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paulv · 12-28-2012, 04:59 AM

Bala,

You're almost there. It is imperative that both valves in the cylinder under test are closed -- so TDC or BDC. It is better to test with TDC but some people have safety concerns and use BDC. I always go with TDC and leave the car out of gear (or in park). haven't had the need to do this with my Box, but helped out a couple of friends with their junk cars.

Here are the items required for your testing:

Throttle body open -- allows for hearing leaks from a bad intake valve(s).
Exhaust system (obviously open) -- allows for hearing leaks from a bad exhaust valve(s).
Remove oil dipstick -- allows for hearing leaks into the crankcase from blowby caused by bad rings.
Coolant fill cap -- allows for seeing bubbles in the coolant caused from cracked head/headgasket/etc.

Regards,
paul...

12-28-2012, 04:59 AM	#7
paulv Registered User Join Date: Apr 2006 Location: Boston, MA Posts: 221	Bala, You're almost there. It is imperative that both valves in the cylinder under test are closed -- so TDC or BDC. It is better to test with TDC but some people have safety concerns and use BDC. I always go with TDC and leave the car out of gear (or in park). haven't had the need to do this with my Box, but helped out a couple of friends with their junk cars. Here are the items required for your testing: Throttle body open -- allows for hearing leaks from a bad intake valve(s). Exhaust system (obviously open) -- allows for hearing leaks from a bad exhaust valve(s). Remove oil dipstick -- allows for hearing leaks into the crankcase from blowby caused by bad rings. Coolant fill cap -- allows for seeing bubbles in the coolant caused from cracked head/headgasket/etc. Regards, paul...