Sunday, January 26, 2020

Torque Trouble

Let's say you're inflicted with a near-terminal case of mechanical ineptitude. Let's furthermore say that you're working on a BP-ZE engine, popular in mid 90's Ford Escorts, Mazda Miatas, and a few other low-to-mid-range vehicles. Let's also say that you're at the part where you need to reinstall the camshaft caps.

Given these assumptions, I have some tips for you.
  • Your standard large torque wrench has numbers that go all the way down to zero, but there's a good chance that the minimum force it can handle is 20ft-lbs. If you try to use such a device to reinstall the caps, you'll shear your bolts off in the shaft and need an extractor kit to proceed. Get yourself a decent in-lb torque wrench for later.
  • Now you need replacement bolts. Your options are overpriced OEM units or going to the wreckers. The latter is more palatable, and will probably cost you $5 for a full replacement set.
  • It can be surprisingly difficult to find a BP-ZE engine at the wreckers. They're getting pretty old, and most of the Escorts and Protoges and such you find aren't quite the right trim to have the DOHC plant you're looking for. Good news: the plentiful, eighth generation of Mazda Protoges (1998-2003) has what you need. Undo eleven bolts on the valve cover to crack that sucker open (watch for the center bolt hidden under the ignition wires), and extract however many bolts you need. They're the same height, thread, and head size as those from the BP-ZE.
  • Take your bolts back to your engine, wipe them down (oily bolts, apparently, will bugger up your torque tolerances), set your new in-lb torque wrench to 100-125, and get your project back on track. That's assuming, of course, you can find the goddamn 10mm socket.
Now go forth, advice, and may the seas of Google carry you into the hands of those poor schmucks like me that have found themselves in a tough spot of their own making and ignorance.
-Cril

2 comments:

Frank said...

Yer a mechanic, Harry! When I was building my 350 motor, I was putting on the heads and my uncle gave me a book with the torque info. That book was wrong. I kept telling him and my cousin the shit felt like it was going to break and they were like are you fucking stupid follow the numbers.

PLINK.

Crilix said...

Wait, hol' up. The books/manuals can be wrong? Well there's a whole new level of anxiety I didn't know I needed.