« Archives in October, 2012

To Do: FWF

There are a LOT of fiddly things firewall-forward. I’m going to attempt to list all the things I can think of that need to be done here, but I’m sure I’ll miss a lot.

1. Secure spark plug wires at cylinders This is actually done. I’m listing it because it might change.

2. Secure probe wires. Not sure how to handle this Done

3. Wire engine sensors Done. Still need to do MAP tube, but that’s not a wire, so nyah.

4. Finish running alt air control cable.

5. Install breather tube

6. Finish securing main wire bundle

7. Seal airbox/filter interface

8. Get proper governor nuts/lock washers

9. Get governor spring.

10. RTV baffles.

Some of this might be post-airport. The pre-airport list is on a corkboard in the living room.

FWF Sensor Wiring DONE!

10 hours.

This is yesterday and today. Yesterday started with an epic shop cleaning. I have those every so often, and it’s helpful, extremely good to have a workbench devoid of clutter, if only for a little while. Stuff got put away, stuff got tossed out, floors got swept and vacuumed.

The fiddling with the FWF stuff has been progressing as well as I can make it, and the wiring has been a bit of a challenge, especially since the K-Type wires on 2 of the sensors were too short to make it all the way to the RDAC engine monitor module. Then there’s the business of where to actually run things so they don’t rub on other bits or get roasted alive by the exhaust pipes. I got the current sensor done, although I suspect I’ll have to flip it over, I got all the temperature sensor wires run, wrapped, and grounded. About the only thing that didn’t happen is the MAP sensor, which needs a 1/8″ to 1/8″ barbed elbow fitting. Searches have turned up no such animal so far. But technically, that’s not wiring, so legally speaking my FWF sensor wiring is done.

Here’s the beginning of the attachment process. The overbraid K-type wires are a ratbastard to work with. They’re a little like shielded cable, but they’ve got an extra woven sheath below the braid that absolutely sucks to try to get off. Maybe there’s a trick to it, but this was by far the worst suckage of this task.

A slightly different angle. On the RDAC (the grey box), the first 4 pairs are exhaust gas temperature thermocouple inputs. Can’t change them, which kind of sucks, because then I wouldn’t have had to extend a couple of TC wires to make them reach the proper input. Oh yeah, splicing TC wire sucks too. The ty-wrapped snarl at the bottom is the FloScan fuel flow sensor wiring. I installed the FloScan months ago, but never got around to properly wiring it until today.

Still a rat’s nest, but there is progress there. This is right after grounding all the things that needed grounding, being the FloScan, the tach sensor, and the RDAC itself. The EGT and CHT probe wires haven’t been cut to length yet, nor have they been secured by Adel clamps to the firewall.

Ahhh, that’s better. Still some wrapping to be done, but all the wiring is secured and attached.

This shows the oil pressure sensor hooked up and run into the bundle. This will benefit from a couple of Adel clamps attaching the main bundle to the engine mount, but we’re in a pretty good place.

Even more fun: Once I got everything wired, I fired up the EFIS and decided to test out whether or not I’d actually inserted the right wires into the right terminals on the RDAC. This was done by means of a heat gun and a blowtorch. The heat gun raised the temperature of the actual cylinder itself so I could check the reading on the EFIS. The blowtorch was for the EGT probes. Suffice it to say that the method of testing was a great success: I found I had miswired the 1 and 3 cylinders for EGT, and the 2 and 4 cylinders for CHT. It is now all fixed.

Some sensor wiring.

1.5 hours

Tonight I was able to do a little more work on the engine sensor wiring. Mostly it was about figuring out routing and wrapping hi-temp spiral wrap around probe wires, which is such a chore. Not as bad as Adel clamps though. I have to figure out the technique for those, because they’re killing my fingers. Anyway, the major visual effect achieved tonight is now the plug wires don’t hang out the bottom like sword-slashed entrails. I also got started on wrapping/routing the probe wires, but the wrap will have to come off because I forgot about the MGL current sensor that’s supposed to go on the alternator wire. Grmp. I also had to splice one of the EGT wires, because it was too short to make it all the way to the RDAC. I’m a little concerned about that. Oh, and I have no idea what wire goes to which cylinder. Yep. Awesome, that’s me.

I’m sick of this airplane. My wife is REALLY sick of this airplane. I need to get it done, and soon.