boost leak test results in air out dipstick

**J&H Ryan** · 07-31-2010, 06:07 PM

Before I have the engine torn down, this sould like it prettymuch has to be rings or broken piston? I'm going to ask them to do a compression test (they don't want to do a leakdown with the engine in the car since its semi-dangerous regarding the new paint. The engine only had 2000 miles but maybe not enough oil made it around the rings in storage?

**turbovanman²** · 07-31-2010, 06:10 PM

Ok, so how is the dipstick being blown out, driving or pressurizing the IC system?

How does a leakdown test damage paint but a compression test won't?

**J&H Ryan** · 07-31-2010, 06:58 PM

Pressurizing it via the turbo intake. Paint: just regarding if the handle on the crank let loose.

**DodgeZ** · 07-31-2010, 08:15 PM

pull the PCV off of the valve cover and see if it is leaking. How is your PCV set up?

**BadAssPerformance** · 07-31-2010, 08:23 PM

+1 to PCV as a possibility...

**turbovanman²** · 08-01-2010, 12:52 AM

Originally Posted by J&H Ryan

Pressurizing it via the turbo intake. Paint: just regarding if the handle on the crank let loose.

WTF? why are you putting a handle on the crank? You set at each cylinders TDC and pressurize, you don't HOLD the crank with anything.

**BadAssPerformance** · 08-01-2010, 01:11 AM

If the slug is not exactly at TDC the air can blow it down... but should be able to hold it and do the test, maybe an extra set of hands?

**turbovanman²** · 08-01-2010, 02:14 AM

Originally Posted by BadAssPerformance

If the slug is not exactly at TDC the air can blow it down... but should be able to hold it and do the test, maybe an extra set of hands?

Never had a problem setting at each cylinders TDC and applying air, slowly. You don't want to hold it, it can quickly get out of control and you end up trapping your fingers,

**J&H Ryan** · 08-01-2010, 10:42 AM

Originally Posted by BadAssPerformance

+1 to PCV as a possibility...

I knew there was something I was overlooking.

I'm not doing the tests, the shop is. I was lost at the crank thing too as I could do leakdowns by myself with no issue. I'm trying to enjoy my vacation despite having a car with two powertrain issues (see trans thread) and I'm hoping jt is onto something.

**BadAssPerformance** · 08-01-2010, 12:16 PM

Originally Posted by J&H Ryan

I knew there was something I was overlooking.

I'm not doing the tests, the shop is. I was lost at the crank thing too as I could do leakdowns by myself with no issue. I'm trying to enjoy my vacation despite having a car with two powertrain issues (see trans thread) and I'm hoping jt is onto something.

Thanks, but I cannot take all the credit, was "+1-ing" DodgeZ

**J&H Ryan** · 08-01-2010, 04:17 PM

Originally Posted by BadAssPerformance

Thanks, but I cannot take all the credit, was "+1-ing" DodgeZ

Whoops, sorry dodgez. Trying to browse on a moto droid and missed the post.

**J&H Ryan** · 08-02-2010, 01:34 PM

From shop:

cyl 1-3 at 120psi, and #4 at 115. Leakdown on #4 was 65% leakage. Would that cause the car not to boost though? I mean, I'm getting 1-2 lbs max. No strange noises, ect...

Car has good power considering no boost, no smoke, ect... They want to tear the motor down, but that doesn't seem enough to go by - or is it?

**J&H Ryan** · 08-03-2010, 07:29 PM

Any thoughts or reccomendations?

**turbovanman²** · 08-03-2010, 07:32 PM

Did they test it hot?

Compression readings are ok, stock is 150ish, 100 is usually time to do it. 65% is alot but even with 120psi, you should have no problem building boost. Did they say the air was coming out of the crankcase when testing?

Sure, a rering wouldn't hurt, easily done in the car BUT a big but, if your doing this to fix it not building boost, this isn't the issue, unless you have a leaking valve or burn't valve but the readings don't indicate that.

**J&H Ryan** · 08-03-2010, 07:38 PM

OK, that's what I needed. I'm just trying to get this setup to work a year or two as is. Ill just have him look into the boosting issue then.

Afaik, its being done cold, not positive, ill ask.

**J&H Ryan** · 08-03-2010, 07:38 PM

OK, that's what I needed. I'm just trying to get this setup to work a year or two as is. Ill just have him look into the boosting issue then.

Afaik, its being done cold, not positive, ill ask.

**turbovanman²** · 08-03-2010, 07:48 PM

Originally Posted by J&H Ryan

OK, that's what I needed. I'm just trying to get this setup to work a year or two as is. Ill just have him look into the boosting issue then.

Afaik, its being done cold, not positive, ill ask.

Cold will show more leakdown.

**J&H Ryan** · 08-03-2010, 07:53 PM

He's stumped on the boost issue, I'm thinking with the compression not being hot and the cast pistons, might be time for a rebuild...

**DodgeZ** · 08-03-2010, 08:03 PM

Originally Posted by J&H Ryan

He's stumped on the boost issue, I'm thinking with the compression not being hot and the cast pistons, might be time for a rebuild...

big boost leaks are hard to find. You can't hear them. I had one so big on SRT it wouldn't build any pressure on the tester. I couldn't find it by sound. It was hot out and I felt cold air while the tester was running. I'd take the intercooling piping off and check it. If you have one of those 1piece T1 turbo to TB hoses toss it on to rule out intercooler/intercooler piping. How is your PCV system hooked up?

**turbovanman²** · 08-03-2010, 08:11 PM

Originally Posted by J&H Ryan

He's stumped on the boost issue, I'm thinking with the compression not being hot and the cast pistons, might be time for a rebuild...

Build a tester out of pcv, then block it at the tb end and pressure from the turbo using the leakdown tester.

How are you controlling boost?

Did you try the wastegate to the intake manifold trick?

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