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

Expert Advice Needed Quickly! Timing & Fuel Delivery Problems

Thread Tools
 
Search this Thread
 
Old 02-25-03 | 10:02 AM
  #1  
smile444's Avatar
Thread Starter
Full Member

 
Joined: Nov 2002
Posts: 114
Likes: 0
From: Overland Park, KS
Exclamation Expert Advice Needed Quickly! Timing & Fuel Delivery Problems

My 1985 RX-7 GS is experiencing problems with running anywhere close to smooth. I have gone through many important steps to get this car to run well, and have ran into a rather unique problem.

Here is what I have done so far:

1) Complete rebuild of the carb,

2) All-New Exhaust (Armor-coated Monza Pacesetter Header, then straight pipe back to the muffler),

3) Removal of the Catalytic Converters,

4) Complete removal of the Rat's Nest using RX-7 Carl's tutorial,

5) New Bosch Platinum spark plugs,

6) New Fuel Filter,

7) New OEM Fuel Pump.

After all of this, the car still runs like ***, and only gets about 10mpg.

I bought a timing light and found this rather unigue problem when trying to give my REX a tune-up:

-*-* THE YELLOW AND RED MARKS ARE TUNED TO THE REAR SPARK PLUGS!! -*-*

These are the ones that are marked on the dizzy as L2 and T2. It makes absolutely no sense to me as far as anything and everything that I have read in the Mazda Workshop Manual, the Haynes Manual, or on old threads here.

The car is somehow timed completely bass- f*cking- ackwards. No small wonder that it runs like ****.

I have attempted to somehow fix this, and have pulled the dizzy and aligned it with the markings on it, but it makes no difference.

I also called multiple service departments at MAZDA dealerships and they all concurred that the timing should only be set on these cars from the front plugs (Ie. the L1 and T1).

HELP!!

I even believed it to be an ignitor problem on the trailing, but all plugs are firing fine.

I need some sage advice here, this is my daily driver, and I am very very confused about this weird situation. I guess on the good side is that I have eliminated nearly all other possible problems.

Experts and Gurus please weigh in here as soon as possible.

Thank You,

Joe in KC
Old 02-25-03 | 10:23 AM
  #2  
bliffle's Avatar
Rotary Freak
 
Joined: Sep 2002
Posts: 2,815
Likes: 0
From: SF BayArea
I don't know about the RX-7, since I've never had this apart, but on some piston cars the distributor keys into the drive in such a way that it is possible to key it 180 degrees wrong. Seems to me I had this problem on an old Fiat (what else!) and so I had to switch the plug wires to make it run right. Seems to me I made a mental note to switch the dist some day.

B
Old 02-25-03 | 10:40 AM
  #3  
Wankelguy's Avatar
My FSP Fiesta eats Jettas
 
Joined: Aug 2002
Posts: 1,616
Likes: 3
Perhaps the front pulley was disassembled and then reassembled wrong.
Old 02-25-03 | 01:52 PM
  #4  
smile444's Avatar
Thread Starter
Full Member

 
Joined: Nov 2002
Posts: 114
Likes: 0
From: Overland Park, KS
okay, so bliffle, would I just switch the L1 plug wire for the L2, and the T1 for the T2?
Old 02-25-03 | 01:59 PM
  #5  
smile444's Avatar
Thread Starter
Full Member

 
Joined: Nov 2002
Posts: 114
Likes: 0
From: Overland Park, KS
Wankelguy,

Are you thinking that the pulley is somehow attached 180 degrees in the wrong direction? Or could it be?
Old 02-25-03 | 03:46 PM
  #6  
REVHED's Avatar
Hunting Skylines
 
Joined: Apr 2001
Posts: 3,431
Likes: 4
From: Brisbane, Queensland, Australia.
The only possible explanation is that your front pulley is installed 180* off.

This is not the cause of your driveability problems though! If the timing is correct for one rotor it will be correct for the other one as well due to the way the dizzy works.

Last edited by REVHED; 02-25-03 at 04:08 PM.
Old 02-25-03 | 04:43 PM
  #7  
REVHED's Avatar
Hunting Skylines
 
Joined: Apr 2001
Posts: 3,431
Likes: 4
From: Brisbane, Queensland, Australia.
I just realised something... if the pulley is installed 180* off and you proceed to install the dizzy according to the tally marks on the shaft then the timing would be way off. Each rotor would be firing when the other's supposed to. Your car would run like extreme crap if at all.

It makes your head hurt when you start thinking about timing on these things.
Old 02-26-03 | 11:21 AM
  #8  
smile444's Avatar
Thread Starter
Full Member

 
Joined: Nov 2002
Posts: 114
Likes: 0
From: Overland Park, KS
REVHED,

So, um, . . if I switch the T1 & T2, and switch the L1 for the L2, then I would have it at least adjusted correctly?
Old 02-26-03 | 11:32 AM
  #9  
Wankelguy's Avatar
My FSP Fiesta eats Jettas
 
Joined: Aug 2002
Posts: 1,616
Likes: 3
Originally posted by smile444
Wankelguy,

Are you thinking that the pulley is somehow attached 180 degrees in the wrong direction? Or could it be?
Yes, and yes. The pulley is a two-piece affair, and if it is reassembled wrong, the timing could be way off. If my memory serves me, (and it frequently doesn't), the front rotor is at TDC when the key in the E-shaft is at the 9 o'clock position when viewed from the front. I'd get a second opinion on that, though. Good luck. -WG
Old 02-26-03 | 12:59 PM
  #10  
smile444's Avatar
Thread Starter
Full Member

