1st Generation Specific (1979-1985) 1979-1985 Discussion including performance modifications and technical support sections

some advice please

Thread Tools
 
Search this Thread
 
Old Mar 11, 2007 | 09:41 AM
  #1  
mazdaverx713b's Avatar
Thread Starter
Have RX-7, will restore
Veteran: Army
Tenured Member: 20 Years
Loved
Community Favorite
iTrader: (91)
 
Joined: Oct 2003
Posts: 22,577
Likes: 1,273
From: Ohio
some advice please

recently i've been trying to get my 82 GSL up and going and i've had no luck. the problem i'm having is when i am attempting to accelerate from a stop, the engine bucks and tries to stall. at lower rpm's it totally runs like crap and will sometimes buck through the rev range below 4K. it will hold a PERFECT idle all day. i initially thought it was a clogged primary jet in the carb but yesterday i swapped carbs and the problem didnt do away. everything is still the same. i can definatly see that the carb is spraying more fuel, but like i said, no change. i have replaced the following parts: plugs and wires (both NGK), cleaned up the cap, new rotor, fuel filter, used but good carb, leading ignitor, leading coil, i've got a can of seafoam in the tank and fresh gas in the tank. i was thinking of trying another fuel pump today. i have a spare thats just sitting. maybe the pump loses pressure under load. i don't know. the timing i am assuming is ok because you can see that the distributor hasn't been touched, the engine temps are ok, and the locking bolt doesn't have a mark on it. could it be that i'm losing spark under load? should i go ahead and replace the trailing ignitor and trailing coil? i'm heading out in an hour or so and i'll be checking back before i go. if i dont hear anything, i'm just going to start with the fuel pump and move to the ignitor and then the coil. i'll post back what i find out.
Reply
Old Mar 11, 2007 | 01:41 PM
  #2  
Midwest 7's's Avatar
sellout
Tenured Member 15 Years
iTrader: (4)
 
Joined: Jan 2005
Posts: 3,078
Likes: 0
From: Lawrence KS
i think the igniters either work or they dont, i dont think you can have a weak igniter.
Reply
Old Mar 11, 2007 | 01:58 PM
  #3  
Rotary-MG's Avatar
the name is Stan
Tenured Member 15 Years
iTrader: (1)
 
Joined: Jun 2001
Posts: 340
Likes: 6
From: Sunny So. Calif
I bought a '84 SE real cheap because it had the same sort of problem. The accelerator pedal had a mind of its own. This forum lead me to replacing the Throtle Position Sensor (TPS) and once adjusted with the homemade indicator light, things where perfect since then.

Taking an Ohm meter the the TPS will tell you if it is bad or not. See if the readings go up smooth, or jumps around like mine did.

edit:
oh wait, you said '82, that would NOT have injection. So please disregard......
Reply
Old Mar 11, 2007 | 10:28 PM
  #4  
mazdaverx713b's Avatar
Thread Starter
Have RX-7, will restore
Veteran: Army
Tenured Member: 20 Years
Loved
Community Favorite
iTrader: (91)
 
Joined: Oct 2003
Posts: 22,577
Likes: 1,273
From: Ohio
changed the fuel pump, swapped out carbs( better but with an erratic idle), installed a new trailing coil and ignitor(for good measure) and after reinstalling teh old carb, i came to the conclusion that the carb is a bit bad. i have a perfect idle and the car runs amazing at rest and higher rpm, just not in the lower rev range and it buck at times while driving. what are the odds that there is a ton of junk in with the floats and i'm constantly sucking it up when i hit the throttle? is there a way to remove the top of the carb and clean out under the floats without completely disassembling the carb?
Reply
Old Mar 12, 2007 | 05:02 AM
  #5  
Kentetsu's Avatar
Lives on the Forum
Tenured Member 15 Years
 
Joined: Jun 2004
Posts: 11,359
Likes: 14
From: Grand Rapids Michigan
Verify that you have good spark on both leading and trailing, then start checking for vacuum leaks. Also, make sure that the carb spacer is installed correctly.
Reply
Old Mar 12, 2007 | 05:07 AM
  #6  
mazdaverx713b's Avatar
Thread Starter
Have RX-7, will restore
Veteran: Army
Tenured Member: 20 Years
Loved
Community Favorite
iTrader: (91)
 
