Can't Find Drain Plug on '93 B2600i
 

My '93 B2600 runs hot during the summer. I probably need to replace coolant and perhaps the thermostat. Where is the drain plug located? I read that it is hidden behind a square or rectangular panel on the radiator - drivers side. I can't find it. Can anyone give me specific instructions? By the way, I'm not mechanically inclined. Please be elementary and specific. Thx.

First question: does it run hot only around town in traffic, or only out on the highway?

If (1), then the fan clutch needs to be replaced; it sits just under the fan blade, simple bolt-on.
If (2), may be radiator issue.

Are you losing coolant at all?

You won't lose much coolant just changing out the thermostat. And that's a good first thing to do, as that's under $10. A replacement radiator cap is also inexpensive.

Changing out the coolant won't help with your running hot issue, but will help maintain, lubricate, and protect a decent cooling system from corrosion. To drain out the coolant, easist way to simply remove the lower radiator hose where it attaches to the bottom of the radiator, no kidding.

I replaced last year the radiator on my '88 B2200 because it was running hot on the highway, Arizona heat, using AC, and it hasn't run warm ever since. By the way, if it comes to that, replacing the radiator is a bolt-in as well, should take even an inexperienced owner only 1.5 hours with simple metric hand tools. When replacing the coolant, I'd jack up the front of the truck and run the engine a few minutes with the radiator cap open, topping off the coolant (50/50 mix) as necessary, to get all the air out of the system.

If you really want to know where the radiator drain plug is, ask the question on mazdatruckin.com. A guy there named Earl has photos of everything !!!

My 2600 runs hotter than normal on the highway, but approaches the danger zone when idling in traffic. I'm in the Memphis, TN area. I don't run the air conditioning, which leaks freon. The radiator does not leak coolant. Been running the same coolant for a decade or more.

Replacing the thermostat was my next question. Can you direct me to simple instructions on how that is done? Remember, I'm not a mechanic. Far from it. Thx.

Oh...and how do I replace the fan clutch? Thx.