I have a cylinder leak down test kit. Instruction say to connect the fitting to the spark plug hole, then connect the gauge setup, then make sure the regulator **** is all the way off.
Then connect the air compressor.
Then to slowly open the regulator knock until the % gauge reads 0%.

It then says you can read the leak down % ?? WTF it will be 0% then..

If you just put it at 0% it will stay there...crank the regulator open and the needle goes below 0%..close it and it goes back up near 100%

It doesn't say to do anything with the PSI gauge.

How do you use this thing? I assume they are all the same, has 2 gauges, a % leak and a psi gauge with the regulator.

 

Normally the regulator is going to provide 80-100 psi pressure. When you have that pressure regulated (your particular gauge might read it as "0") and you are letting that pressure flow into your cylinder that is at TDC, the other guage (that is between the regulator and the cylinder) will read what pressure is acutally holding. Whatever the difference between what is being applied by the regulator and what is holding in the cylinder is the amount of leakage.

 

I've read a ton of articles on how to do this..and there is something I'm just not getting or my gauge is broke, its brand new!
This is the setup I have


Instructions say to open the regulator until this gauge reads 0%


When I do that, the other gauge, the PSI gauge reads about 6 PSI..If I open the regultor more for more PSI, the neddle on the other gauge just pegs backwards past 0%..if I lower the PSI any lower than 6psi, the needle then just goes to 100%....

What Am I missing, if I set the regulator to say 80psi..the leak gauge will just be pegged backwards past 0% ???

 

Here is an article using the guage you have... http://www.carcraft.com/techarticles.../photo_02.html

You set pressure with the cylinder hose disconnected. Once set to zero, you connect it to the hose and the cylinder.

 

Ah..thats the part that was missing from my instructions..it said to connect it all up then open the regualtor...makes sense now.
Thanks!

 

Well I gues my guage is whacked. The only way its sets to zero with the cyclinder hose disconnected as with about 2-3 psi of pressure reading on the other gauge. If I open it up to 80psi, the leak gauge is buried wrapping around past zero....well below 0%.

I'll take it back to exchange tomorrow I guess.

 

you broke it trying to adjust it with pressure on it...dummy

 

First time trying was with it hooked to the cylinder, the regulator was always completely off to start with, and immediately it went to 0% at 10 psi or so. If it was not hooked to the cylinder it would go to 0% at 2-3 psi which was after trying it hooked to the cylinder per the instructions.
And it never had more than 80psi to it with regulator off, book says it can handle up to 100psi input which it never had.
Wasn't that expensive of a device compared to other brands so I'm sure the defect ratre is quit high as with other chinese products

 

Maybe I am a dummy here. Got a new gauge, it behaves the same, and at this point I have not cranked it past 10psi.
With the hose disconnected from the cylinder hose, it only take 2-3psi to pegged the gauge to 0%...anymore it will wind it past 0.
With it connected to the cylinder, all it takes is 10psi to get the gauge to 0%.

Opposite of what is said above, the instructions clearly state:
-Get cylinder to TDC
-Turn regulator **** fully counterclockwise.
-Connect to compressed air source.
-screw in adapter hose into spark plug hole of cylinder
-Connect the male end of adapter hose to female extension hose from gauges.
-TURN REGULATOR **** CLOCKWISE until Leakage Guage reads "0%"...which is 10 PSI at this point.
-You can now read the amount of Leakage on the leakage guage as a percent lost....... How is that because I just set it to 0% in the previous step and its not going to move after doing that?????


The only way I see to use this is read the amount of PSI it takes to make the leakage gauge read 0% and either divide that by 100psi or divide by 180psi which is what each cylinder measures during a compression test and that would be the % lost....which is no where near what any instruction says to do and makes the % markings on the gauge useless.