Woody wrote:
Okay...I have the front of my engine stripped down to change the water pump and timing belt. I have a dial indicator with a magnetic base, but I'm not sure what the best way is to measure the crankshaft endplay with the engine and transmission in the car. I can tap the crank nose rearward with a polyurethane mallet, but what's the best way to move it forward? Will pushing the clutch pedal in be enough? I really don't want to put a prybar behind the pulley.
Should do. Doesn't take a lot of pressure to move it. You're really only fighting the seals and the lateral drag on the other (oiled) bearings.
Just thread the bolt back into the crank and try to move it by hand. Even if you're a feeble non-strong SOB, if the thrust bearings were wiped out you could give it some seriously clunking back and forth. I've never seen thrust bearings that were only a little worn, they have always been either .005-010" endplay (barely noticable) or an eighth of an inch OMG WTF CLUNKMEISTER play.
In reply to Knurled:
I actually tried that and there was no discernible movement. I was ready to quit there but figured that I should probably try a little harder before I proclaim that all is well.
In reply to Keith Tanner:
Thanks Keith. That's the plan for the morning.
Incidentally, for anyone tackling a Miata timing belt / water pump job, I highly recommend this book. There are a few things in there that the Haynes manual misses, like the fact that you need to remove the 21mm crank bolt in addition to the 10mm bolts before you can remove the crank pulley on later cars.
I've finally finished up the timing belt job.
I measured the crankshaft end play while I had everything apart. In the thrust bearing TSB, Mazda says that you want 0.3mm or less, which is 0.012 inch. According to the Haynes manual (general specifications, no mention of a thrust bearing issue), end play spec should be less than 0.008. I checked mine a couple of times and kept coming up with 0.0045, so I'm pretty happy with that. I guess that at 114k miles, I don't really have to worry about this particular problem.
Swank Force One wrote:
Woody wrote:
I never paid much attention to NB's before, but I just bought one. So...what's going on here?
http://www.miata.net/garage/tsb/sb00-01-014r-808r2.pdf
Uggh. So for a '99, what's the best year bottom end to swap in?
Naturally aspirated, 2001-05. Gets you 10:1. Turbo, depends on whether you want more power and less response (1994-95, 8.8:1) or more response and less power (1999-00, 9.5:1). If you use the 94-95 engine, you'll have to swap the oil pump so you can mount the crank position sensor. 1996-97 is 9:1 and has the sensor mount.
The thrust bearing problem engines are all gone now other than maybe a few very low mileage "collector" 10AE models. I would worry about a 99-00, but I'd stay away from a 96 due to the chance of a stuck oil pressure relief valve. Not as well known, but the failure is a lot faster and it can happen later in the car's life.