 
Joined: Nov 2002
Posts: 114
Likes: 0
From: Overland Park, KS
WANKELGUY,

Would you agree that my rotors are firing when the other one is supposed to? If so, would a temporary fix be to switch the plug wires?
Old 02-26-03 | 01:40 PM
  #11  
Wankelguy's Avatar
My FSP Fiesta eats Jettas
 
Joined: Aug 2002
Posts: 1,616
Likes: 3
Originally posted by smile444
WANKELGUY,

Would you agree that my rotors are firing when the other one is supposed to? If so, would a temporary fix be to switch the plug wires?
I would hesitate to say yes, without being able to check it out myself. I'd take the fan off and observe the position of the key in the pulley relative to the timing marks to determine if the pulley is in fact wrong. Maybe just the coil wires or trigger wires are switched, it's hard to tell without going through the whole system methodically to eliminate the possible causes. Sorry I can't give you a firm answer, but I don't want to give erroneous advice, however well-meaning. -WG
Old 02-26-03 | 01:50 PM
  #12  
1985 gs's Avatar
Junior Member
 
Joined: Aug 2002
Posts: 21
Likes: 0
From: arizona
I had the same problem on my 85 gs. I couldn't figure out why it still ran like crap. I checked everything ten times over. Timing was all screwed up because i kept adjusting it and had the plug wires mixed up. Just my thought.
Old 02-26-03 | 02:29 PM
  #13  
smile444's Avatar
Thread Starter
Full Member

 
Joined: Nov 2002
Posts: 114
Likes: 0
From: Overland Park, KS
WANKELGUY,

I believe that I will take the fan off and observe the position of the key in the pulley.

By the way, what does the key in the pulley look like?
Old 02-26-03 | 02:37 PM
  #14  
smile444's Avatar
Thread Starter
Full Member

 
Joined: Nov 2002
Posts: 114
Likes: 0
From: Overland Park, KS
Hey 1985 gs:

Did you ever start to get the timing set right once the plug wires were arranged correctly?
Old 02-26-03 | 04:14 PM
  #15  
Wankelguy's Avatar
My FSP Fiesta eats Jettas
 
Joined: Aug 2002
Posts: 1,616
Likes: 3
The keyway is a slot in one side of the hole in the middle of the pulley. There is a steel key in it to index the pulley's position. You'll know it when you see it.
Good luck!
Old 02-26-03 | 04:18 PM
  #16  
smile444's Avatar
Thread Starter
Full Member

 
Joined: Nov 2002
Posts: 114
Likes: 0
From: Overland Park, KS
After pool league tonight, I will see if I can take a peek. I'll let you know.

Man I can't wait to get all this stuff set right.
Old 02-26-03 | 05:05 PM
  #17  
bliffle's Avatar
Rotary Freak
 
Joined: Sep 2002
Posts: 2,815
Likes: 0
From: SF BayArea
I would check it out carefully before switching the plug wires (heck, I just did it on an old Fiat), for fear of blowing apex seals.

But, I think if you examine it carefully and analyze the way the dist works, you'll be able to figure it out.

This is why I'm glad I have two cars: I can look at the one that's working and compare with the faulty one.

B
Old 02-26-03 | 05:32 PM
  #18  
smile444's Avatar
Thread Starter
Full Member

 
Joined: Nov 2002
Posts: 114
Likes: 0
From: Overland Park, KS
Good call. I already did switch them once, and I don't trhink it did any damage to the apex seals. But hey, how would I know??

I'll study the dizzy.

I need a second car.
Old 02-26-03 | 05:56 PM
  #19  
REVHED's Avatar
Hunting Skylines
 
Joined: Apr 2001
Posts: 3,431
Likes: 4
From: Brisbane, Queensland, Australia.
Does the car actually run at the moment?
Old 02-26-03 | 06:23 PM
  #20  
smile444's Avatar
Thread Starter
Full Member

 
Joined: Nov 2002
Posts: 114
Likes: 0
From: Overland Park, KS
yes
Old 02-27-03 | 09:03 AM
  #21  
74RX4's Avatar
Round and Round
iTrader: (10)
 
Joined: Aug 2002
Posts: 1,516
Likes: 3
From: SW Florida
Originally posted by Wankelguy
Yes, and yes. The pulley is a two-piece affair, and if it is reassembled wrong, the timing could be way off. If my memory serves me, (and it frequently doesn't), the front rotor is at TDC when the key in the E-shaft is at the 9 o'clock position when viewed from the front. I'd get a second opinion on that, though. Good luck. -WG
https://www.rx7club.com/forum/showth...&highlight=TDC

This thread describes how to find TDC. The keyway is at 9:00 when the engine is at TDC.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
trickster
2nd Generation Specific (1986-1992)
25
07-01-23 04:40 PM
alphawolff
1st Generation Specific (1979-1985)
17
11-17-15 05:57 PM



Quick Reply: Expert Advice Needed Quickly! Timing & Fuel Delivery Problems



All times are GMT -5. The time now is 08:18 AM.