Larry T.

I am looking (long distance) at a 930. I decided to have a PPI done prior to investing in the trip out to see the car. I just got the results of the leakdown test.

2%, 0%, 0%, 0%, 0%, 2%

I have never heard of 0% leakdown. Is this possible? I haven't spoken to the shop yet...I just wanted to get some input before I do.

Kevin

0% does happen. Did you ask what leakdown gauge was being used. Most shops will use a Snap On.

The engine must have had a topend overhaul recently. If it hasn't I would question the test, or at least ask for a gauge calibration.

911rudy

It sounds like one of those gages from Harbor Freight.

Larry T.

I did ask him about the numbers. Here is the response I got:

I have run in to this before with engines that are in perfect condition… I use a Snap On Leakage Tester. It is only a couple of years old and typically it will have a margin of error of +/- 2%... He got here about 9:30 AM and by the time I tested it, it was about 12:30 or 1:00… So it was warm. Keep in mind there was still oil coating the pistons and cylinders which will help sealing. Of course we are only looking at helping a fraction.

So, now I'm confused. I've never heard of 0% leakdown and the PPI shows 4/6 cylinders at 0%. FYI, the engine has 50K on it and no records of a top OH.

CaptainCalf

If the motor was recently re-ringed with a gapless #1/top compression rings then it's possible...RC

MUSSBERGER

I don't see how. What'd he do? Spray oil in each one before the test? And isn't the test to be done on a cold motor?

WERK-I

LOL! ......or paraffin?

Larry T.

I thought it was supposed to be done on a cold engine as well. What effect would it have if the engine was warm?

911rudy

Cars and women are alike. When they are probed cold and without heat and lubrication the true internal profile is available. But when heat and lubrication loosen things up the compression goes up to level that gives one a false since of well being.

six gun

Well Said !!

pu911rsr

I've seen 0% leakdown on fresh motors.
Phil