Anybody here do this?
Tips?

 

all a leak down test is when you do a compression test you time how long it takes to come off the psi readin on the gauge.

 

I'm sorry sir, but you are incorrect.

A leak down test, is putting compressed air in the cylinder, whilest piston is at TDC. More than 10% pressure loss indicates bad valves, gaskets, rings or a cracked head. No piston movement required to measure psi.

A compression test, measures the amount of pressure created when the piston moves to TDC. You turn the motor over, creating piston movement to measure psi.

I had asked about making a DIY leak down tester, not what the test is.
Now, if I am misunderstanding this technique, please speak up.

 

I have read where I need to use an air damper in the tester. I was wondering if it could be replaced with a ball valve that can be closed, once cylinder is charged?

I'd like to put this togather today but some feedback is desireable. Is that not what the forum is for?

 

there isnt any way to watch the air pressure drop while you have a compressor hooked to it/ you need a compression gauge to do this. ive done this a thousand times. im not some kids sittn back lookin on google just to argue. you disconect the coil and hook your gauge to the cylender you want to check. you turn the motor over 5 revolutions and stop right when you feel the gauge kick in your hand. that way you know both valves are closed and watch how fast the psi drops. me and a freind hooked a air compressor to one of his cylenders on his truck and could hear air comin fron the intake with it a tdc on the one we were checkin. this is after we done a psi check i=on it and found out it was leakin. that told us there was somthin wrong with the intake vavle. we swaped the head and she runs like a champ. hope this helps you.
oh and p.s befor you come to this site tellin ppl there wrong remember your the one on here askin the ?s.

 

+1 on this frydaddy

 

ok i stand corrected there is a leak down tester but you can do the same thing with the hose you get with the compression tester. pull your valve cover and make sure both rocker arms are up on the piston your checkn. take the plug out and screw in the hose that comes with the compression tester. hook your air to this hose and listen at your t.b if you dont hear any air the pull your dip stick and listen there. and also go to the tail pipe and listen for air. if its comin out the t.b then its a intake valve leakin. if its comin out the tail pipe then its a exhaust valve. if you can hear it comin out the oil dip stick then your compression rings on that piston is bad. and the reason i never seen a leak down tester i guess is cuz i have enough common sense to self diagnose with out blown money on things i dont need

 

Hmm! I thought I was polite about. You yourself just stated I was not wrong.
Again, I was hoping for some feedback, not a dressing down for being in the ball park. I'm glad your a trained mechanic. I am not. If I was trained, I would not be asking questions here, now would I. All you have stated so far is that I'm wrong and repeated what I've said.
What is the purpose of this forum if not to get educated. I have to do my own work because every professional I've come across has done poor work or tried to take advantage of me.

Now, I had asked if by using a ball valve, that could be closed after cylinder is charged, will that be OK to cut out the compressor to see the
pressure loss?

A compression tester gauge holds its highest reading till reset, yes. So how is that going to show pressure loss? How is doing a compression test the same as a leak down test? One use use the cylinders mechanical compression, one adds air pressure to a closed cylinder.
A DIY Leak Down tester is a couple of bucks. A bought one is quite a bit more.

When I am wrong, I accept it and learn. I also apologize to those I have wronged. Not looking for one either.
I'm not a pro mech, but I work and build with wood, steel, fabric, water, air, and electricity. All the assundry tools that go with. Various types of machinery and many types of semi-complex systems. I am quite secure in my abilities.

 

well bud i pretty much told you how to use the hose off a compression tester. wish you the best of luck.