Skytec starter installation in Continental C 85 C75 O200

On factory pull-start engines (C85-12 thru O-300-C), certification eligibility is by modification per:

1)STC SE10076SC(engine modification),
2) STC SA10077SC (airframe modification to replace pull-start mechanism with push-to-start button)

Download a Letter of Authorization to use the STC's.

Ercoupe_Old_Shaft.JPG Ercoupe_Cutting_Half.JPG

Converting an old pull-type starter to the KCST2 is very easy



STEP 1:  Order a KCST2   (not a C12ST2 or a C12ST2/S - just order a KCST2)


STEP 2:  Prepare for installation:  cut off the pinion shaft


Step 1 - Out With Old

Gather Tools

(NOT these tools)

OK - These tools are more like what you will need

Remove old starter -

Weigh it (ours was 16 lbs)

Here's what you'll see - 

A shaft (your victim)

Step 2 - Prepare to Cut

Prepare the area

Clean out all oil around shaft

Make a cardboard cutting shield using the enclosed template

Pack some clay

Enclose all gaps

Get ready to cut

with 1-1/4" fibrous Dremel bit

Step 3 - Cut The Shaft FLUSH

Problem: Our Dremel tool's neck interfered with the shaft...

...we couldn't get a square cut so we cut shaft twice...

...First cut only half of shaft

Then go back and get all of it

This will make clearance

for neck of Dremel tool

Step 4 - Clean & Install

Your shaft should be cut FLUSH - that's within 1/16" of the case

Flush area with long stream of clean fluid (we used WD-40)

Remove shield & clay

Wipe clean

Mount new starter

Torque per instructions


Step 5 - Wire & Sign

Follow instructions in box (KCST2) to wire the new starter

You'll use these terminals

to wire power & new switch

Send in your 337's

Have A&P sign logbooks

Not nearly as fun as flying the thing when you're done, though.



STEP 3 :

Familiarize yourself with the STC # SE10076SC and other paperwork.



Installation details are covered thoroughly by the installation paperwork included with the KCST2 starter.


However, two notes that are easily overlooked:


1)  CUT FLUSH - You need to cut the OE starter pinion shaft off FLUSH.  How flush?  FLUSH.  Can you leave any of it hanging out?  Hmmm...maybe up to a sixteenth of an inch at MOST (0.0625").  Better yet, cut it FLUSH without damaging or marking up the crankcase halves.  


2) BOLTS - You need to reuse the OE Continental bolts to secure the top of the starter.  Our STC was predicated on a default scenario wherein the customer is replacing an OE pull-type starter.  If your engine did not have an OE pull-type starter installed (you have been hand-propping), you will need to find/buy/borrow or steal the OE pull-type starter mounting bolts.  They are odd ducks.  5/16"-18 thread (coarse) and a freakishly uncommon length with a drilled head.  The Continental P/N for these bolts is 538999 which our customers believe is an MS20074-5-33 bolt.

One user report: your experience may vary

I finished installing the Sky-Tec starter yesterday following their instruction sheet which generally speaking is adequate. However I can add some worthwhile items. The cardstock template is a good start but I made a second one after fitting the first one and finding that it can be tailored to fit a bit closer into the crankcase cavity.
Be very generous with the use of the modeling clay. I started with a 1 lb. brick and used 2/3rd's of it. The more you use to block off the area, the less cleanup of grinding dust will be required. I used a Dremel flexible shaft machine which has a small diameter handpiece so getting into the space was easy. I used a reinforced cut-off wheel. I cut very close to the face of shaft large diameter. Do not attempt to cut into the shaft from underneath it as you will cut thru the template and into gear teeth. All cutting should be done from above. I cut thru 95% of the diameter and simply broke off the remainder.

Upon fitting the starter I tried to determine how close the starter came to the remaining shaft. By putting a small piece of modeling clay on the stub shaft I determined that there is about 3/8" at least clearance. What this tells me is that trying to keep the shaft stub very short is not critical. A 1/4" stub would suffice and make it much easier to accommodate the cut-off wheel.

The Sky-Tec really whirls the engine !!

Cheers John