Joined: Oct 2003
Posts: 22,577
Likes: 1,273
From: Ohio
i've definatly got the spacer installed correctly. i've got good spark on both the leading and the trailing. the problem has to be inside of the carb. i'm just wondering if i can pull the top of the carb off and clean the gunk out under the floats. that has to be what i'm sucking up. something just isn't right with the carb. its very frustrating.
Reply
Old Mar 12, 2007 | 07:31 AM
  #7  
DavidMyers53's Avatar
Full Member
Tenured Member 05 Years
 
Joined: May 2006
Posts: 244
Likes: 0
From: Statesville, NC
You have to take some of the emmissions stuff off the carb to get the top off. I tried it while the carb was on the car and finally removed the carb and then removed the top. There's only 4 screws (I think) in the top that have to be removed, and the big bolt that holds the air filter on- it also holds the carb top on.

- David
Reply
Old Mar 12, 2007 | 02:38 PM
  #8  
mazdaverx713b's Avatar
Thread Starter
Have RX-7, will restore
Veteran: Army
Tenured Member: 20 Years
Loved
Community Favorite
iTrader: (91)
 
Joined: Oct 2003
Posts: 22,577
Likes: 1,273
From: Ohio
David, thanks a ton! i'll be removing the carb again today and attempting to get this hesitation problem solved!
Reply
Old Mar 12, 2007 | 04:01 PM
  #9  
StricklyOldskool's Avatar
Senior Member
Tenured Member 05 Years
 
Joined: Aug 2005
Posts: 400
Likes: 0
From: Florida
I would suggest using a in-tank carb cleaner before take that carb off its seat. The carb cleaner will be put in with a full tank of gas and will run through the jetting of the carb along with going in where the floats are. There could be some slight grime that is making it stick, in which case this could losen those particles up and save you hours. If yew do have all the emmissions on... there is like 5 hoses that connect to the blue air breather, a wing nut in the center under the air breathers cap. You then have to remove some other parts around the carb to get a 12m wrench into the 4 bolts that hold the base to the manifold. Once youve removed the carb you will then venture into a headache of dealing with a Niki carb. These are pretty complex little carbz. If you have a buddy with a 12a motor, take his distributor and swap it with your. Be sure you set the timing before dropping the other dizzy in. This will elimenate the ignitors being the issue. best of luck and keep us posted.

cheerz
Reply
Old Mar 12, 2007 | 08:06 PM
  #10  
mazdaverx713b's Avatar
Thread Starter
Have RX-7, will restore
Veteran: Army
Tenured Member: 20 Years
Loved
Community Favorite
iTrader: (91)
 
Joined: Oct 2003
Posts: 22,577
Likes: 1,273
From: Ohio
timing had already been checked. a tank with seafoam had already been run through the tank and all options had been exhausted. i had tried three different carbs, and a slew of new parts. finally today, i took the top of the carb off, replaced the needle and seat, cleaned the float bowls, which were brown and gummed up to quite an extent. i also removed each air bleed aindividually and cleaned each one and blew compressed air through it. once clean, i blew air through the jets and all passages in the carb that could be obstructed. i put gas in the float bowls, installed the gasket, adjusted the floats, and reassembled the clean carb and success. SO FAR the 7 runs beautifully strong and with no hesitation. so far i cant complain. i really think the carb is a fairly simple piece to rebuild and work on. thanks for everyone's input. i'll let you guys know what happens in the future with the running condition of the car!!!
Reply
Old Mar 13, 2007 | 08:45 PM
  #11  
mazdaverx713b's Avatar
Thread Starter
Have RX-7, will restore
Veteran: Army
Tenured Member: 20 Years
Loved
Community Favorite
iTrader: (91)
 
Joined: Oct 2003
Posts: 22,577
Likes: 1,273
From: Ohio
so far so good. i dorv ethe car to the P.D today and all was pretty good. it seems as though when the engine hasn't warmed up fully, i still get a tad bit of hesitation under half throttle and its only for a second then it goes away. once the engine was at normal operating temps today there was no stuttering.
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Andrew7dg
1st Generation Specific (1979-1985)
3
Aug 6, 2017 01:41 PM
eddierotary
Engine Management Forum
16
Oct 4, 2016 08:22 PM
Zinraf
2nd Generation Specific (1986-1992)
3
Oct 1, 2015 01:09 PM
izzolaw
1st Gen General Discussion
2
Sep 27, 2015 08:33 PM
risingsunroof82
1st Generation Specific (1979-1985)
8
Sep 7, 2015 01:11 PM




All times are GMT -5. The time now is 12:27 PM.