jayrq2o1
New member
boost leak test
Okay, cobbled together a boost leak tester from a coupler and cap that I picked up from Lowes. Slipped it over the turbo inlet and pumped in 23 lbs. There is a barely, and I mean very barely audible sound of air coming from the head. It's clearly not in the engine bay from various methods I used to try and find a leak.
Tried plugging the driver side charge tube and then started pumping the 23 lbs and eventually air just started escaping over the poorly made plug I made. But it held up to 19 lbs and the rest of the charge pipes and IC didn't show any bubbles on soapy spray.
Then slipped the coupling over the throttle body and its that very, very low sound of air again. I sprayed soapy water all over the throttle body to see if there were any bubbles, but none appeared. I've posted this question on facebook, but I'll ask it here too just in case.
I'm attributing the sound of air to one of three things.
A) The valvetrain can overlap due to the motor having variable cam phasing. Therefore, the air is escaping through the exhaust while both valves are open.
B) The air is simply finding a pathway to the crankcase and escaping via the PCV. When I stick my finger in the PCV dump location at the turbo inlet, the pressure doesn't really hold any more than before I do, but upon removing my finger, there is a very audible POP.
C) The 23lbs I'm pumping into the throttle body is JUST enough to crack the exhausting cylinder's intake valve open and is slowly escaping through the exhaust.
I guess there's an easy way to deduce and eliminate some of these, but I just did the test quickly on my 30 min lunch break.
Thanks in advance!
Okay, cobbled together a boost leak tester from a coupler and cap that I picked up from Lowes. Slipped it over the turbo inlet and pumped in 23 lbs. There is a barely, and I mean very barely audible sound of air coming from the head. It's clearly not in the engine bay from various methods I used to try and find a leak.
Tried plugging the driver side charge tube and then started pumping the 23 lbs and eventually air just started escaping over the poorly made plug I made. But it held up to 19 lbs and the rest of the charge pipes and IC didn't show any bubbles on soapy spray.
Then slipped the coupling over the throttle body and its that very, very low sound of air again. I sprayed soapy water all over the throttle body to see if there were any bubbles, but none appeared. I've posted this question on facebook, but I'll ask it here too just in case.
I'm attributing the sound of air to one of three things.
A) The valvetrain can overlap due to the motor having variable cam phasing. Therefore, the air is escaping through the exhaust while both valves are open.
B) The air is simply finding a pathway to the crankcase and escaping via the PCV. When I stick my finger in the PCV dump location at the turbo inlet, the pressure doesn't really hold any more than before I do, but upon removing my finger, there is a very audible POP.
C) The 23lbs I'm pumping into the throttle body is JUST enough to crack the exhausting cylinder's intake valve open and is slowly escaping through the exhaust.
I guess there's an easy way to deduce and eliminate some of these, but I just did the test quickly on my 30 min lunch break.
Thanks in advance!
