Water pump woes

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Water pump woes

Post  MrStationHouse on Sat 30 May 2015, 10:33 am

I am having difficulty with my water pump and with the steam test booked for Thursday would welcome any ideas, having spent all day fiddling with it.

I can see it is working if I take the delivery pipe off, when it is running I can hear the clack valve ball moving around if I do the old trick of holding a screw driver to the clack. This goes away if I turn the bypass on. However the level steadfastly refuses to go up ad just falls slightly. I am satisfied that the valve itself is open.

I have tried giving the ball less room and more room by adjusting the screw in the clack valve - as well that is as trying it with the required 6mm.

All to no avail. Also the gland always seems to leak with the valve set to delivery if I tighten the packing a little it stops briefly but soon starts again (I have repacked it today as well!)

The water always seems to leak from the bottom, I am beginning to wonder if the passage is oval (haven't checked this).

Finally if the pump is working satisfactorily how quickly does the level come up?

With best wishes
Simon

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Re: Water pump woes

Post  IanL on Sat 30 May 2015, 12:30 pm

Mine is very slow to show on the water gauge any increase in water level. However the feed pipe from pump to clack valve becomes cold indicating that water is going into the boiler. It was this method that my steam test examiner used .
I hope this helps and good luck with the test.
Ian

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Re: Water pump woes

Post  MrStationHouse on Sat 30 May 2015, 1:13 pm

Thanks Ian,

I am pleased your pump doesn't show much of an effect on the water gauge, did you speak to Steve at all about it? It should be more use than that, the idea is that it should be able to replace the injector.

If you are diverted to the clack does the water pump gland leak?

I did try the was the pipe cold, but it didn't seem to go cold, I think though it wasn't helped by the clack slightly passes steam and hence it was all pretty hot.

Thanks
Simon

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Re: Water pump woes

Post  Kevster on Sun 31 May 2015, 1:12 am

Have you checked the valve seats? Mine were porous ,full of holes didnt appear
round either,it would have never sealed ever.
not tried my pump under pressure as yet,keeping my fingers crossed it will work.
Kev

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Re: Water pump woes

Post  LiveSteam on Sun 31 May 2015, 6:29 am

The clack going cold on my 4" Agri is what I use to determine the pumps working, takes a while before it does go cold mind, also I find for it to show any real movement on the guage the engine needs to be running quite fast for sometime, remember the pump only puts in what I can imagine is an egg cup full in on each stroke.

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Re: Water pump woes

Post  lynnr on Sun 31 May 2015, 6:44 am

Hi

Best was of checking is as stated. Touch the feed pipe at the boiler and check for cooling and cold. Mine takes about 1 minute to go from very hot to cooling.

When Crystal is idling over with water pump on. She will take 15 to 20 minutes or more to get 1/3 glass gain on full cut back. When running 1/2 regulator on the road the water pump will gain on the glass only when cut right back.

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Re: Water pump woes

Post  MrStationHouse on Sun 31 May 2015, 8:25 am

Thanks all, useful thoughts.

I am fairly happy that the the seats are ok, the pump goes ok on the bypass and if I remove the pipe from the clack it pumps pretty well. I am interested in what you say Lynn that at full stroke it doesn't make any progress and it takes 15/20 mins to make a third of the glass. I was only trying for say 5 mins on full stroke.

How have you got on sealing the gland - does yours leak at all? If I tighten mine really tightly it will be dry for a little while especially on by pass but then leak under load. What ptfe rope are you using. I have some square section 3mm. Was wondering if I needed something a little thicker?

Best wishes
simon



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Re: Water pump woes

Post  IanL on Sun 31 May 2015, 8:31 am

I put three turns of the supplied PTFE rope to the piston, and it still weeps a little when pushing water into the boiler. Mine takes about the same time as Lynn mentions in her post to put water into the boiler, the injector is way more effective but only once above 100psi.

Ian

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Re: Water pump woes

Post  lynnr on Sun 31 May 2015, 8:46 am

3 rings of ptfe rope. Make sure the joins are out of alignment.
Polish the piston to quite a shine if possible and tighten up, until the packing gland starts bending in my case.

All of Crystals gaskets are made from Kellogg's Cornflake packet with a bit of oil smeared on both sides. No leaks even after joints have been taken apart a few times. She now had passed 400 hours in steam and quickly heading for 500.

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Re: Water pump woes

Post  MrStationHouse on Sun 31 May 2015, 11:57 am

Interesting - I clearly need to tightens pump gland more. Thanks for the advise Lynn

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Re: Water pump woes

Post  Tim Watson on Mon 01 Jun 2015, 10:08 am

Polishing the ram makes the pump much better for the packings.

Worth checking and re-doing the silver soldering on the pump pipes: STW did some Friday afternoon jobs in this area.
The pump is not as quick as the injector at chucking water into the boiler.  It is there to run in the background topping up as the engine is going along, especially down hip when gravity is helping the engine. Frederick's pump easily keeps up with demand.

The pump is a good 'get you out of jail' device when your pressure is low; and the fire; and the water - as happened to me on Saturday night after 2.5 hrs generating outside the beer tent and speaking to someone too long before going back to the peg!

Tim

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Soldering

Post  Steve Traill on Mon 01 Jun 2015, 12:12 pm

I had to resolder the pump feed pipes as they leaked air in & stopped the pump picking up. Visually they looked ok but with a finger over the end I could blow through them. With all the pipe ends if you can't see silver solder around the collar of the fitting assume it's a dry joint!

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Re: Water pump woes

Post  MrStationHouse on Mon 01 Jun 2015, 10:28 pm

Thanks all, I had another steam last night and made progress. When I spoke to Steve it became apparent that there was too much clearance on the clack valve - I had set the screw as per instructions but this gave about 3mm for the ball and it only needs 1mm.

After doing this the pipe easily went cool when the pump was engaged

I also solve the leaking gland issue in that the countersunk bolt securing the drive to the eccentric had come off and the eccentric was nearly off the axle. Thus the pump plunger was at an angle and not allowing the seal to work properly

Steam test Thursday

Best wishes
Simon

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