Does a TB change need a new crankshaft bolt. My old Mazda always wanted you to use a new bolt. I don't want to save 20 bucks and have to tear apart a crankshaft 6 months later. Also is there some sort of key that lines up the pulley and crankshaft that should be replaced also

 

I would replace the bolt...especially with the 217 ft/lb torque you'll be putting on it to install. The bolt head on mine was showing wear a good bit after being removed...and it didn't look like it was replaced the first go-around either. New one was $6 and change from the dealer. No worries re replacing the woodruff key as long as it's not damaged.

 

According to the FSM,the only non-reusable part in a T-belt change is the dipstick O-ring.

If you want to put a new one in there for piece of mind,sure replace it,But torque spec and a touch of loctite is way more important than a new bolt...

The Key is called a "woodruf key",Its a little half moon steel piece that sits in the crank,It should never need replacing unless the crank comes loose and damages it.

Personally I have probably done 100+ T-belts,not once ever had/or though I needed to replace a crank bolt,or woodruf key,The crank bolts are super strong...The do not strech like head bolts,they are not torque to yield type,proper holding tools,accurate torque wrench,drop of loctite,they will not come loose..........Its the idiot techs that put an impact gun on them for torquing(not near or accurate enough) and call it done..."Flat rate dictates"...