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-   -   Help! (https://www.rx7club.com/1st-generation-specific-1979-1985-18/help-438804/)

jfaplanet 06-29-05 01:41 PM

Help!
 
OK, here's the deal, I got a 1st gen 85 GSL. Stock 12A, all original, 134k miles. Its got some problems. I've changed carbs, checked igniters, coils, cap, wires, plugs, pulled the cats off, checked timing, its 0 top dead center for # 1 leading, and still it won't make any power. It will start and idle at about 1500 rpms, but I can't find any vacuum leaks. I've even given it an alternate fuel source and it still does the same thing it did with the original carb. The only thing I haven't done is a compression check, but when it runs it don't shake or act like its lost a rotor. Anybody with any ideas please post so I can try to figure out whats wrong with this beast. I'm ready to get the 357 out and put it down. Thanks in advance, REPU-Charlie

SUPEROTARYPOWER 06-29-05 02:00 PM

Everyone seems like they dont like the rotary or something, always so quick to replace it with a Piston motor? Go get a Piston car then! HAHAHA Just kiddin!!! I hope i can help as i would like to see you keep the rotary in the car....

#1 pull all spark plug wires-----remove the leading plug and connect a Compression test guage... Test it cranking and Record the three readings you recieve...Then do it again and see if the readings are still the same.... Then put back that first leading plug and do the same for the rear plug....
#2 after you got hopefully good readings let me know what they say
#3 Next your distributor is able to time itself you said correctly? Leading and Trailing are properly seperated by 8 degrees?
#4 If approaching your engine from the passenger side..look at the lower left hand side of your intake manifold there should be a slightly large hole see if its blocked and covered.
#5 Sounds alot like a Vacuum Leak your symptoms
#6 Re-Tuning your carb....Turn the small adjusting screw in all the way and remove it out 2-2 1/2 turns. You can go less if you want minimum to 1 1/2... Then re-adjust your throttle cable so make sure they throttle plates are securely closed...The screw also that adjusts the idle should be out all the way and then you can increase it till the car runs and then increase it more to your desired 700-800 Rpm Idle.

Elysian 06-29-05 02:34 PM

sounds like apex seals to me, my 74 repu didn't vibrate or anything when the rear rotor went, it just made crap for power...

slashdawg00110 06-29-05 03:09 PM


Originally Posted by SUPEROTARYPOWER
Everyone seems like they dont like the rotary or something, always so quick to replace it with a Piston motor?

I don't think he was talking about replacing the rotary engine with a piston engine. The 357 would kill the 12A rather than replace it.

Good advice though.

Rx7carl 06-29-05 04:45 PM

Low compression is not obvious just by looking at it. Id suggest decarbonizing and a compression check as a starting point.

Fire85GSLSE 06-29-05 07:22 PM


Originally Posted by Rx7carl
decarbonizing .

How is that done?

91TII 06-29-05 07:39 PM

Well ,I have spoke to him and his car has good Apex seals. They are all there with no chunks missings.
The Distributor and timing marks all check out fine.

I don't know what this is -- (FI person - Not too many carb motors)
#4 If approaching your engine from the passenger side..look at the lower left hand side of your intake manifold there should be a slightly large hole see if its blocked and covered.


He has no Vacuum leaks. He did spray starter fluid around the base of the carb and the nest with no changes.

Check this out,
Could he have a problem with the apex seals sticking? (Pushed in the rotor)
That would explain his hard starts and lack of power.


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