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PatrickM · PatrickM's Garage

I had my distributor out of the engine. I put it back in with the rotor pointing toward the notch(#1 plug wire)with the
crank pully at TDC. If I was off by one tooth, would the car not start? The car cranks and cranks and cranks and just won't fire. Smells like gas too, so I havta guess it's not a fuel supply problem.

Thanks....

Jim Sims · 09:57 AM

If you turned the engine over with the distributor out you might not be at TDC for cylinder no. 1. If this is the case, put engine back on TDC turning CW. Remove distributor; turn engine (clockwise) exactly 1 turn to TDC again. Reinstall distributor. Do you have the spark wires installed correctly and all the ignition wiring installed? Jim

PatrickM · PatrickM's Garage

The distributor is in correct. The #1 intake valve opens and closes just before the rotor gets to the notch on the dizzy housing and the crank pully gets to the Z1 mark. The plug wires appear to all be correct.....162435 right?

The wires are new Magnacore, new plugs, new cap, new rotor.

Thanks.

-Patrick

Jim Sims · 05-23-2003, 10:09 AM

year and model?

911pcars · 05-23-2003, 10:38 AM

"The #1 intake valve opens and closes just before the rotor gets to the notch on the dizzy housing and the crank pully gets to the Z1 mark."

How would you know this without removing the upper and lower valve covers? I'm not saying you didn't remove them to verify, but this is not normally done to just R&R the distributor or maybe you were adjusting the valves.

The crank rotates twice (720 deg.) during a 4-stroke cycle, thus each piston is at TDC twice; once at TDC, end of exhaust/beginning of intake (i.e. TDC overlap) and once at TDC end of compression/ready to fire.

If you disturbed the engine with the distributor removed you may have reinstalled the distributor with the engine NOT at TDC end of compression, but some other position in which case the engine will not start. I assume your engine ran fine before the R&R? Follow Jim's suggestion, then get back with us. If you need to find TDC end of compression, let us know.

Sherwood Lee
http://members.rennlist.org/911pcars

PatrickM · PatrickM's Garage

Thanks guys, I appreciate all of the help...
1977 911 2.7 CIS

I removed the distributor(cleaning around it) and rotated the engine(oops).
I then removed all of the valve covers to prepare to adjust the valves. I then realized my blunder. I then rotated the engine until the #1 intake opened and closed and then the crank pully came up to Z1. I replaced the distributor and rechecked this with a screwdriver in the spark plug hole. I turned the engine(clockwise always...of course) and saw the rotor go around once to the two revs of the crank. The screwdriver gets pushed out when the #1 piston gets to TDC twice in the process. I checked and rechecked this.
"The crank rotates twice (720 deg.) during a 4-stroke cycle, thus each piston is at TDC twice; once at TDC, end of exhaust/beginning of intake (i.e. TDC overlap) and once at TDC end of compression/ready to fire."

So, of the two TDC's that you mention....which is the TDC that the rotor should be aligned with the mark on the distributor housing?
The #1 intake opens and closes when the rotor is about 180 degrees from the notch on the housing and then the rotor continues around to the notch and the crank gets to Z1. Is this the TDC that I need??

Jim Sims · 05-23-2003, 12:48 PM

Early distributors (through 1977) turn clockwise so ensure your plug wires are wired in a clockwise firing order. Do you still have ignition points? If so, are they set correctly? Is the new rotor seated properly on the distributor shaft? Pull a plug wire, put an old plug in it and lay it against the engine and see if you get a spark (keep clear of the high voltage). Jim

911pcars · 05-23-2003, 01:02 PM

Patrick,
Sounds like you are doing it correctly:

1. #1 piston is at TDC ready to fire (both valves closed), TDC marks on pulley and crankcase are aligned.
2. Insert the distributor so the rotor points to the notch on the dist. housing.
3. Start engine and set basic ignition timing. BTW, you can also do this with the engine OFF/Ignition ON as well. Let me know if you need this info.

Sherwood

PatrickM · PatrickM's Garage

Once again guys, thanks so much!!!

Jim, yup, clockwise.....162435.
Yup, still have the points, which should still be set correctly, I haven't touched them. I'll pull the cap and rotor again and see if all is fine. I still wonder if the distributor could be off by one gear tooth...would that keep the engine from firing? I thought that it would just run rough if that happened.
I'll try that with an old spark plug...where on the engine should I lay it, I don't wanna burn/torch/destroy anything....yet.

911pcars · 05-23-2003, 03:02 PM

If you use an extra spark plug to test for spark, the metal threaded area/side electrode must touch against the engine (or connect a test lead between the spark plug side electrode and engine ground.

You can also remove the coil wire off of the dist. cap and position it close to ground so a spark can jump as you crank the engine.

All this shows is if you have spark. You still have to determine if the spark is happening at the right time.

Sherwood

Jim Sims · 05-23-2003, 03:13 PM

Put plug down against any bare, unpainted engine part (chain cover, unpainted valve cover, etc. Ensure it and the plug wire do not get tangled in a belt. Check your ignition timing and dwell if you have a timing light and dwell meter. Jim

PatrickM · PatrickM's Garage

Hey guys, I've checked everything that you've mentioned and it still doesn't seem to be getting any spark. Could it be the coil? Also, I had the alternator out of the car but I'm positive that I wired it correctly. I wouldn't think that this would affect the spark from the distributor to the spark plugs anyway....
UGH.

Jim Sims · 08:32 PM

For 1977: a black and purple wire should lead from terminal 1 (points) on the distributor (terminal is on the side of distributor) to a 2 wire connector below the electrical chassis under the plastic cover on the driver's side of the engine compartment. A white wire should also connect to (branch off) the black and purple wire at this two wire connector. This white wire then connects to terminal C on the CDI box mounted just forward of the electrical chassis. A red wire runs from terminal B of the CDI box to the 2 wire connector (to the second terminal of this connector) below the electrical chassis. Two grey wires should run from terminal D of the CDI box to ground. A wire (It may be brown but I'm not sure of the color) should run from terminal A of the CDI box to terminal A of the coil. A brown wire should run from terminal B of the coil to ground. When you turn the ignition key to the on position (not start position) do you hear the CDI box "whine"? Are you sure the points are opening? Cheers, Jim

PatrickM · PatrickM's Garage

Jim, you are the MAN!!! Porsche Guru Jim as he shall be called.
Thank you so much!! I had my wiring slightly wrong and
had no idea. The existing wire to the distributor was a wire inside of a wire....weird, yeah. The outer wire was the ground
from the CD box and the inner was the wire that goes to the distributor. I didn't realize this when I put a new terminal on it a few weeks back....I was running the neg and the pos to the terminal on the side of the distributor and it just wasn't working. Your wiring diagram explained it so I knew what to look for.
WaaaaaaaHHHHOOOOOOOOOOOoooooooooooo!
Thanks again!

-Patrick