Compression fitting-water pressure gauge
 

Okay, so I got some very nice used Gaffrig water pressure gauges from a member (thanks) and I got a water pressure connection kit from Gaffrig. The kit has a fitting different from the compression "donut" (ferrule) I am used to BUT I figured it would just tighten up under compression. It did not???
I put it together as seen in the picture and tightened it down real tight (but not enough to cause any damage...maybe not enough???) and the hose (that came with the kit) slipped right out of the connection.
Gaffrig is closed until Monday...any first hand experience/suggestions?
Thanks,
Tom
https://cimg7.ibsrv.net/gimg/www.off...0b9c8bee21.jpg

Okay, I just bit the bullet and cranked them down...installed, no leaks! :-)
I'm only seeing ~1-2 psi at idle (or just off idle) on the garden hose...is that "normal" for a big block with Hardin water pumps? When I bump it up off idle, I can see the pressure needle move in a positive direction but still not much than 2-3 psi.
Normal?

Yes, 1 to 2 is fine at idle on a hose. The hose cannot supply the same amount or water the pump can pump. In the water with new impeller and cold can get around 5, and after warmed up will be a bit less

Your probably not tightening it down far enough. If there are no witness marks on the hose then its not making enough contact. Ive seen ferrules like that but they usually go deep inside the body of the fitting and mate to a matching face. I had to look up the name and i believe they are Valco style fittings.
Im used to seeing the barrel/donut type ferrules for typical compression fittings. I just did a home humidifier and it had a compression fitting for the cold water supply....i cranked it down to what i thought was tight enough but it still seeped....kept tightening till it stopped and all is good :D

guess i took too long to look up the name lol :D

THANKS ALL...I love this forum!

I have always just used the standard round compression fittings from the plumbing section at the hardware store.
As long as the needle moves any amount at idle, you are fine.

You're welcome on the gauges :ernaehrung004:

They look good and thanks (to you and all) for the advise/support.

Finally pictures (with trim rings, etc...)
https://cimg6.ibsrv.net/gimg/www.off...d6170c1770.jpg

You need the little metal tube the goes in the plastic line. Plastic line will compress without the insert.

https://www.lowes.com/pd/B-K-1-4-in-...ing/1000505345
It is the little tube sticking out. Not needed with copper line but needed with poly.

Never used anything like this and never had any leaks. Regular brass compression fittings work fine on my water pressure gauges as well as my air actuated mufflers that use poly tubing.

Got everything to work by just cranking down on the connection. Thanks!

Need the inner tube piece for larger tubing, 1/8 tubing is not needed

Is there better tubing than the teflon I'm using. It seems to want to kink AND I have had two "holes" that sprayed water at speed???

I use 1/8" OD SAE J844 nylon air brake tubing. It's black in color. Got a 50' roll on Amazon 4 years ago.

The supplied fittings from the gauges worked fine with it.

Thanks...reviewing!

1/8" line can clog pretty easily and make water press readings very sluggish. Some have gone to 1/4". I've had to disconnect both ends and blow out the line at least once a season. I've found sand and rust particles in the line. I keep telling myself I'm going to "upgrade" but haven't done so yet. Something to consider..

I put mine on the intake and a idle I have 5pd at 3200rpm 10 pounds. I have the same gauge you have. I use the line and brass fitting that came with the gauge

I think I understand 10 psi at 3,200 rpms...but 5pd?
Today I had one water pressure gauge go dead after an idle zone. I stopped, put that drive in reverse (in case something got caught on the lower drive unit) for a second and then all was fine?

5 pounds at idle. I in stall this 20years and never had it fail. you can hook it to the cooler . it will read more.

I will look at hooking it to oil coolers as (even with new raw water impellers) I have never had a reading at idle...and then a couple of psi once the boat is moving a little (both engines 12+ psi max).