought a couple of replacements in the closest matching size they had. The replacement has lasted considerably longer than the original that came with the pump.
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Sweep
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Re: Pump repair?

Post by Sweep »

Have you greased the O rings?
I had a malfunctioning track pump once - greased the rings with some appropriate (ie O-ring friendly) grease and all was sorted.

There was nothing seriously wrong with the actual O rings.
Sweep
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