Help With Leak Down Test

[YoshiMoshi3]

Considering doing a leak down test on my 2014 Acura TSX that's burning oil. Am I able to do this test with a tire inflator or even a hand pump. I have done this before in school, but never at home. Can I just use a tire inflator or hand pump? I understand the basic operating principles. But the cylinder in top dead center so intake and exhaust valves are closed. Put in a new pressure into the leak down test tool. Set the pressure into the cylinder. Leave it for so many minutes and see if it hold the pressure.

I'm thinking that say the target is 135 psi. Can't I just use my Milwaukee M18 tire inflator so that it goes to 135 psi, then open the valve so that the pressure goes into the combustion chamber as well, resulting in the pressure going down, then re-run the tire inflator so it's 135 psi and see if it holds it.

Also when I have done this before I was able to find procedures in like ShopKey or AllData. But I'm not able to find a procedure for a leak down test in this car in ShopKey. I can't like for example find what pressure I should use. I don't want to use to much.

Thanks for all help!

 

[NutsBoltsElectrons]

A leak down test doesn't test the oil control rings that are gummed up with carbon. Might be worth trying to soak them in a chemical treatment before the re-ring job.

 

[zimman]

If it's burning oil you know what's up. It's time for a change. It's probably down on power also.

A leak down test doesn't test the oil control rings that are gummed up with carbon. Might be worth trying to soak them in a chemical treatment before the re-ring job.

I see what you did there. LOL
Zim

 

[rust in the eye]

The procedure isn't as you describe. A leak down gauge set gives a comparison of pressures, input pressure and that in the cylinder, the diffrence being percentage of leakage. You may have good leak down results and still consume oil via valve guides/seals, oil ingested through leaking gaskets, etc.
To answer your question about equipment the short answer is no.
Describing HOW your Acura is consuming oil would be beneficial to diagnosis. Smoking? When? Start up, WOT, trailing throttle, starting off after idling.... etc.

 

[Rusted Nut]

I’m not sure a tire inflator will have the capacity to perform a leak down. In most cases a leak down is better than a compression test. But in your case, a compression test may be better. If you’re burning oil, it’s either rings, valve guides, or if a DI engine carbon deposits keeping valves from closing all the way. Perform a compression test, then squirt a good bit of light oil in cylinder, and retest. If compression comes up, then your rings are worn. Try some fuel system cleaner, it may clean the valve deposits off. 130k is low mileage for worn out valve guides.

 

[YoshiMoshi3]

Thanks for the guidance. There is no abnormal smoke when driving. I measured it after about 3000 miles and was a quart low.

Does anyone have a procedure for a leak down test on this car? It's the 2.4 L, 4 cylinder Honda engine. I can't find the procedure in ShopKey.

 

[N8sToolz]

So a leak down test is measuring the volume of air that's lost in the cylinder, measured in percentage of regulated and measured. An inflator won't be able to produce enough volume to give you the information your looking for. You be better off with an inflator tank.

Also industry standard is 1 QT of oil lost per 1000 miles is perfectly acceptable, across all brands.

 

[charbar]

Thanks for the guidance. There is no abnormal smoke when driving. I measured it after about 3000 miles and was a quart low.

Does anyone have a procedure for a leak down test on this car? It's the 2.4 L, 4 cylinder Honda engine. I can't find the procedure in ShopKey.

Leak down procedure is basically the same on any engine regardless of make/model/engine. You WILL need a leak down tester and a steady stream of shop air. Simply adding air to a cylinder to a certain PSI and trying to somehow test if it loses pressure after a certain time is impossible. There is ALWAYS some leakage past the rings. Not even sure how you would rig up a tester for that. A check valve and a gauge I guess. Doesn't matter anyway because it literally is not a test for anything.

And in chamber combustion pressures are far higher than any shop air compressor is capable of getting too. You will never put 'too much' pressure to a cylinder with an air compressor. Hell even cranking compression on a good gas engine is higher than a lot of compressors are capable of.

If you really want to do a leak down test I would run to one of the auto parts stores that loan out tools and borrow one. Find a buddy with an air compressor if you don't have one. Honestly you are barking up the wrong tree trying to chase an oil consumption issue with a leak down tester though. Unless you have a hole in a piston

 

[WildBill]

Just run a can of this through it, cleans the gummed up rings. Almost completely stopped oil usage in my 2010 Scion, went from around 1.5 quarts every 3k miles to almost none. Maybe 1/8 quart every 3k now, not enough to have to add oil between changes anymore. Local Toyota dealer uses it on everything with oil usage complaints, works amazing. https://www.amazon.com/dp/B07TK27JF1?tag=atomicindus08-20

 

[dcg9381]

Gonna need a small compressor.

 

[YoshiMoshi3]

So a leak down test will not help me in determining why I'm burning oil?

I understand that 1 quart every 1000 miles is considered healthy. Hoping to see if it's fixable, so I don't have to check my oil so much, and one less thing to worry about.

If I passed the engine compression test with flying colors, would a gas additive, or oil flush help at all? I know there is a product called "Engine Restore", which increases compression, and I could easily measure the before and after to see if it worked. But I could good compression.

