nice day out. lets do leakdown!
04-02-2012, 10:38 AM
#1
2 Props,3 Dildos,& 1 Cat
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nice day out. lets do leakdown!
So I was going to do an oil change and I thought HEY I smell coolant under hard acceleration! I should call Braineack and tell him to come over with his leakdown tester just so I can sleep at night and not feel like I wasted an oil change.
we used the crappy compressor hestole got from work back in the day. It tripped my circuit breaker twice. But it provided pressure and that's what matters, RIGHT?
Popped the hood on the pollen-colored miata and spent some time watching Brainy tell me I had 99% leakdown in #1 before he realized he was not at #1 TDC Compression, but TDC Exhaust. i.e. valves open.
Once he swapped the hose to #4 which was at TDCC, we took readings:
cyl# pressure in/pressure held (leakdown %)
#1 80/77 (3.7%)
#2 100/96 (4.0%)
#3 60/59 (1.7%)
#4 80/77 (3.7%)
my motor is a stock 2001 with about 100k and about 2/3 of those miles turbocharged.
results: me, happy.
now I gotta pressure test my cooling system...
we used the crappy compressor he
Popped the hood on the pollen-colored miata and spent some time watching Brainy tell me I had 99% leakdown in #1 before he realized he was not at #1 TDC Compression, but TDC Exhaust. i.e. valves open.
Once he swapped the hose to #4 which was at TDCC, we took readings:
cyl# pressure in/pressure held (leakdown %)
#1 80/77 (3.7%)
#2 100/96 (4.0%)
#3 60/59 (1.7%)
#4 80/77 (3.7%)
my motor is a stock 2001 with about 100k and about 2/3 of those miles turbocharged.
results: me, happy.
now I gotta pressure test my cooling system...
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04-02-2012, 11:56 AM
#4
2 Props,3 Dildos,& 1 Cat
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constant air supply to the regulators from the tank. ideally the air source (compressor) should provide a steady 120 psi for your 100 psi setting on your inlet regulator.
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04-02-2012, 11:57 AM
#5
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instantly. once the clyinder was ready, I just started turning up the **** and pressurizing the chamber. How else would you do it?
btw, my compressor only holds 100psi max and the power outlet was being shared by y8s's wife at the time, so thats why the readings are all over the place for reference pressure.
but still, they were holding fine. I was consistently seeing 12% leakdown on my motor with the same gauge and method.
btw, my compressor only holds 100psi max and the power outlet was being shared by y8s's wife at the time, so thats why the readings are all over the place for reference pressure.
but still, they were holding fine. I was consistently seeing 12% leakdown on my motor with the same gauge and method.
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04-02-2012, 12:15 PM
#9
instantly. once the clyinder was ready, I just started turning up the **** and pressurizing the chamber. How else would you do it?
btw, my compressor only holds 100psi max and the power outlet was being shared by y8s's wife at the time, so thats why the readings are all over the place for reference pressure.
but still, they were holding fine. I was consistently seeing 12% leakdown on my motor with the same gauge and method.
btw, my compressor only holds 100psi max and the power outlet was being shared by y8s's wife at the time, so thats why the readings are all over the place for reference pressure.
but still, they were holding fine. I was consistently seeing 12% leakdown on my motor with the same gauge and method.
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04-02-2012, 12:19 PM
#10
Boost Czar
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still don't quite understand. you don't ever stop feeding it pressure, it's a constant supply of X pressure, and a constant reading of Y in the second gauge (which reads the clyinder).
thread now has a pic!
thread now has a pic!
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04-02-2012, 01:20 PM
#11
2 Props,3 Dildos,& 1 Cat
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the idea is to find out how big that leak is by measuring the pressure before a calibrated "leak" orafice and then before your engine's leaky sealing surfaces.
imagine filling a bicycle tire with your compressor. but the tire has a hole in it.
the leak down tester has two gauges, a... wait I will google a picture.
the orafice maintains a limited flow rate between the two gauges to keep the inlet pressure up and allow the engine's leaking to determine the second gauge pressure reading. if there are no engine seal leaks, both gauges read identical numbers. realistically, even the tightest engine will read some nominal leakdown but get very close to 100%.
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