964 valveadj/tune-up questions

spain · 05-02-2008, 12:17 PM

Greetings! Pretty new 911 owner here. I have a 1989 C4 with no good service records (I know, I know). Anyway, it has 97K miles on it and I'm adjusting the valves and giving a tuneup. I have a few questions:

1. While removing one of the ignition leads on the bottom distributer cap the connection felt loose ond the wire. The connection inside the boot was broken. The wire looks good. The stab on the distributer cap was whitened while all the other stabs are good and shiny.
-I ordered a new ignition wire connector; do I need to attach it back on with a regular wire crimper or is there some special Porsche tool required?

2. All the distributer contacts and the distributer rotor contacts were blackened and pitted all to hell.
-Does this mean there is a timing problem or just distributer caps that are long overdue for replacement? i have new rotors and caps to replace.
-Does this mean I was not getting all the power I could out of the engine? Is there any reason to be concerned with all those cylinders not getting full spark?

kang · 05-02-2008, 12:47 PM

I don’t think it’s possible to tell if there is a timing problem or the caps & rotors are just overdue. Certainly replace them, and also consider replacing all the plug wires. Sure, you can fix the one that fell apart, but who knows what other problems might exist in the other wires.

How do the plugs look?

spain · 05-02-2008, 02:35 PM

thanks. kang.

I have not pulled the plugs yet. I'll let you know when I do. Since my valves are loose (audible tapping) and the dist cap looks like it does I'm going to assume it is just plain overdue for a tune-up and not the timing problem.

Spain

Don Plumley · Don Plumley's Garage

I doubt it is a timing problem, like you said, just overdue for cap/rotor.

Does the distributor have the vent kit (a clear hose from the heater blower to the side of the disty)? Might be worth replacing the belt - a tough DIY.

Plug wires have a special end crimped on that screws into the connectors. There are special tools for this, but at 97K miles I think you should bite the bullet and replace the wires. Some have found wire only sets and replace the connectors from the car to save money.

Don

spain · 05-02-2008, 06:02 PM

Thanks! I do have the vent mod. My lugs look okay for normal wear. The lower ones looked worse. There was some buildup and blackening; still could see normal burning. these were the tri-tip Bera's. showed the pugs to a mechanic friend; he said looks like cheap gas and lugging the engine (I don't lug that engine- PO must have). He also said dist caps showed that the contacts were worn back and you can see were the arc was traveling well past the contacts. BTW a valve adjust is somewhat a PITA! I'm having fun but man is t time-consuming!

-Is it just better to back the screw off, insert the feeler guage, then screw down for adjustment?

spain · 05-02-2008, 06:03 PM

sorry that "plugs" not "lugs"!!!!

kang · 05-05-2008, 09:36 AM

Sounds like you’re taking care of some neglected items. These cars are pretty strong, and hopefully once you’ve gotten past all this stuff, you’ll have yourself a sweet ride.

Might I also recommend you flush the brake and clutch fluid? This is pretty important to do every couple years, and given what I’ve heard of this car, I bet it’s been neglected as well. Of course, this might already be on your list….