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

TrboSpdAnt 04-16-11 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 04-16-11 06:18 PM

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

Monkman33 04-16-11 07:32 PM

Exactly what it sounds like.

arghx 04-16-11 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 04-16-11 07:39 PM

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

TrboSpdAnt 04-16-11 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 04-16-11 11:12 PM

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

TrboSpdAnt 04-17-11 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 04-17-11 12:35 AM

omg....

Gringo Grande 04-17-11 12:43 AM

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

therotorrooter 04-17-11 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 04-17-11 09:42 AM

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

TrboSpdAnt 04-17-11 10:41 AM

Well, yes; this is true.

TrboSpdAnt 04-17-11 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 04-25-11 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 04-25-11 11:31 PM

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


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