How to perform a Leak Down Test on a LS1?
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How to perform a Leak Down Test on a LS1? Ok I have pretty much done everything you can do to these motors but there are a few things I have not done like this and cams 
so I want to get the correct info before I jump on them. As some know I have a motor that is burning oil with less then 600miles. I want to do a leak down test on all cylinders before I take it back to the builder.
Can you give me the steps to perform this correct and all tools needed.
so I want to get the correct info before I jump on them. As some know I have a motor that is burning oil with less then 600miles. I want to do a leak down test on all cylinders before I take it back to the builder. Can you give me the steps to perform this correct and all tools needed.
You need a leak down tester tool. Remove one plug at a time, move the piston to TDC, apply air with the leak down test and read the gauge. Very easy. Write down all of your readings and you are all done.
Listen for where the air is going if it is leaking badly. 10%-15% is OK as guages will vary etc.. If you hear air in the exhaust bent or burned exhaust valve. If you hear it in the intake or coming out TB ditto intake valve. Coolant bubbling is HG and hissing in the dipstick tube or valve cover area is ring.
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Verdad Gallardo I just did mine, had severe blow by, had 85% leakage on 5 and 7. Pushing air out the oil filler cap like old faithful. Pulled it down, broken ring lands on both. New pistons and a cam upgrade are now in process. Heck, the times in my sig are from the day it went, can't wait to see how it runs on all 8 and a better cam.
Don't forget the 4 stroke cycle has two TDCs. You have to be on the right TDC. Be SURE piston is EXACTLY at the top to reduce the chance that the compressed air will push the piston down(keep hands out of harms way as quick connect is plugged in). Listen for excaping air at:
Tail pipe
Mouth of throttlebody(blade blocked open[unless your drive by wire] w/plenum removed
Oil filler cap
Cooant resevoir tank(cap removed)looking for air bubbles.
Lower leakage is better, but don't expect 0%.
Tail pipe
Mouth of throttlebody(blade blocked open[unless your drive by wire] w/plenum removed
Oil filler cap
Cooant resevoir tank(cap removed)looking for air bubbles.
Lower leakage is better, but don't expect 0%.
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Ok so
1. Bring it up to operating temp
2. Put motor on TDC
3. Remove plug and insert leak test gauge
4. Record leakage %
5. Remove next plug and perform the same tasks.
Is that all correct?
1. Bring it up to operating temp
2. Put motor on TDC
3. Remove plug and insert leak test gauge
4. Record leakage %
5. Remove next plug and perform the same tasks.
Is that all correct?
Doesn't have to be super hot just warm IMO, move each piston to TDC as you test. Don't be suprised to see up to 10% leakage.
I have a INSANE way of fixing oil burning like you have. You do it without disassembling the engine. I'm not gonna post it up here because there are too many people who will say this and that about it but if you want to know i'll pm the info to you. I used it on my Harleys when i had similar trouble like this.
I have a INSANE way of fixing oil burning like you have. You do it without disassembling the engine. I'm not gonna post it up here because there are too many people who will say this and that about it but if you want to know i'll pm the info to you. I used it on my Harleys when i had similar trouble like this.
Doesn't have to be super hot just warm IMO, move each piston to TDC as you test. Don't be suprised to see up to 10% leakage.
I have a INSANE way of fixing oil burning like you have. You do it without disassembling the engine. I'm not gonna post it up here because there are too many people who will say this and that about it but if you want to know i'll pm the info to you. I used it on my Harleys when i had similar trouble like this.
I have a INSANE way of fixing oil burning like you have. You do it without disassembling the engine. I'm not gonna post it up here because there are too many people who will say this and that about it but if you want to know i'll pm the info to you. I used it on my Harleys when i had similar trouble like this.
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I think it might have been a little over reacting from my wife I don't know because I never seen the smoke or anything so you never really know. I do know she checks the oil before everytime she drives it from now on and seems the last few days it has stoped.
Women