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-   -   Awesome compression test! (https://www.rx7club.com/3rd-generation-specific-1993-2002-16/awesome-compression-test-950571/)

TrboSpdAnt Apr 16, 2011 06:12 PM

Awesome compression test!
 
So... did a compression test on an engine today....

What's a psi reading of (LITERALLY) 0 mean? :lol:

MR_Rick Apr 16, 2011 06:18 PM

Hey start selling paper weights. The rotor in my sig came out of my 1st gen. Yeap pretty door stop.

Monkman33 Apr 16, 2011 07:32 PM

Exactly what it sounds like.

arghx Apr 16, 2011 07:34 PM

Are you sure you did it right? Was the tester screwed in properly? If you crank it over without the tester in the plug hole, can you hear compression sounds? Do you feel any resistance during the compression stroke when you turn the engine over by hand?

Japan2LA Apr 16, 2011 07:39 PM

Sounds like you" Replacement engine needed" light is on...

TrboSpdAnt Apr 16, 2011 08:07 PM

Now that we've gone through the 'helpful' responses.. Not to mention the, "No shit," ones...

Front tested and got numbers (not relevant) and replaced plug in hole to verify presence of air-pressure (or lack there-of) from rear.

The question here is what (specifically) would cause a '0' reading on a rotor.

greenday_5606 Apr 16, 2011 11:12 PM

Apex seals. What the hell did you put the motor through?

TrboSpdAnt Apr 17, 2011 12:08 AM

That would have to be ALL 3, to read '0' psi, though, right?

When I say '0' I mean LITERALLY 0psi, not 'like' 0psi.

Humorously enough, it starts and drives, still! Thing's got fucko for low-end and still boosts (as far as the manifold is concerned, anyway) and I'm told it sounds like a Pod-Racer starting up, at a couple points in the tach.

theo481 Apr 17, 2011 12:35 AM

omg....

Gringo Grande Apr 17, 2011 12:43 AM

Is this the digicamo or red pill? Mark needs to invest in some AI.

therotorrooter Apr 17, 2011 12:54 AM

When an apex seal broke, rolled out, blew out, whatever, it probably took the other two with it. It can happen. Probably trashed the rotor, housing, and plate(s). Yeah, it can still run...obviously only building pressure in the good chamber, but yeah it will sound like hell and have little to no power... that sucks.

Monkman33 Apr 17, 2011 09:42 AM

it only takes 2 bad apex seals to have no compression on all three faces.

TrboSpdAnt Apr 17, 2011 10:41 AM

Well, yes; this is true.

TrboSpdAnt Apr 17, 2011 05:00 PM

@Gringo: Red Pill.

Mark HAS AI - Ant Intelligence... :lol:

@hondasr4kids: Yea, they do. I've got 3, already. 2 are going to be acid-dipped and polished. The other one was just semi-polished.

Great for office desk pen-holders and door stops!

Carl Apr 25, 2011 10:42 PM

The Mazda compression tester will read 0 if the reading is less than about 3 kg/cm2. That is what it says on the side of the tester. My 12a also ran fine (but wouldn't start) with 0 indicated compression. That's probably what happened. Also means the motor is dead I would say.

Carl

TrboSpdAnt Apr 25, 2011 11:31 PM

LOL. Yeah, I knew that about the compression tester (minimum reading), but my vote is the latter.


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