im about ready to send my turbo out for a rebuild if possible. i cant afford a rebuild right now. would a leakdown test be a reliable way of figuring out the health of my motor? my compression test results werent that great 150-155 across the board. however, my motor still runs with the exception of the bogging, which might be related to the blown turbo. i was wondering if a leakdown test would be a reliable way of finding out if my headgasket was still ok and if the head (valvatrain especially) is in good shape to boost.

 

Yea, a leakdown test would be your best bet as it will tell you anything from rings to valves. Typically I don't like anything over 5% leakdown but that's after a complete rebuild so I guess those would tend to be the lower numbers. If you are unsure of the leakdown steps here they are. Set each cylinder at TDC just as you would when doing a valve adjust and pressurize the cylinder. Sometimes once you connect the air it will rotate the crank so make sure it doesn't move (you will know if it does). Excessive air flowing out the breather (or vented catch can if you have one) indicates worn rings and the like. Air flowing out the IN or EX manifold will let you know the valves aren't sealing for some reason, and lastly if you pop off your radiator cap and notice bubbles floating up look into the headgasket. Hope this helps and Good Luck

 

thanks.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Kataku2K3 &raquo;</TD></TR><TR><TD CLASS="quote">Yea, a leakdown test would be your best bet as it will tell you anything from rings to valves. Typically I don't like anything over 5% leakdown but that's after a complete rebuild so I guess those would tend to be the lower numbers. If you are unsure of the leakdown steps here they are. Set each cylinder at TDC just as you would when doing a valve adjust and pressurize the cylinder. Sometimes once you connect the air it will rotate the crank so make sure it doesn't move (you will know if it does). Excessive air flowing out the breather (or vented catch can if you have one) indicates worn rings and the like. Air flowing out the IN or EX manifold will let you know the valves aren't sealing for some reason, and lastly if you pop off your radiator cap and notice bubbles floating up look into the headgasket. Hope this helps and Good Luck</TD></TR></TABLE>

Well said. Unfortunately I have experienced your leakdown skills first hand