These are notes and pictures from a recent timing belt & water pump change. I've written this mainly to document the steps I performed on my car so that I can go back and refer to it the next time I have to do this job. It wasn't really intended as a general how-to page. Over at Miata.net, consult with Gary Fischman's timing belt and water pump write-ups for a thorough description on how to do the job. Better yet, get a copy of Rod Grainger's Mazda Miata Enthusiast Shop Manual or Mazda's factory workshop manual for your model year.
My car is a '94 (B package) with air conditioning and power steering. It has a Racing Beat high flow air intake assembly. It also has a Racing Beat sway bar brace kit (which complicated things slightly). The odometer was 100,351. My car has never had the timing belt changed. My excuse for waiting so long is that I live in California and my factory manual says the timing belt replacement interval is 105,000 miles in our state despite having the same belt as Miatas in all the other states which have replacement intervals of 60,000 miles. Isn't this a great state or what? :-)
The goal by the end of the weekend was to replace the following parts and have the car start ok again.
I was feeling quite apprehensive at doing this job. I've never done a timing belt change before, and in fact, I've never even touched the front part of the engine on my car before. I've never tinkered with the cooling hoses, drive belts, power steering pump, or alternator, but on this job, I'd have to deal with all those things.
Also, I've never done a similar job on any previous car I've owned. The most complex job I've done on my car was a shock install, and later, a coilover install. But I decided to do the job myself, both as a great learning exercise (which turned out to be a very valuable one), the capability to control the quality of the work myself, and to save money on the install (one independent shop quoted me $240 to do exactly what I was going to do; a local Mazda dealer quoted $520 - and these were just labor costs). Parts were bought from Madaformance.com; prices were pretty reasonable and they were easy to deal with.
As an amateur wrencher, when I stepped back and looked at the effort involved, there's quite a lot of steps in the process process that makes it look daunting: remove Racing Beat sway bar brace, drain coolant, remove radiator fans, remove air intake crossover tube, remove upper radiator hose, disconnect 2 hoses from thermostat housing, loosen power steering pump and remove belt, loosen alternator and remove belt, remove cam cover, and then remove the 3 timing belt covers. It's only after you've gotten this far that you'll actually be close to changing the timing belt itself. Then there's additional work for the water pump and the camshaft seals. Then you have to go back and reverse the process and put everything back together again. Only when you've buttoned things up can you start the car to get the first inkling that you actually got everything put back together right. Whew!
In the end, things worked out well. Being the first time I had ever done the job, and being very unfamiliar with the pieces I was dismantling, I went slowly and the effort spanned the whole weekend. I was tired at the end, but very satisfied with the result and money saved. The car started great the first time. I had some initial squeaking sounds on cold startup, but that was fixed by tightening the alternator and ac/ps belts.
There's lots of useful tips on Miata timing belt changes thatr's been posted on the web and at the Miataforum site. I saved a few of the links below:
Gary's Miata.net write-up. Great. For the most part, this is what
I followed:
http://www.miata.net/garage/timingbelt.html
Some pictures:
http://www.brit.ca/~tboicey/miata/
Bad crank 1:
http://www.gvii.net/dlralt/installation_photos/071202_cams.jpg
Bad crank 2:
http://www.gvii.net/dlralt/installation_photos/071202_nose.jpg
Bad crank 3:
http://www.gvii.net/dlralt/installation_photos/071202_pulley.jpg
Timing belt changing tool
http://birminghamauto.net/cams/techtool.html
Keith's pictures:
http://keith.miata.net/belt.html
Brainstorm tools:
http://www.miata.org/cmt/bsp/content.asp?subcatid=23&catid=21&category=Tools
Rough pricing
http://www.sebringmiata.com/page75.html
Small mention of Miata
http://www.asashop.org/autoinc/jan98/timing.htm
Crankshaft failure
http://www.teammiata.com/libs/Miata_Crankshafts.htm
Various tips
http://www.fizzindi.demon.co.uk/cambelt.htm
Tip on aligning marks
http://www.miataforum.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=5;t=027312
More tips
http://www.miataforum.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=5;t=027025
Disconnect CAS before bump starting to loosen crankshaft bolt
http://www.miataforum.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=5;t=026978
More tips
http://www.miataforum.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=5;t=025508
90 and 94 crank issues
http://www.miataclub.org/orlando/xnosecrank/
Loctite on '90 crankshaft bolt from loctite engineer
http://www.miataforum.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=5;t=022286
2Twisty's pulley alignment instruction
http://www.miataforum.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=5;t=025824
More alignment tips
http://www.miataforum.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=5;t=025138
Tensioner pulley
http://www.miataforum.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=5;t=024714
Marks on pulley
http://www.miataforum.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=5;t=024611
Not necessary to pull radiator
http://www.miataforum.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=5;t=024187
Checking pulleys
http://www.miataforum.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=5;t=023792
Tip on removing splash pan, swaybar
http://www.miataforum.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=5;t=023703
Hakuna water pump change - good pictures
http://www.miata.net/hakuna/0057/aindex.htm
Tensioner
http://www.miataforum.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=5;t=023435
Questions? Comments? Send them to me at jaimev@panix.com