How tight for water sediment screen and filter housings?

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aenlic

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I've long had to err on the side of caution when making things 'as tight as possible...' as in, they break.

I just 'finished' (but not done yet) replacement of the freshwater pump and filter (element and housing). Once I had the wiring done, I turned it on and... had impressive leaks at both the pre-pump screen filter and the post-pump micron filter.

The pump is a Shurflo Aquaking II, rated at 3 gpm, and though the filter element 'recommends' 2gpm I didn't think that would be a problem... is it?

I can tighten both housings more, but didn't think anything beyond 'firm' was required... is it?

I've done a lot of house plumbing, but this is my first boat plumbing. I'm spending another night without running water, will face this fresh tomorrow.

Any input appreciated, as always...

Bob
 
Did you check for the O rings presence?
If the screen and the filter housings are plastic then you may need to use a SILICONE GREASE to lightly coat the threads and the O rings.
I've found that without the grease the threads tend to stick making you think all is tight when it is not. ALso without the silicone grease the housings can be the dickens to undo when you need to.
 
Ditto on the silicone grease. Helps seal o-rings, lubes sticky single lever faucets and works anywhere rubber gaskets and seals rub.
 
+1 on silicon grease. I would add that if you have screw on with o ring do not over right them or you may squeeze the oring. Same with compression fitting, too tight and you may damage them. Where was the leak? At the filter housing or the filter fittings?

L
 
Every household filter I've ever bought was pre-lubricated, and the o-ring on the filter felt lubricated. The sediment screen was pre-assembled, but loosened while I was installing the pump, so I retightened it.
I'll get back to this later today, hope to get it resolved then.
Thanks-
aenlic
 
Could be wrong, but dont remember any o rings or washers in those Shurflo fittings.

This is from the manual...note the comment about fittings.

"❚ Installation of a 50 mesh strainer such as SHURflo 255 series is recom- mended to prevent foreign debris from entering the pump. SHURflo hex/swiv- el barb fttings provide easy removal if maintenance or access is required. The fttings are designed with a "taper-seal", creating a water tight connection when hand-tightened. Always secure barb tubing connections with properly sized stainless steel clamps to prevent leaks. Never use Tefon tape or sealing com- pounds on threads. Sealer may enter the pump causing a failure. Failure due to foreign debris is not covered under warranty."
 
Vaseline for lubricating the O-rings.
I worked at a place that machined filter housings and that was the factory and preferred lubrication. Just enough to make the o ring feel slippery.
If you don't use some kind of lubrication the o ring can bunch up and feel tight before it is sealed.
 
Where exactly are the leaks? From the folter housings or the connections?

This is from the Shurflo strainer manual....nicecall Jay on the petroleum jelly.....

"1. Close the valve or drain water source (tank) as necessary. OPEN a faucet to relieve pressure within the line, then switch OFF power to the pump. This procedure will purge most of the water in the inlet (suction) water line, however use pan or bucket to collect any remaining water.
NOTE: Other electrical components in the vicinity should be switched OFF to prevent electrical shock.
2. Support the housing while turning the cover "ears" counterclockwise, until the tabs align in the notches. Carefully wiggle the cover out of the housing to overcome the seal of the O-ring.
3. The strainer screen can be removed to aid in cleaning.
4. Reinstall the screen in the housing. Apply petroleum jelly to the O-ring to assure a positive seal.
5. Align the locking tabs of the cover in the notches of the housing. Push together then turn clockwise until in the "locked" position.
6. Open the water source valve and switch ON any power turned off previously. Open the faucet and allow the pump to operate. Inspect strainer and connections for leaks."
 
Thanks both... I'll pick up some petroleum jelly this morning.

psneeld, you may have helped me dodge a major bullet regarding teflon tape. It'ssuch a deep-seated practice that it never occurred to me that it could be inappropriate in this situation.

On the input side, I used it on the input threads of the screen housing and on he nylon npt-to-barb fitting. I hope nothing has already gotten into the pump, but I'll back out those fittings and remove the teflon tape.

I'm surprised that the nylon fittings can be watertight without the tape... can you confirm that they are? Or do I need to get a Shurflo npt-to-barb fitting?

Thanks-

aenlic
 
None of my screw together fittings are anything but plastic on plastic like hydraulic fittings steel or brass on same. No washers or O rings.
 
