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-   -   Time for a Rebuild? (compression test video) (https://www.rx7club.com/new-member-rx-7-technical-256/time-rebuild-compression-test-video-948830/)

Butter Mittens 04-04-11 07:14 PM

Time for a Rebuild? (compression test video)
 
I'd like to start off by saying that I am a new member and I grateful for all of the support that I have already gotten from other members on the forum. Thanks everyone!

I have had the car for about a week now and have already tore the car to pieces (don't worry, its back together now)! Dash has been out and back in (speedo fix), door panels off and on (stereo installer was a butt connector fiend; ughh...) but I have gotten mixed input when it comes to compression pressure ranging from 75psi to 125psi. I have been doing a ton of research in regards to bushing as the car REALLY needs them but now I'm wondering if I should just save up for a rebuild. The car runs well and pulls hard with a perfect boost pattern. Only complaints are a unpredictable idle (probably an injector or a vacuum hose that I haven't come across yet), the 30 seconds of white smoke at start-up and the rich/gas smell for the first minute or two after start-up (this is also when the idol starts to even out). The car still has pre-car and cat with only a catback. Is it possible for the stock ECU to run rich?

I have posted a video of the compression test I did today below. Thanks in advance for any input. I really appreciate it.

http://www.youtube.com/watch?v=CpeJ8iC7YWU

BomberMan 04-04-11 09:39 PM

Looks good to me. I forget whether the compression should be 30 or 60 psi per rotor face when testing the faces one at a time. But the total compression (built up with the button out) will range from about 90 to 110 psi Whereas 115 is like new and 85 is effectively blown and will need a helluvalot of foreplay to get it started. Check this:

http://www.rotaryresurrection.com/2n...ion_check.html

Butter Mittens 04-05-11 05:35 PM


Originally Posted by BomberMan (Post 10553489)
Looks good to me. I forget whether the compression should be 30 or 60 psi per rotor face when testing the faces one at a time. But the total compression (built up with the button out) will range from about 90 to 110 psi Whereas 115 is like new and 85 is effectively blown and will need a helluvalot of foreplay to get it started. Check this:

http://www.rotaryresurrection.com/2n...ion_check.html

Thanks Bomber! Thats great information.

I have actually read through the Rotary Resurrection compression page a couple times. It does say to look for "30-35 psi" while "holding down the valve on the side of the tester" (relief valve). I have actually removed the schrader valve so that it isn't necessary to hold down the relief valve on the side of the gauge. This is also supposed to yield higher pressure when doing the test. Has anyone done a compression test with a standard compression tester, removed the schrader valve and know what compression to look for in PSI when watching the needle bounce for each rotor face?

Thanks again for the input, Bomber.


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