Fuel pump wiring...
 

I decided to solder the wires, heat-shrink, etc.

http://forums.pelicanparts.com/uploa...1365355301.jpg


Now I'm confusing myself a bit. Since I'm running my Carrera fuel pump in back (in the stock MFI location), I have just run the rd/gr wire directly back to the pump, with the in-line fuse. That's all I need correct? The rd/gr is the hot wire when the ignition is on and the DME determines that power should be sent to the pump, right? For some reason, I started second geussing myself and thinking I had to tap into a hot power source to power the pump.

Roger

That is fine, fuse should be 25A. Rd/Gr is powered by the DME relay. The DME turns the pump on when it sees engine rotation and shuts it off when the engine stops.

Coil and anti-theft...
 

OK, made some progress today. Got the fuel pump in and all the related lines, etc. Figured out everything for my heater fan et al.

However, one thing that I would be interested in feedback on is my coil and anti-theft wiring. I decided to use my CDI power wire from the old harness (pin 13 in the chassis plug) to power the coil and the anti-theft. I pulled the 13 pin from the plug and spliced the black coil wire with it. Then I took the anti-theft wire and added a ringlet on the end so that I could attach it to the power terminal on the coil, thus both will receive power with the ignition on. This seems reasonable to me, since I don't have a CDI box anymore, and the coil and the anti-theft both need power with the ignition on. Make sense?

Roger

Makes sense, should work out.

More wiring questions...
 

Do you think I need to have a fuse in the +12v coil wire? I assume if I don't use a fuse, I run the risk of damaging the coil in the event of a surge? Anything else?

On a different note, the yellow wire that needs to be connected to a "start" power source. I assume I could just tap into the starter solenoid wire? Does this need to be fused? I'm trying to avoid messing with the ignition switch and related wiring, if at all possible.

Thanks.
Roger

While they are not perfect, Porsche has never used a fuse to the coil, and I have never heard of anyone else doing it, so I would skip it.
You can tap into the yellow starter wire anywhere that is convenient.

More wires...
 

Ed (or anyone else),

Any idea what these wires are for? Two heavy gauge yellow and two red with female pin receivers, clustered together toward the back of he engine bay. Could this be related to AC components? I haven't seen any reference to these in the other conversion/transplant posts.

Thanks.
Roger

http://forums.pelicanparts.com/uploa...1365681765.jpg

Hard to say since I sold my engine and harness, but could be part of the connector to the engine fuel injector connector. Mine was by the shock tower. Nothing to do with A/C, Grn and Grn/Y to the DME are the only A/C connections in that harness.
Here is a quick sketch I did when I got my setup. Mine did not have the O2 sensor wiring.
http://forums.pelicanparts.com/uploa...1365704356.jpg

Thanks Ed. The one thing that seems strange though, is that this is a group of only 4 wires. It would seem like if it were for the injectors, there would be 6. Also, the gauge seems pretty heavy (maybe 14?). This would seem to imply some sort of high current application. I didn't think the injectors drew that much current.

I'll look around the engine itself and see what I can find. I have the Bentley manual, so I should be able to find it in there (just takes forever).

Roger

Looks like the chassis side of the fuel injector connector. It is missing it's brown case that makes it a connector.

The 3.2 injectors are batch fired, the fuel injector plug is indeed 4 heavy gauge wires.

This is helpful. Apparently when they removed the wiring harness they lost/damaged the housing for these four. That may make it a little more difficult to match up with the male plug. I suppose these must correspond to pins on the DME end, so if all else fails, I can identify them by running current through them and finding the corresponding pin at the DME harness end.

Roger

Roger, I took a couple pics of a '86 3.2 harness i have.

This is of the male and female fuel injection plugs.

http://i1178.photobucket.com/albums/...ps214e065a.jpg

This is the back of the chassis side (female) plug with the cover removed.

http://i1178.photobucket.com/albums/...psaf380445.jpg

I looked at the wiring diagrams, and the colors seem to match the 84-85 harness. In '86 the Yellow was changed to Gray.
http://forums.pelicanparts.com/uploa...1365722994.jpg

Got it! Thank you. of course if I had taken a second to look at the engine before I posted, I would have seen the plug right on top. I do appreciate the help.

Roger

Starter terminal cover/boot...
 

I'm in the processing of bolting the engine and tranny into the car and I realize I don't have the little rubber boot that goes over the positive terminal on the starter. No one carries a generic boot and the Porsche dealer didn't have one in stock. I want to get this bolted in this weekend, so I picked up a cover at a marine store. It covers the terminal, but it certainly isn't a "water tight" fit. Does it have to be? I don't really recall how my old boot fit (it's an aftermarket high torque starter), but I doubt it was water tight.

Roger

Sounds fine, its really there to keep the 12v positive protected against accidental grounding.

OK, thanks. I didn't think it had to be water tight.

Now, I just want to vent a bit...

I'm trying the bolt up the motor and it's getting hung up about 1/2" or 3/4" short. Guess what? The damn high torque starter is hitting the cross member. I clocked it around so the heater hose hose would clear, now it's hitting!!!

I know I'm not the first with this happening, and its not the end of the world, just frustrating. Gotta take it back out, reclock, reinstall. All this little s##t just eats up time.

I'm going to bed!

Roger

Engine crossbar has threads!
 

Learned something new today. Apparently at some point, Porsche went to a engine crossbar that has integral threads in it, versus having to put the nuts on the bottom. I got the engine raised up into the engine bay and I couldn't figure out why the mounting bolts didn't just slide through the bolt tubes on the end of the crossbar. Looked in the Bentley manual and saw they don't show nuts on the bottom.

Interesting though, there appears to be only one crossbar available now, shown for '65-'89. I assume this superseded the earlier one with nuts.

Roger

Oil pressure sender adapter...
 

It occurred to me that I still have to change out my 3.2 pressure sender to match the early gauge. Based on what I have read, it would appear that I need a M18 to M10 adapter/reducer to allow me to screw the early sender in place of the 3.2 sender. Pelican doesn't show these. Anyone have any suggestions as to where I could find one of these?

Roger

Pressure sender...
 

I guess it will be unlikely that I find the necessary M18 to M10 reducer to allow installation of the old sender in place of the 3.2 sender. This leaves only the option of placing the '72 sender on top of the engine in place of the pressure idiot light switch. This would've been a hell of lot easier to do BEFORE I installed the engine. Oh well, live and learn. If I can't get a M18 plug at the local hardware store, I know BAT sells them.

Sending units - Our host offers two sending units; OEM for $134, and Uro for $25. Can anyone give me a practical reason why I should spend $109 more on the OEM part?

Roger