Sam,
It's hard to guess what you might have on your boat, but let me take a stab. If you have a below-deck autopilot, and it has a Raymarine control head, the odds are pretty good that it's a Raymarine down below, too. You probably have either the 5000 or 6000, and the manuals for either of them can be downloaded from Raymarine:
[URL]http://www.raymarine.eu/view/?id=1836&collectionid=10&col=1838[/URL]
Getting a small person to confirm serial numbers and/or model numbers might be a good idea.

Sam, what I've found about those manuals is the there may be only a handful of pages you actually will really need to print out, then you can leave them on the boat. Most of the rest of the manuals are fluff or things you need for startup only. Saves a lot of trees. And if you take your laptop to the boat, you have it all. I do, but only sometimes. I do, however, have a book of "important" stuff in a binder on the boat all the time.

I really haven't spent much time crawling around an a C36. Found one picture on YW showing the aft cabin. Is it possible to access the autopilot through the access door? Or if that is not standard, by adding one.

I can barely get one arm through that hatch, let alone do any sort of work, since it almost always would require 2 hands. I've been curious just how structural that bulkhead is, and if the hatch could be enlarged; or if additional access hatches could be made. But I'd want to be sure it wouldn't compromise the structure.

I've never been in a Mk1, but isn't the aft bulkhead removable? I realize that the stern section of the Mk II is different, and may require the additional support.

Gary,
In this case, the MkI is far superior to the MkII, IMHO. The lazarette (which is across the entire transom) has a removable floor. Once you remove it, you have wonderful access to the steering quadrant, below deck autopilot, etc. Trying to do anything from the aft cabin is a royal PITA.

Also on the MKl you can remove the whole bulkhead it is a 1/2 dozen screws or so. By doing that you will have all the room you need to get at everything in the aft end. I have removed my rudder twice and access to the quadrant is great. I have the walk thru stern just before the complete change to the MKll.
This bulkhead seems to be just a partition vs. being anything structual.

There are three tricks to gaining access to the aft lazarette area via the aft cabin access panel. I have a photo of me spending long intervals in that access port, half in and half out of it...see my article on my below-deck autopilot installation in the C36IA Technical - Upgrades library.

My tricks are these:
1. I am only 185 lbs, so there is not too much girth to cram in there.
2. I removed the wooden frame around the access port.
3. I got a short piece of 1" dia PVC tubing at Home Depot, split it lengthwise, and used a heat gun on it to soften it enough to open the tubing up for a slot that would allow it to fit over the sharp bottom edge of the access port. This makes it a lot more comfortable to spend 'quality time' in there.

It also helps that I am small enough in stature to be able to crawl into either the port or starboard lazarettes, wiggle around, and actually accomplish something while I am in there. Always my biggest fear when down in the lazarette (as I state in my article) is working with AC voltage, such as using a heat gun. Most of my tools are battery powered and therefore pose no electrical hazard; but the heat gun! Or the soldering iron! Being surrounded by potential grounds, any current leakage could 'fry' me in place. And who would know??? Therefore, I filed a 'flight plan' with my wife when I used the heat gun for the heat-shrink tubing. I told her that if she didn't hear from me in, say, ten minutes, that she should call for an ambulance. I told her to advise them that I might be electrified, and that they should remove AC power to the vessel before approaching the boat. (I also said that if this event happens, they probably wouldn't need to hurry.)

All this talk reminds me of the boatyard I used in my first few years of boat ownership (starting in 2004). There was a team of mechanics there: one was about 280 lbs and the other was about 5 ft 4 in tall and weighed under 120 lbs. Guess who got to crawl around inside the tight spaces?

I guess we need some others to chime in here with dates of production changes and hull numbers, but here is my take on this.

Mk I...original narrow stern, no transom walk-thru;
'Mk 1 1/2'...narrow stern, but with the walk-thru;
Mk II...broad stern, all with walk-thru.

Comments, anyone?

[QUOTE=LCBrandt;11258]
Mk I...original narrow stern, no transom walk-thru;
'Mk 1 1/2'...narrow stern, but with the walk-thru;
Mk II...broad stern, all with walk-thru.
Comments, anyone?[/QUOTE]

Having looked at a dozen 36s when we were shopping for ours last year (we ended up choosing a Mk I), I'll try to add to Larry's list (from memory) a few more of the major differences we noticed:

1) Tankage: The Mk 1 has the holding tank under the forward settee of the dining area adjacent to the head. On the Mk II it was relocated under the middle settee on the port side. Also, the fuel tank in our Mk 1 is under the aft settee of the dining area (just forward of the galley sink cabinet), in the Mk II I believe its somewhere in the aft end of the boat, correct?

2) "Furniture" changes: In the Mk 1, the aft cabin hanging locker is all the way aft, and the aft cabin entrance is closed off with a retractable curtain. In the Mk II the hanging locker was relocated to the forward end of the aft cabin (and drawers added), and the aft cabin was completely enclosed with a solid door and floor to ceiling bulkhead on the starboard side of the companionway ladder. This redesign also necessarily changed the seating at the nav station: in the Mk I the seat faces forward, in the Mk II the seat faces to starboard.
Also, the upper cabinets in the main salon on the Mk I reach to the underside of the deck, while in the Mk II they don't go that high and have a shelf on the top. Lastly, there are overhead lights in the Mk II over the galley sink, which the Mk I doesn't have.

3) hatches/ports: Unlike the Mk I, the Mk II has below deck deadlights between the cabinets in the salon (and one in the aft cabin), and opening hatches on either side of the companionway near the winches.

We checked out 2 Mk 1.5s during our shopping trips, and if I remember correctly 1 had the interior arrangement of the Mk I and the other the interior of the Mk II. I could be wrong on this, however).

[QUOTE=Capt. Sam;11264]Well, I dunno Mathew, but most of the "MKII" cabin configurations you listed are on my 1994 boat which is labeled a "C36". So I'm still a little confused.
But I'm pretty sure that the stern widening is a MKII feature. My boat has the pass through transom, (which I love) and the smaller stern. Again, my talk with the Catalina people in California said their was never a designation of MKI. It was just a C36, one or two cabin, and changes got incorporated all along until they got to a point (approximately in 1994, where they decided to make some hull changes in addition to the earlier ones and call it an MKII.[/QUOTE]

Nothing to be confused about, Sam. "We-all" are calling it a Mark I 'cuz when Catalina started making them they never knew they eventually would end up making a Mark II. It's us owners who have "dubbed" the original boats as Mark Is, and your boat with the narrow, but walk thru, stern is a Mark 1 1/2 - we have the same with our C34s. Also, we have a C34 Mark 1 1/4!!! It's a narrow stern with a small sugar scoop transom, with no opening! Imagine that. They only made a small handful of them, and one of our message board registrants has one.

Here are our examples: [url]http://c34.org/wiki/index.php?title=Miscellaneous/evolution[/url]

In your case, they're ALL C6s. Enjoy.

Sam,
You have a right to be confused. As you learned from the factory, they made and continue to make continuous improvements to all models. According to Gerry Douglas, in a past issue of Mainsheet, the first MkII was #1368, built in 1994. Yours is one of the last "pre-MkII's". Hope this helps.

[QUOTE=Capt. Sam;11323]Thanks for clearing that up. Its good enough for me. If I ever sell, I'm listing as MK1.5.[/QUOTE]

Sam -
Given Tom's data on where your boat fits in the sequence of C36s, sounds like you could list it as a Mk 1.75 !
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