Thanks for all the help!

 

[u3b3rg33k]

So a leak down test will not help me in determining why I'm burning oil?

I understand that 1 quart every 1000 miles is considered healthy. Hoping to see if it's fixable, so I don't have to check my oil so much, and one less thing to worry about.

If I passed the engine compression test with flying colors, would a gas additive, or oil flush help at all? I know there is a product called "Engine Restore", which increases compression, and I could easily measure the before and after to see if it worked. But I could good compression.

Thanks for all the help!

when my car finally went past 2qt makeup/15k OCI, i had visible smoke on start-offs due to worn out valve guides.

maybe follow your own car while someone else gives it an Italian tuneup?

 

[N8sToolz]

Usually the sign is excessive blowby. You can check to see how much by open the oil cap while it's running. But it's more of a relative thing than something you can test for. Not sure if any manufacturers give a spec for that.

Check pcv system use a high quality engine oil and give it some spirited driving. You may be able to get some of the sludge trapped in the rings hot enough to release the rings. If they are straight up worn or broken the it won't do anything for you. It may take a few oil changes and some time to see a difference.

Its worked for me a couple times. I'd have vehicles burn 1qt at 1k and it got it down to every 4k. Castrol edge seem to work for me.

 

[richfinn]

Considering doing a leak down test on my 2014 Acura TSX that's burning oil. Am I able to do this test with a tire inflator or even a hand pump. I have done this before in school, but never at home. Can I just use a tire inflator or hand pump? I understand the basic operating principles. But the cylinder in top dead center so intake and exhaust valves are closed. Put in a new pressure into the leak down test tool. Set the pressure into the cylinder. Leave it for so many minutes and see if it hold the pressure.

I'm thinking that say the target is 135 psi. Can't I just use my Milwaukee M18 tire inflator so that it goes to 135 psi, then open the valve so that the pressure goes into the combustion chamber as well, resulting in the pressure going down, then re-run the tire inflator so it's 135 psi and see if it holds it.

Also when I have done this before I was able to find procedures in like ShopKey or AllData. But I'm not able to find a procedure for a leak down test in this car in ShopKey. I can't like for example find what pressure I should use. I don't want to use to much.

Thanks for all help!

You are going to need shop air to perform a proper leak down test, the leak down tester itself should have a pressure regulator and the gauge is usually calibrated to show leakage in a percentage format (at least the one I use is).

As others have said this might not be the best test for excessive oil consumption

 

[NHtoolguy]

If coked-up oil control rings may be the culprit, why not try Valvoline Protect and Restore oil for one oil change interval, and see if that helps? I've never used it, but the reviews I've read seem to suggest that it works. It must have some pretty strong detergent additives.

 

[BORING HOP YARD]

I use 100 lbs. of air feeding the leak down tester to keep it simple. The tester has two gauges; the inlet gauge is the amount of air pressure feeding the tester. In my case I use 100 lbs. of air. Rotate the engine to put the piston at TDC with both valves closed.
Turn the dial on the tester to put 100 lbs. of air into the cylinder, the second gauge on the tester tells you the amount of pressure that cylinder is holding. Let's say you have 100 lbs. going in and the 2nd gauges reads 80 lbs. this indicates your loosing 20 lbs. or 20 percent of pressure in that cylinder. This is why you need a 100 lbs. air pressure to be constant air pressure.
The thing I like most about the tester is what its telling me about where the 20 percent is going, Take off the intake filter and open the throttle and bend down and see if you can hear any hissing from air escaping the cylinder, if you don't hear anything go to the tail pipe and see if you can hear hissing if not take of the oil cap and see if you hear hissing. You should be able to hear and locate the hissing, if not the test is faulty. If you hear it at the throttle opening you have intake valves that are leaking, if you hear it out the exhaust you have a exhaust valve leaking and out of the oil cap opening its going by the rings.
As far as the oil rings I don't this will show the condition of the oil rings.
I worked in a race shop that built and maintained race cars. It was standard practice to leak test a brand new or rebuilt engine, document the results and then retest the engine after every race documenting the results. You could see the engine slowly start to loose cylinder pressure after a few races, when the pressure got down to the agreed apon value the engine would get pulled and rebuilt starting the process over again. 10 to 20 percent on a street motor was acceptable but once it got more than 25 percent it was recommended to get it rebuilt. One of our race customers wanted it rebuilt when it got above 10 percent. The vast majority of time we had about 5 to 7 percent lose over the season.

 

[Milton Shaw]

I had a Ford leaving a cloud after sitting at a long traffic light. Didn't leave a cloud on the road or driving ever. I found it was several stopped up oil drains in the back of the engine. The rear of the engine was lower than the front as on most V8's and oil would eventually at a light build up enough to overflow the valve oil seals on the back several cylinders on the stopped up side. Cleaned drains and flowed oil in squirt guns in the heads and never had a problem again with oil ponding in the back of the heads. Engine had 150K on it and was 15 years old at the time, but it was not using hardly any oil. Normal driving would slosh oil down the working middle and front drains and no smoke clouds.