'89 Caprice Classic Tuneup+

Hey all, I'm new here at AF... Anyway I received a 1989 Caprice Classic (Brougham) as my first car, courtesy of my uncle. I love it, Caprices are a nice breed :wink:

Anyway when I received it, it was in moderate condition (interior preserved perfectly) but the undercarrage and engine block was covered in rust from being parked outside on the Eastcoast, and was in need of some engine work....

I have an autoshop class (I'm still in High School) so I brought it in for a tuneup and some general work...

So far I've...
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Replaced Spark Plugs (rusted near outer threads)
Replaced Distributer Cap/Rotor (carbon deposits)
Replaced Wires (brittle)
Replaced PCV Valve
Replaced PCV Filter (black & greasy)
Replaced Air Filter (black)
Changed Oil/Oil Filter
Bled Brakes
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I plan to replace the fuel filter (haven't gotten around to that yet) but I was wondering what else I should take a look at replacing/tuning/etc...?

I believe I read on the forums that it would be a good idea to dump the radiator fluid (not flush) and fill it up with water and run it through, dump that and refill with radiator fluid... Should I do this? If so how often?

I discovered a nice transmission fluid leak, shop teacher says the rear tranny seal is gone bad, but told me not to buy a new seal (he doesn't give explainations but I assume he thinks it's over my head?) However, theres just about no tranny fluid left and the leak increases when the car is jacked up unevenly... I've done some research and it seems pretty easy to replace, however I was wondering if it's any harder on an 89 Caprice..? I want to fix it as I can only imagine it'd get worse... (Any help or instructions with the process would be much appreciated)

Also something I could never figure out and never replicate at the right time, when starting the car up (sometimes) there'll be a rattling near the rear passenger underside sounds like metal hitting metal and it will continue if I backup/drive forward and it will stop after about 15 seconds... (catalytic converter perhaps?)

I'm a do it yourselfer kind of person, and I figured I'd get a second opinion (I know jack-squat about cars, but I'm pretty good with basic engineering) so this seemed like the place to ask :p

PS: Sorry for the long post; I tend to ramble and attempt to explain too much ;)

Welcome and good luck with the car, they aren't bad to work on and parts are very available.

The radiator: If the existing coolant is green and not contaminated, you can't go wrong with just draining the old coolant and refilling it with a 50-50 mixture. If you want to run water through it first, that would be ok but you may have to up the coolant to water ratio. Prestone makes an inexpensive coolant mixture checker that I always use when I change mine. Every 3 years is the rule of thumb for changing it.

Transmission seal: If this is the rear-most seal, it is fairly easy to change in most cases. You need to remove the driveshaft, pry out the old seal and install the new one squarely. Tapping it in with a hammer, I'll do that but you should use a seal installation tool that picks up on the whole face of the shell on the seal. I've used things like brake caliper pistons to drive them in or a handy piece of black pipe.

Your rattle: When the car is cold and not running, slide your hand ot top of the catalytic converter. The heat shield (if there is one) may be loose or the skin on the converter is deteriorating and flapping about. Also follow the pipe up towards the exhaust manifold, it might be heat riser related.

Bob