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-   -   New to Rotaries (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/new-rotaries-500219/)

TX86RX7 01-17-06 01:18 AM

New to Rotaries
 
Well I just picked-up my first RX7 last week. It's an 86 GXL with 170K miles. Currently it's not running; the previous owner said it was due to the lack of compression. So after reading thread after thread on here, I did the compression test. During the test, the front rotor initially registered 20 on all 3 sides, then after awhile, it went up to 100 on all 3 sides and stayed there. The rear rotor also initially tested at 20 on all 3 sides and finally settled at 50. I did 3 full revolutions per rotor (10-15 seconds). I know it sounds like I had some stuck seals; since the previous never started/cranked the motor in almost a year. Here's my question:
-Should I try doing the ATF/OIL trick to see if I can get her started; since I have great compression in the front and mid-compression in the rear or should I just stop everything and start my rebuild (to avoid damaging the rotors/housings)?
-Also, when I pulled the plugs out I noticed that I had a mild brown liquid build-up on my plugs (strong gas odor with some texture).

Can someone clarify these issues for me:
-I read in 1 post that our motor will run on 1 good (compression) rotor; is this true?
-In doing the ATF trick, do I put the lube in the leading or trailing plug holes (I've read threads mentioning both, just the trailing and just the leading...very confusing).

Thanks in advance.

eriksseven 01-17-06 02:11 AM

Well, it's probably not a great idea to actually *start* the motor up, if AFTER an ATF treatment the compression is still 50psi in the rear. Do the ATF treatment, rotate the motor, let it soak, inject more, rotate more. You'll want to inject the ATF into the lower plug-holes, because the actual 'hole' is a lot bigger (that actually goes through to the motor). You'd have to take a look at some housings (from the inside) to really see what I'm talking about.

A rotary will run on one rotor, but it will be hell to start and it will run TERRIBLY. Not to mention, if something is fubared in the rear-housing, you probably don't want to be spinning it more than a couple hundred RPM's. ;)

If you're sucessful in getting around 90psi+ all around, then before you attempt to start it, you should siphon out all your gas (there are tricks to doing this) and put in some fresh fuel. As well as putting some new plugs in there and setting your timing.

BTW, the jacked up plugs are probably due to carbon-build up/fuel residue.

Regardless, you should plan on a rebuild.

eastcoastdrift 01-17-06 02:15 AM

I agree, i would start the rebuild as soon as possible. Maybe even before you try and start it, just to be safe.

Carzy Driver 01-17-06 02:17 AM

yes our cars will run on only 1 rotor, but not going the engine any good. put some ATF into the leading plug hole, the bottom one, because the trailing hole inside is ~ 1/8" wide. and with the strong odor of gas, did you pull the EGI fuse, the one inside the engine bay and unplug the CAS that way there will be no sparkplugs firing

TX86RX7 01-17-06 11:22 AM

Thanks for everyone's input. I think I'll just start the rebuild and get it over with.

prjct87rx7 01-17-06 05:47 PM

that a boy!

NeCr0mStR 01-17-06 07:21 PM

word to the wise
 
I started the same way you did with a bad motor... if your planning on rebuilding it yourself a couple things to consider are this... If there is damage inside and you get it apart and need parts. It may be more work to rebuild it yourself and also as expensive as just buying a rebuilt motor. And if you have taken it apart (not that I am an expert so correct me if I am wrong) but I don't know if any shop you wanna buy a motor from will take yours for core after you have cracked it open.

Just a little advice, since I opened my motor up and found a apex seal in 5 or 6 pieces and one of the side housings and rotors completely destroyed, which was going to be VERY expensive to fix and fix proper. I don't like half arseing anything or hoping I get it right.


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