I'm still contemplating putting together my first custom loop so i've been doing some reading and came across this thread. I was just wondering if anyone here has tried this?
Anyone used a pressure gauge to leak test?
- Thread starter Goose
- Start date
What I do as a basic test is to put a bit of tube on a spare port on the res and either suck or blow into it via your MK 1 mouth. Sucking is probably easier to detect small leaks as after you've sucked you let the old tongue be sucked onto the end of the tube and leave it, ought then to be able to feel the pressure changing if there is a leak somewhere.
Soldato
- Joined
- 28 Dec 2017
- Posts
- 9,867
- Location
- Beds
There used to be a product known as Dr Drop. Same deal. Some people use them, I wouldn't say it's considered a requirement.
I've just built one but it's a bit fiddly to do, mainly because all of the parts I could find end up mixing tapered and parallel threads so it gets to become a nightmare matching things and sealing it. If you can source all of your components with parallel threads then you're golden and just a bit of PTFE tape on the threads will seal fine. I ended up using jointing compound on mine where I had to use tapered male and female parallel threads.
Apparently that Dr Drop actually leaks so it's next to worthless if you want to do a sustained pressure test.
Apparently that Dr Drop actually leaks so it's next to worthless if you want to do a sustained pressure test.
Only with the pump but you can use a bike pump you already have, I use one and it’s great to test for drops in pressure before filling.
If only just so you don’t have to drain and sort problems, pretty sure it was about £20 and worth it.
Mine doesn’t leak, sustained pressure is just fine when left to test at its limit and very helpful to see then find any leaks. As long as you remove the pump when leaving it should be good and sealed...
So far i've order one of these;
Mini Low Pressure Gauge
https://i.imgur.com/iLYO1Ey.png
And one of these;
1/4 Bsp Female 3 Way Tee Fitting
https://i.imgur.com/8j8Q5il.png
I'm hoping the following two items will complete setup;
British 25MM 1/8 BSPT BSP Schrader Tank Valve
https://i.imgur.com/VN0uaik.png
Bsp Male to Female Reducing Bush
https://i.imgur.com/eeObdXJ.png
This kind of stuff is very much out of my comfort zone so i'm fumbling around in the dark really.
I'm kinda thinking along this lines as well. Great if you don't find it's leaking - but what if you do? You could be on a hiding to nothing. First you need to find where the leak actually is, are you going to do a soapy bubble test on all the joints? It could be the seals on your waterblocks or pump so you would need to test them as well. Even then as you say, could still have been water tight in the first place.
Personally I think it's a good way of testing if there's anything obviously wrong where it doesn't hold pressure at all, but if you find that the pressure bleeds off over a length of time it then needs a judgement call if it will be good enough for water or not. I certainly wouldn't then be trying to find the source of the leak if a quick tighten of threads doesn't sort it.
I think you might be getting thread sizes and male/females mixed up there possibly.
Edit: or possible not - 1/8" M to 1/8" F to 1/4" M?
Edit (Again!) - I think your schrader valve is actually BSPT, rather than BSPP so you've got a possible leak source there.
Last edited:
Thanks for that. Fortunately i haven't actually ordered the schrader valve because i wasn't 100% sure if it was the right thing. I guess i'll have to keep looking for the right one (seems really hard to find?).
This is the description of the schrader valve from my previous post;
Personally I think you would be ok using PTFE tape on the threads to get it sealed, but you would likely have the same issue on the adaptor as it looks like it would be taper threaded on the otherside as well and personally I wouldn't want to have PTFE then in the tee in actual loop itself, just for getting bits of tape into the loop.
Edit: Thinking about it, I would probably see if I could get a BSPT to tube and then use a G thread tube fitting on the other end of the tube.
Fill it, put paper towels under all the fittings and on other risk areas (PSU/GPU) and use a jump adaptor on the PSU 24pin to fire up the pump.
Sure, you've got to partially fill the loop but it's simple and easy to do. You also don't risk causing damage putting pressure into components not designed to withstand such pressure.
You can make life easier putting a decent drain port in the loop in the event you need to to drain and fix the a leak. 2 minute job.
There's no need to be be nervous using the above method as your components are not electrified. That being said, coolant isn't conductive enough, if at all, in the event you get a little leakage. Just power down, clean up and let dry out.
Follow good practice and you'll be fine. For example - not overtightening fittings, inspecting for damage to o-rings, avoid pulling on fittings with tubing especially on rotary fittings as they can be susceptible to leaks.
Sure, you've got to partially fill the loop but it's simple and easy to do. You also don't risk causing damage putting pressure into components not designed to withstand such pressure.
You can make life easier putting a decent drain port in the loop in the event you need to to drain and fix the a leak. 2 minute job.
There's no need to be be nervous using the above method as your components are not electrified. That being said, coolant isn't conductive enough, if at all, in the event you get a little leakage. Just power down, clean up and let dry out.
Follow good practice and you'll be fine. For example - not overtightening fittings, inspecting for damage to o-rings, avoid pulling on fittings with tubing especially on rotary fittings as they can be susceptible to leaks.
Last edited:
You lost me there, i haven't even ordered any compression fittings yet and this is my first ever loop.
My intention has always been to test with air first and if all seems ok then test with water for 12-24 hours as normal. I'm being overly cautious but i've never done this before
@Goose you have bought exactly the same components as me!
I will tell you this right now, although the tapered male threads will fit in the parallel female threads, you only get actual contact between them at the very top which makes using plain PTFE tape a pain to use. I ended up using Fernox LSX jointing compound to fill the spaces between the threads and get a seal, but I had some lying around from sealing up 2 ports on a radiator where I couldn't use standard stop plugs.
Now that it's air tight it works fine, but it was a bit of a faff to get there.
Also note, as Smffy mentioned, make sure you detach your pump from the valve when you've pressurised because that will be a source of a leak. And don't go past 7psi when you pressurise (although you can take your contraption up to 1 bar when you test that in isolation).
I will tell you this right now, although the tapered male threads will fit in the parallel female threads, you only get actual contact between them at the very top which makes using plain PTFE tape a pain to use. I ended up using Fernox LSX jointing compound to fill the spaces between the threads and get a seal, but I had some lying around from sealing up 2 ports on a radiator where I couldn't use standard stop plugs.
Now that it's air tight it works fine, but it was a bit of a faff to get there.
Also note, as Smffy mentioned, make sure you detach your pump from the valve when you've pressurised because that will be a source of a leak. And don't go past 7psi when you pressurise (although you can take your contraption up to 1 bar when you test that in isolation).
Just thinking of how to connect the gauge/valve assembly to the actual loop. Personally I would use a 1/4" BSP hose tail/barb to what ever size of tube you're using and then your normal tube fitting on the thread (probably tie-ing into the fill port on your res).You lost me there, i haven't even ordered any compression fittings yet and this is my first ever loop.
The t-piece is 1/4 BSPP so that's exactly the same as our watercooling fittings. So just use any old barbs with hose and slap a jubilee clip on each end it to keep it tight, and then screw the other barb into a free port in the water loop.
Well i'm glad I was the right track then
Just to confirm, the little reducing bush thing should look like this ? - https://i.imgur.com/BzWZs7t.pngI have read about a lot of people struggling with PTFE tape but all the suggested alternatives cost so much i may as well buy a Dr Drop.