Vaseline for lubricating the O-rings.
I worked at a place that machined filter housings and that was the factory and preferred lubrication. Just enough to make the o ring feel slippery.
If you don't use some kind of lubrication the o ring can bunch up and feel tight before it is sealed.

NO PETROLEUM PRODUCTS e.g. Vaseline should ever be used on plumbing rubber parts. It will attack the neoprene and soften it, make it swell, or leak. Turns rubber parts to goo. Parts for engines and hydraulics are made to use with oils, different material, usually nitrile.

From 30 yrs running a service business, I can attest that plumbing and vaseline don't play well. Use silicone grease or dielectric grease. The filter housings will do much better with silicone grease, you may have trouble with the plastic galling if you don't lube it and make it too tight, may even break it getting it apart.

For the fittings in the plastic housings, use 2-3 wraps of teflon tape wrapped the direction of assembly so it doesn't unravel, 1st 2 threads bare. I always "double-doped"- teflon wrap plus a coating of good quality dope- Rectorseal #5 or "Leak Lock". Don't make fittings in plastic up any tighter than needed to keep from leaking. If making up a male fitting in a plastic female fitting, put a stainless hose clamp on the female fitting if possible to support it so it doesn't split, it'll also keep it from leaking with temp. changes, and you can usually stem a leak just by snugging the clamp.
 
My only concern was with omitting the teflon tape. I spoke with Shurflo tech support and my concerns are eased. The warning is only for the Shurflo swivel twist fittings and 'surplus' tape on nylon fittings.
Looking forward to getting back to this later today, thanks again.

aenlic
 
Steve, I just re-read your note and caught the bolded warning against Vaseline... thanks.

A jar of silicon grease is on its way to me; I have plenty of other projects to take up the time until it arrives. Running water (especially HOT water) will be truly appreciated by the time I have it. ;-)

Thanks-

Bob

NO PETROLEUM PRODUCTS e.g. Vaseline should ever be used on plumbing rubber parts. It will attack the neoprene and soften it, make it swell, or leak. Turns rubber parts to goo. Parts for engines and hydraulics are made to use with oils, different material, usually nitrile.

From 30 yrs running a service business, I can attest that plumbing and vaseline don't play well. Use silicone grease or dielectric grease. The filter housings will do much better with silicone grease, you may have trouble with the plastic galling if you don't lube it and make it too tight, may even break it getting it apart.

For the fittings in the plastic housings, use 2-3 wraps of teflon tape wrapped the direction of assembly so it doesn't unravel, 1st 2 threads bare. I always "double-doped"- teflon wrap plus a coating of good quality dope- Rectorseal #5 or "Leak Lock". Don't make fittings in plastic up any tighter than needed to keep from leaking. If making up a male fitting in a plastic female fitting, put a stainless hose clamp on the female fitting if possible to support it so it doesn't split, it'll also keep it from leaking with temp. changes, and you can usually stem a leak just by snugging the clamp.
 
Steve, I just re-read your note and caught the bolded warning against Vaseline... thanks.

A jar of silicon grease is on its way to me; I have plenty of other projects to take up the time until it arrives. Running water (especially HOT water) will be truly appreciated by the time I have it. ;-)

Thanks-

Bob

Sorry, the Vaseline was from the factory that built the housings. They never leaked.
 
Sorry, the Vaseline was from the factory that built the housings. They never leaked.

Funny how Shurflo recommended it right in their manual.

I am sure some applications it may be a no no even though the manufacturer used it, but Shurflo has been around awhile and sold a lot of stuff between boats, RVs, agricultural applications, etc...
 
Most excellent, a variety of answers... which I'm thinking are all correct.

My guess is that the Great Vaseline Taboo applied to the materials being used at the time. Perhaps some gasket/O-ring material still in use will react badly to petroleum jelly, don't know... so I'll go ahead and use the silicon grease to be on the safe side.

Again, very grateful for this forum. :-D

aenlic
 
I just installed an o ring 2 days ago that specified Vaseline as lubricant prior to installation.
 
Vaseline for lubricating the O-rings.
I worked at a place that machined filter housings and that was the factory and preferred lubrication. Just enough to make the o ring feel slippery.
If you don't use some kind of lubrication the o ring can bunch up and feel tight before it is sealed.

Did we just time warp to the seventies?
 
Did we just time warp to the seventies?
Well, personally I feel like I just time-warped to the 21st century. ?
Having running water, especially running HOT water, now feels like a luxury rather than an expectation.

aenlic
 
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