Any Plumbers in the house?

[Wayout]

 Buzzing (vibrating) cold water pipe.  A few months ago the hot water tap on the bathtub started dripping.  No big deal, I've changed the washers before.  Everything went smooth or so it seemed. When I finished the cold water pipe started buzzing.  Only when the bathtub cold water was turned on and then only when opened about 1/3 of the way.  No problem I though, I'll turn off the water where it comes into the house, open all the faucets and drain the system.  That seemed to work for a few days then the buzzing returned.  I've repeated this procedure several times and it does 'fix' the problem for several hours to several days but the buzzing returns.  Is there something I'm missing?  

I've lived in this house for 35+ years and never had this problem before.

[Golfer]

City water or a well?

[VonMessa]

Constant or when you shut off the water?

[Golfer]

I'd look at the pressure in the system. If the pressure reduction valve (if city water) coming in from outside and/or pressure regulator in the house. You can easily and cheaply measure the water pressure in your house and go from there.

If you're not comfortable remember the most important words of home ownership. Pay The Man.

[Wayout]

City water or a well?

City water.

[Wayout]

Constant or when you shut off the water?

Only does it when the water is turned on about 1/3rd of the way and only from the cold water faucet in the bathtub.  Any more than 1/3 open or any less than 1/3 open there is no problem.

[Wayout]

If you're not comfortable remember the most important words of home ownership. Pay The Man.

I bet Plumbers love the weekend handyman. 

[VonMessa]

Sounds like water hammer to me.  I am not a plumber, but I did play on on TV once.

[Babalonian]

When you replaced the seats on the hot water valve, did you depressurise your entire system?  For how long was it depressurised?  Would you in any way, intentionaly or accidently hit/smacked/braced against/on the cold water valve or pipes imediatley around the tub's cold water valve?  35+ years.... first owner?  Original plumbing?  Are the pipes steel (and @ 35yo    I found your problem most likely), or what are they?


You're sure it's only the cold water faucet in our house with this problem though?  Since it's a good and cheap thing to do anyways, will probabley get some good answers if any are to be had, and I just know you love to play plumber - I recommend you do the valve seat on the cold water faucet/valve in the tub too.  Pay attention while dissasmbling for any corrosion or debri clearly visible.  BEFORE reasembling the valve, but after you've removed the old seats, we're gonna want to flush out that cold water pipe.  Try to do two... well three things when you briefly flush it out by turnign the water briefly on then back off.  Avoid water hammering your system by turning the water on too fast at the main valve, while also being brief and fast and gettign a good flush through.  Second, avoid making a mess or hurting anything/one which ties into the third thing - try to strain/catch the flush in a rag or sponge, this will minimise spraying water 20-ft across your bathroom while also revealing/catching hopefuly some evidience of what is hopefuly debri/crud.  And do be careful - at best it's an old chunk of lead solder from your old pipes and the aprentice plumber that helped install them - and it will come out of your pipes in the flush like a shot (I got a funy story about that, I was on a ridealong with the fire dept to shutoff a sheared hydrant one day, two guys holding up a tarp to shield the shower from the one cranking the street valve, and one of the tarp guys suddenly falls to the ground like he took a ~10lb sledge thrown 50-ft up to the top of his head - he did, chunk of dislodged over-generously-aplied lead solder).


I'm not a plumber, but I design and engineer commercial irrigation systems to pay the bills.

[Babalonian]

Sounds like water hammer to me.  I am not a plumber, but I did play on on TV once.

Only as a possible cause I think, if he turned the water back on gingerly and lovingly, he wouldn't of hammered his pipes hard enough to dislodge some notable and large enough chunks of corrosion/debris/crud from within his 35yo steel pipes, which will then travel and cause constriction/blockage/havok behind the valve or somewhere else in the system - thus leading to his current problem of I suspect water turbulence - aka vibration.  He didn't do this because then the first thing after hammering his system from restoring the water would be to check his craftsmanship, opening those valves in the tub he was jsut working in and essentialy funneling any recently dislodged debris to that demand source....    (yeah, I've maybe done this myself a few times ). 

When he now shuts off and depressurises his system, and then vents or drains it further, the debris is falling back, but when restored it gets shoved right back up against whatever is lodging it eventualy.  (I advise you stop doing that if you don't have to btw, it's causing further corrosion if you're intorducing air even briefly and definetley some more dislodging of deposits/crud in your pipes with each further hammer and repressurisation administered).

Pressure problems would only happen if you adjusted (maybe inadvertently when trying to shutoff the water the first time) the pressure regulator or if it's taken a dump.  Not unheard of but unlikely.  If the PR is that gone you would notice the higher pressures throughout your house, not to mention something else in the 35+ yo system would also start to go from too much pressure rather quickly.

[FireDrgn]

Since it only happens when cold is run. I would say its within the cold side stem. I have seen a loose stem vibrate or flutter when partially open. Thats what I would check first .

I will send a pm with my phone number ..  text me or call I can walk you thru just about anything..
 

[Copprhed]

Common problem, everyone's overthinking. pull your stems, make sure the washers are seated correctly and make sure the screws holding the washers are tight. Sounds like washer vibration to me.

[morfiend]

  Wayout,


  You never said if the pipes were copper or the old steel/iron type. The noise is a result of vibration in the pipe from the water flow. You could have moved the manifold just slightly enough when you fixed it to cause this to manifest.

   Something as simple as some pipe insulation place in the proper place can pretty much stop the noise,or even a simple tap on the pipe with the handle of a hammer.

  since the system is so old you likely dont have any bumpers in the lines.usually they are installed close to the laundry facilities as they are subject to sudden starts and stops of flow and this can cause the issue Von mentioned.

   I would replace the seat and washer,easily done, and see if that doesnt fix the problem,slight amount of debry,washer wear can also cause that hum you hear.


   I'm almost certain that the repair moved the manifold just enough to make the noise!  If replacing the seat and washer doesnt solve the problem,you may need to access the manifold in the wall and resecure it or wedge it so it can move anymore.


   YMMV.


    

[Babalonian]

Since it only happens when cold is run. I would say its within the cold side stem. I have seen a loose stem vibrate or flutter when partially open. Thats what I would check first .

Yes but (in a case of "not there before, but there now") usually from accidental damage that he would/should know about being done to that valve's stem - why Im asking if he can recall hitting/knocking/prying on it during the hot water repair (or, hopefuly not, his or someone elses knee or head during a fall, ouch).

Possible the seal around the stem on the cold valve is bad now or was going bad and the hot water repair something happened to of cr@ed it out.  If this is true, he likely should see water comming out of the valve at the stem now.

[Babalonian]

Common problem, everyone's overthinking. pull your stems, make sure the washers are seated correctly and make sure the screws holding the washers are tight. Sounds like washer vibration to me.

What I thought, but it's the valve he hasn't touched and didn't have a problem with before, as I understood it.  Hot water, the one he reseated, is fine.