Firing order confusion

code7rpd · 10-17-2005, 10:00 PM

Where do I begin....I bought another '81 SC. I got a good deal on it knowing that it would need an engine rebuild. The motor had a knock and according to the PO, motormiester did the prior rebuild, so, I knew it would have to be done right.

Today I dropped the motor and began pulling it apart. I noticed that every o ring and seal had gobs of silicone around them - took forever to get things apart - thanks MM. I get around to pulling the distrinutor and mark all of my plug wires from 1 to 6. After pulling the dizzy I check the wires in relationship to the dizzy cap and find that wires are positioned so that the rotor fires at 1-4-3-5-2-6 (with the rotor going counterclockwise). The motor was running fine but was knocking. Is it possible for the engine to run with this firing order? The correct firing order is 1-6-2-4-3-5 correct?

2.7RACER · 10-17-2005, 10:37 PM

I could be wrong, but I suspect you may be turned around just a little. The motor would not run with 1-4-3-5-2-6.
However if you look at going the other way around the dist cap you get 1-6-2-5-3-4, which just has 4 and 5 switched. Easy to do.
1-6-2-4-3-5 is correct.
Sorry to hear about MM, you have my condolences.

code7rpd · 10-17-2005, 11:46 PM

That makes sense. I'll double check my cap to make sure I marked it right. If the rotor on the SC's travels counter clockwise then 6 would be to the right of 1 correct?

code7rpd · 10-18-2005, 12:07 AM

I double checked it and if the rotor moves counter clockwise then my firing order is definately 1-4-3-5-2-6. If the rotor moves clockwise then it is set for 1-6-2-5-3-4.

Wil Ferch · 10-18-2005, 09:12 AM

SC's switched dizzy rotation one year...just to drive us mad !

Wil

code7rpd · 10-18-2005, 11:41 AM

So when I put it back together I want to make sure that 6 is counter clockwise of 1 and 2 is counter clockwise to 6 etc?

Bill Verburg · Bill Verburg's Garage

All 911/964 and 993 distributors rotate clockwise, EXCEPT '78 to '83 SC

firing order for the ccw rotating SC dist. is 1-6-2-4-3-5

of course all the others have the same firing order just w/ a dist that rotates cw

In all single plug engines #1 is closest to the fan housing strap

code7rpd · 10-18-2005, 03:53 PM

Got it. Thanks.

tsuter · 10-18-2005, 05:19 PM

Don't go by your Bentley 911SC service manual . Its wrong. Muhahahaha!

code7rpd · 10-18-2005, 07:11 PM

Tsuter, what do you mean? Where is it wrong?

tsuter · 10-18-2005, 07:22 PM

Quote:

Originally posted by code7rpd
Tsuter, what do you mean? Where is it wrong?

280 Ignition System - Firing order: "Note: The ignition rotor turns in a clockwise direction".

This would be incorrect. The rotor turns counter clockwise

Bentley Publishing Stock No. P983 editorial closing 10/00

Hook em up by the manual ... you get a big bang!!

code7rpd · 10-18-2005, 09:42 PM

I just made the correction. Here are a few pics of the engine drop and my make shift engine clean room (need to keep the dog hair out)