JPI install details (long)

Long long story for the archives cut short: 60 hours logged and signed off
in my AMT log but my JPI EDM 760 Twin plus Oil temp is installed.
Everything works as advertised. For those who may contemplate this install,
read the Install manual AND the website FAQs several times. JPI's
documentation is far from complete and concise and you'll pick up required
tips and procedures from several of their documents. Don't even get me
started on their operators manual vs. recent firmware revisions!

Here are the put yourself to sleep details:

A couple months ago I had one of those airplane upgrade dreams that all
owners eventually have. New this, new that, wouldn't this be cool, if I
only had this... you know the dream where the sheep that you're counting all
have $$$ painted on their sides, your bank account is unlimited, and all
your wife ever says is "Sure honey, that would be nice."

Anyway, my dream started off with a JPI EDM 760 Twin engine analyzer that
featured indicators for both engines in one 3 1/8" display. Those 14 orange
bars (I dreamt that I had the optional Oil Temp probes) flashed and
flickered as the $heep merrily hopped along through their pasture of lush
green grass (obviously another money metaphor). It continued on with a
Shadin dual fuel flow indicator that is STC'd to eliminated our old
inaccurate Piper fuel flow pressure gauge and interfaced with our King KLN94
GPS. Ahhhh life is good and all these new blinking lights and numbers make
me feel like a real pilot..... zzzzzz....

As with most things in my flying life, I began to justify this project first
in one way and then another. "I'd like to get it installed before we
overhaul our left engine..... I should do it now while it's still warm out
and I won't have to heat the hanger to do it this winter.... I can do it
one piece at a time and it won't cost so much.... I can do it myself under
the supervision of my A&P and save install $... With over 75% of the value
of our airplane tied up in engines, I really ought to know what they are
doing." I'm sure that most of you have used these same arguments, if not
with your wives, with yourself, so I'm betting you know what I'm talking
about.

The next day I started shopping for price quotes and the die was cast, the
Aztec was getting an engine monitor.

I begin thinking that I could buy a used indicator on ebay, have the
firmware updated, and buy new probes and a wiring harness. The STC is
available from JPI and this idea "almost" pencils out, however JPI decided
to continue their Oshkosh special and offered a $300 rebate plus 2 free
option probes. This threw my favor towards a completely new system,
including the warranty which I wouldn't have gotten by going piece-meal.

After several phone calls and endless emails, Gulf Coast Avionics had the
best deal and the most informative salesman, so he got my business. I
decided to add 5 feet to the normal 20 foot wiring harnesses just to be sure
I'd have enough wire, and as it turns out, I'm thankful that I did, this
left me plenty of excess to create service loops and I ended up using 3 of
the 5 extra feet reaching my #1 and #2 cylinders.

While I waited for the unit to be shipped, I spent plenty of time perusing
part 43 and JPI's manual for the proper methods and techniques of running
and securing the wiring harnesses. I eventually ended up ordering a small
fortune worth of heat resistant wedge type adel clamps, bolts, and steel
stop nuts. Inquiries to this and other internet groups several A&P's that
I've come to trust and respect suggested that using adel clamps and doing it
right would be worth the extra effort and expense down the road, ie: plastic
zip ties would eventually get brittle and break. But what route to take
from the firewalls to the cylinders?

Commercial break, flash back, rewind, grab another beer.... Does this ever
happen to you? Just when you've spent some serious money on a project that
might not be necessary, but is definitely an improvement, something comes
along that you just CAN'T pass up. Only days after I shelled out for the
complete JPI EDM 760, the eBay gods send me a "watched list" notification
for a complete leather interior, only 2 years old including the complete
seats for a 1966 Aztec.... and it's maroon. It would match perfectly!
Uggg!!! I've got to bid on it! I price it using Airtex's catalog and
figure out that it would cost over $10k, new. We bid $3k, win the auction,
at the reserve price, fly to Ft Lauderdale (17hrs on the hobbs in under 26
clock hours) and bring home the interior. JPI project gets put on hold,
interior gets installed leaving the forward pilot and co pilot side panels
open to run the JPI wiring harnesses through the wings and into the cabin.

Back to your regularly scheduled program:

Our IO540's have their alternator cable routed one side and the starter
cable routed on the other, both are tucked inside and above the intake
tubes. However, the JPI instructions clearly state NOT to tie the probe
leads or the wiring harness to these cables for fear of getting improper
readings. This lead to a suggestion by my local A&P, secure the alternator
and battery cables to the sump bolts using adel clamps and then using double
adel clamps secure the JPI wire bundle to the battery and alternator cable.
Easier said than done. My thumb and finger tips can attest to just how
difficult it is to get your hands between the intake and exhaust tubes then
secure an uncooperative adel clamp to a sump bolt! This was definitely NOT
part of my dream, however, once completed, it made for a very neat, secure,
and unobstructed install.

The CHT probes and the EGT probes installed without a hitch. By the time I
was finished, my fingers had become quite nimble installing the 52 tiny
screws, 52 lock washers, 52 nuts, several feet of shrink tube, anti-chafe
cover, triple tie wraps and triple tying with waxed lacing.

(insert thread about removing the oil galley plugs here, heat and patience
is the key)

After several checkups and inspections by my A&P, I was ready to install the
indicator and connect the wiring harnesses. I wanted to install the JPI in
the upper left hole on the copilot's side. This required pulling a 2nd
altimeter, moving it into the lower right hand side because the panel had a
hole located perfectly for the adjustment knob. But, this is where my
factory fuel flow lived so that would have to move upward to the upper right
hole, which I made available by removing my right tach and installing a dual
tach.

The system requires a ground wire run to one of the engines, which JPI does
not supply wire for, but the electrical connections are fairly simple. The
ground wire and the power wire are pigtailed out of the power/option
connection, so you just splice in a 2 amp circuit breaker or inline fuse to
the power wire and splice into the ground wire that you ran to the engine.
The oil temp, outside air temp, and TIT probes also get connected in this
same connector. (If you choose the CHT bayonet adapter probe to work in
conjunction with your factory CHT's you also have to ground those individual
probes to the engines)

With everything moved, installed, secured, and approved it was time to crank
'er up and see if all the blinking lights actually blinked. Ahhhh!!!
Perrrrfect! I'm a happy camper and overdue for a nap....hmm... what's that?
A $heep with $hadin dyed in it's wool??!! Lord have Mercy.

Jim