Dropping the Tranny

Today I dropped the transmission in preparation for installing the new ACT clutch.   This process has been well documented in the following entries:

http://www.miata.net/garage/clutch/index.html

http://blog.richramblings.com/main/?p=1979

So, there’s no reason for me to redocument how this goes.  I’ll only add my own bits, where I differ.

 

First, tools…unless you are a brute, I strongly suggest getting an impact wrench and at least 18” of 1/2” extensions…preferrably 24”, and a impact universal joint, and 14, 17, and 19mm impact sockets.  Everything other than the impact wrench is absolutely mandatory.  I think the impact wrench is mandatory.  I’ve done this entire car with nothing but hand wrenches, I’ve broken a breaker bar, I’ve used two legs and both arms to get bolts loose under the car…so, I’m not opposed to hand wrenching.  But, the positions to get to the bell housing bolts are awkward and its very hard to get a good torque angle with the body and transmission case in the way.  I tried for an hour to get the bolts loose..before I finally conceded and ran to the box store to get the wrench pictured below.  The battery had to be fully charged to break the bolts loose.  I’m not sure how I’m going to get all the bolts started when its time to reverse course…but, that is a problem for another day.

 

P1010058

 

Once I had the power plant frame and propeller shaft removed, the trans and engine rock backwards.  Per suggestion from Dave Wheeler, I placed a 6” section of 2×4 between the crank pulley and the steering rack.  This prevents the engine from rocking forward while the trans is being removed and wedging the input shaft on the clutch.  Also once the trans is removed the engine will rock forward (without the 2×4)…and make it almost impossible to get the transmission back on.

One more thing…I followed the basic pulling the trans off the back of the engine…but, I found them lacking in particulars.  I fought with this for quite a while (over an hour).  I couldn’t get it to budge more than about 1/2 an inch.  I couldn’t figure out where it was binding.  Then I discovered one bolt that I’d missed.  Keep in mind that there are 11 bolts around the bell housing.  Some are very hard to see.  Count the bolts…make sure you’ve gotten all 11.

Once I’d found the last bolt…I still had some difficulty getting the trans to move more than an inch.  I had the trans tail suspended from a rope (per miata.net), and I had my jack placed just in front of the drain plug.  I found this location to be precarious, and ineffective.  So, I move the jack to the front edge of the bell housing.  There is a small flat up there, and it fits the jack quite well.   I raised the jack until it just made contact, then I pushed just a bit more watching through the bolt holes.  When the bolt holes were lined up, I stopped.  Then I was able to slide the transmission off the back of the engine.  I had to reposition the rope holding the tailshaft to make room for the moving tranny.  But, it came right off.

 

P1010044P1010060

Clutch exposed.  the impact wrench (my new favorite tool) made quick work of these.

P1010045P1010043

 

You can see quite a bit of oil in the inside of the bell housing.  My CAS is leaking pretty badly…guess that’s next.

P1010061P1010063P1010065P1010068

 

Well, on Friday, I’d been told by the machinist that he was open til 6pm on Saturday.  so, I ripped the flywheel off, and dashed off to the machinist.  He was wrong…closed at 3pm.  It was 522pm, and I was prepared to pay extra for someone to stay late.  <Sigh> no luck.  So, back to the house to complete some of the simpler tasks on the list.

 

Remove the thermostat:

P1010049P1010052

 

New water hoses, and alternator belt.

P1010054P1010055P1010057

Big day…I’m sore everywhere.  My neck from leaning up to see….my stomach from similar, and up and down on the creeper; my tailbone from leaning back on the creeper (I have a cheap wooden one).

 

Now, off the mazda speed to order a CAS o-ring, engine rear oil seal, and transmission front and rear oil seals.

Leave a Reply

You can use these HTML tags

<a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>

Connect with Facebook