993 backfire/intake separation -- causes & questions

[NOLAsc]

Thanks. I pulled the secondary rotor and the belt's definitely gone. Pictures later.

Shawn

[bazar01]

Originally Posted by NOLAsc

Thanks. I pulled the secondary rotor and the belt's definitely gone. Pictures later.

Shawn

wish I have a good neighbor here who can do my dizzy belt too...

[NOLAsc]

Originally Posted by bazar01

wish I have a good neighbor here who can do my dizzy belt too...

Funny.

I don't think I'll be the one to rebuild the neighbor's distributor. There's some labor in that. And the need for a better timing light.

I took my '82 sc distributor apart last year. I had a machine shop cut bushings to fit. (It's documented somewhere on the 911 tech forum.)

I was just happy to get the neighbor's car to run on the primary dizzy today (taped up the leads to the secondary coil and wedged them between the plug wires on the secondary cap). The neighbor seems to really appreciate Porsches and I hated to see her car just sitting abandoned. I pulled the DME relay to crank it a few times, hooked up a charged battery, opened the unlocked door and promptly set off the alarm. Fun stuff.

Shawn

[bazar01]

Just kidding. I rebuilt mine at 84k miles and it was about to break.

The right way to disable the secondary is to disconnect the final stage ignition control unit just below the coil. This way, the coil will not generate the high voltage spark.

[Traveller]

Originally Posted by NOLAsc

I pulled the secondary rotor and the belt's definitely gone. Pictures later.

In that case, since you cannot spin the secondary distributor rotor, the bearings must be seized. Let us know.

I know you said the rotor rotates a bit. That is because it is rotating about the shaft.

[Traveller]

Originally Posted by NOLAsc

I don't think I'll be the one to rebuild the neighbor's distributor. There's some labor in that. And the need for a better timing light.

You do not need a timing light.

[NOLAsc]

Originally Posted by bazar01

Just kidding. I rebuilt mine at 84k miles and it was about to break.

The right way to disable the secondary is to disconnect the final stage ignition control unit just below the coil. This way, the coil will not generate the high voltage spark.

I unbolted the two leads from the top of the secondary coil (under the rubber cover) and wrapped them up in electrical tape. I don't recall seeing anything below the coil.

[NOLAsc]

Originally Posted by Traveller

You do not need a timing light.

Don't you still have to re-set the timing after you put the thing back in?

I have a variable timing light (cheap harbor freight one) that I don't really trust.

[Traveller]

Originally Posted by NOLAsc

Don't you still have to re-set the timing after you put the thing back in?

Nope!

The distributor installs in one position only. Gone are the days where you'd rotate the distributor and then tighten a hold-down.

[NOLAsc]

Originally Posted by Traveller

Nope!

The distributor installs in one position only. Gone are the days where you'd rotate the distributor and then tighten a hold-down.

Well... that's cool. Maybe I should just trade engines with her.

[NOLAsc]

Meant to post this last night. Apparently there was water in the secondary. (This car leaks some. The tool kit was sitting in a puddle of water up front, some tools rusted badly.)

Anyway, this pic is not for the faint-hearted...


Ain't pretty.


Arrows point to the belt.







I cleaned it out as well as I could. Oiled it down. Oiled under the felt of both dizzies.

[Traveller]

Originally Posted by NOLAsc

Apparently there was water in the secondary.

OMG, looks like it suffered from Katrina.

Now that the belt is confirmed broken, put the rotor back on. It should spin freely with just your finger spinning it around. If not, break out the wallet. At this point, I'd check eBay for a used distributor.

[Augurean]

Originally Posted by Traveller

The distributor installs in one position only. Gone are the days where you'd rotate the distributor and then tighten a hold-down.

Yep, distributor pretty much only picks which cylinder, the computer does the timing.

Also, because of the shape of the gear, be careful when re-inserting the distributor, as the rotors will twist a bit clockwise when the gear mesh.

After seeing that picture, I wouldn't even try fixing the thing, just get a used one on eBay or from the used parts forum.

[NOLAsc]

Yep. If it were my car, I'd drill the pin and pull it apart just to see. Twenty bucks vs nearly a thousand or so. The thousand could wait another day.

But, or course, it's not my car.

Shawn