How do you know where to turn the tension adjuster on the chaincase? (i.e. How many times do you back it off from the tightened position?)

just until the holes all line up to make it possible to put the linch pin through all the holes.

On a Polaris, you turn it in (clockwise) until you just feel it touch the chain, back off 1/4 turn, hold it and lock it.

SkiDooMXZ, handtighten the tension nut. Never use tools to doo this. Tighten it up and then loosen it up enough just to get the retainer pin back in. I find that with the long paddle track I have to adjust my chain often
To cut down on the amount of shrapnel inside the chain case. I use amsoil chaincase oil and Energy release. I find very little metal fillings anymore. It is more of a fine dust and the chaincase lube stays clean and clear just like water.

Perm

Thanks for the replies everyone.
P.S. What is "Energy Release"?

Here is a blurb on ER. I have used the stuff for three years now and will continue to use it. I am in no way connected to this company. :)

Energy Release (E.R.), a liquid product, is designed to drastically reduce the effects of boundary lubrication and therefore the major problems that this situation creates. The E.R. reduces the boundary lubrication effects by modifying the surfaces of any ferrous based materials which results in a glass smooth surface to those ferrous components. The Energy Release requires time, heat and pressure to work effectively and only those areas subjected to pressure and heat are treated. When this process is complete an engine or any machine which is lubricated, will run with greatly reduced internal friction which in turn results in less fuel consumed, less heat generated and an increase in power.

NEW HELP FOR AN AGE OLD PROBLEM.
Friction between moving metal parts is harmful to any machinery. Though they may appear smooth, metal surfaces are actually quite rough, microscopically, and friction between them produces heat and wear.

Lubricants slow the process of wear but do not stop it. Excessive heat breaks down a lubricant’s protective film, allowing metal to metal contact. This results in oil borne metal particles which act as a grinding compound, accelerating wear.

Most additives attempt to deal with this problem of friction from the outside, by increasing oil viscosity or by coating the metal. This is only a temporary solution.

Energy Release however, addresses friction from the inside, by dealing with the metal surfaces themselves.

ENERGY RELEASE TREATS THE METAL, NOT THE OIL.
A true friction reducing metal conditioner, Energy Release works on an entirely different principal than oil additives. ER incorporates a heat activated chemical technology that actually modifies the molecular structure of ferrous surfaces. ER mixes readily (but does not polymerise) with petroleum and synthetic lubricants - oils, greases, hydraulic fluids and diesel fuels- and is carried to heat and pressure points. ER seals rough pores and smoothes metal surfaces without changing tolerances. As a result, friction is dramatically reduced, heat is kept in check, metal wear rates decrease and that helps extend engine and machinery life.

ER is non-toxic and non-flammable. It contains none of the fortifiers commonly found in other conditioners and additives. There are no petroleums in ER, no Teflon, no moly, graphite or zinc.