What can I mod to make the rex last?

[Brett]

Thanks Kevin,

 It is an FD, but its got around 48,000miles on the engine so I suspect its going to go pop before too long anyway, once that happens I\'m going to go through the engine bay with a tooth comb and replace all the dodgy/old hoses and components with new ones, so its likely I\'ll do the AST then.  Unless of course it starts giving my gyp, in which case it will be rectified.

[Martiny]

I think this is all good advice. Kevin is right, the easiest, cheapest, and most important mod you can do, is to replace the plastic AST with a metal one.

I believe the perceived 60k lifespan for an FD engine is codswallop!!!!

Now, it seems to me that you are taking reasonably good care of your car, and therefore its unlikely you thrash it and abuse it.

I think a new FD, driven sensibly, and properly maintained, unmodified (except for perhaps the AST) will last 100k.

Of the engines that we hear of going bad, how many were standard cars? I\'ll bet not many.


I too, used to race an RX-2 in South Africa, and here\'s what I modified - - -NOTHING!  And my engines, that I built myself, lasted 5 years, and I am no mechanic!

Take any car, bounce it off the rev limiter regularly, do lots of burnouts, dont warm it up (and down) gently, start fooling around with the fuelling/Turbo/Inlet system/whatever... would you really expect more than 60K?

I think you have a long way to go before a rebuild  :-)

[Brett]

Martiny,

 I hear what your saying, but I\'ve only owned it a few weeks, so theres no telling what sort of treatment it was given in Japan.  But the lack of mods on the vehicle is quite heartening.

 So the AST can cause major problems then, was this fault rectified on later models?

[Martiny]

Welcome to the way of the Rotor!  
Ok, the AST is the Air Seperation Tank, and its part of the cooling system. The plastic ones eventually split, then coolant loss - BIG problem on a Rotary - dont EVER overheat it - not even once, the housings get damaged, and its rebuild time.

It is a little tank holds maybe 1/2 litre of water. If you stand looking into the engine bay, find the Intercooler - a radiator looking thingy, sort of in line with the headlights,  - mounted on the top right of the Intercooler you should find the AST. See what its made of.

I dont know if Mazda updated them later on, anyone? What year is your car?

You can get a metal one from maybe ReWorx or  WGT Autos. I suppose around £150 or less.

[Brett]

The FD is an R2 made in November 1994, has an Apexi CAT back exhaust, other than that its standard.  Theres no sign of stressing on any of the tanks and expansion bottles at the mo\' but I will get a metal one made up all the same. (Because there is no way I\'m going to pay £150 for £5 worth of stainless steel and £25 of labour!)

[Carl]

Originally posted by Brett
The FD is an R2 made in November 1994, has an Apexi CAT back exhaust, other than that its standard.  Theres no sign of stressing on any of the tanks and expansion bottles at the mo\' but I will get a metal one made up all the same. (Because there is no way I\'m going to pay £150 for £5 worth of stainless steel and £25 of labour!)

Hi Brett,
the replacements are usually Alloy.
I can get them cheaper than that price.
Kind regards
Carl

[andrewrx7]

Originally posted by Martiny

I dont know if Mazda updated them later on, anyone? What year is your car?

Hi there, hope your pleased with your RX!

Just got my new RX,  a 2002 Spirit......the AST looks exactly the same as on my 92 RX I just sold! So I guess it has never been updated by Mazda.


I might say, when I bought my 1st 3rd gen (UK), 5 years ago, it was a very close call as to whether we would actually buy one or not, after reading about the unreliability etc associated with these cars. We decided to anyway, after seeing one - looked fantastic close up! It is a quick car anyway, and we didn\'t want to have it as a money pit, so we decided to keep it standard - the only thing having been done to it was the 1st pre-cat removed, a K&N panel filter added instead of the Mazda paper one (therefore std airbox), an extra cold air pipe fed into the airbox, and a switch added to turn the fans on after the car was off (to blow cool air through the engine bay).

And to be honest, the car had been superb. It had originally gone to 82K miles before low compression, and on the rebuild it had covered an additional 40Kmiles before I sold it on. One dead battery and thats been it. Started 1st time, everytime, hot or cold, winter or summer. Never missed a beat, as they say! Over the 5 years we had it, it had been a paragon of reliability!

As Martin says, as with any vehicle, surely if you abuse it, it will fail far quicker than if you use it wisely, and enjoy it occasionally. I guess it boils down to how big are your pockets - if you can stand regular repairs etc, then reliability is maybe not a high priority so therefore abuse away! We kept ours pretty much std, and looked after it, and its still going strong today! Co-incidence? Who knows........!!


Anyway, good luck with yours, and hope it carrys on for many more 10s of Ks!

Cheers,
Andrew

[Carl]

Originally posted by andrewrx7
Hi there, hope your pleased with your RX!

Just got my new RX,  a 2002 Spirit......the AST looks exactly the same as on my 92 RX I just sold! So I guess it has never been updated by Mazda.


Cheers,
Andrew

Just ammended my post!Meant the replacment AST tanks,not later Mazda ones.
Kind regards
Carl

[Brett]

I think you gentlemen have covered it all!  I have a decent fan setup on the Egi which I will copy onto the FD, it keeps the fan goins until water temperature is down below 75deg.

 Carl,

 How much are your AST tanks then?

[bnaellis]

The problem wasn\'t directly the ast tank it was the amount of pressure the system was pressurised to. can\'t remember jack at the mo due to serious lack of sleep but 1.2 bar I believe it was on from late 94 onwards mazda kind of did a recall of some of the bodges on earlier models and made them .9 bar.
As far as I am aware there has been no exploding ast tanks on fd\'s at this pressure but i\'m suspect some unlucky soul out there will post and prove me wrong.

rgds

[Brett]

Hmmmmm...mines late \'94, when I get it off of this island and back to the mainland I will get it in the workshop and hook a pressure guage up to the AST entry, and check a few other areas too.  If its 1.2 I\'ll get a replacement asap, if its .9 I\'ll hold on for awhile.

[Brett]

Hmmmmm...mines late \'94, when I get it off of this island and back to the mainland I will get it in the workshop and hook a pressure guage up to the AST entry, and check a few other areas too.  If its 1.2 I\'ll get a replacement asap, if its .9 I\'ll hold on for awhile.

[antnicuk]

the water sytem cap will have the pressure rating on it. I think it was 1.3 and changed to 0.9 bar.

I have yet to meet an FD with a genuine 100k on the original engine.  Unless someone has bought it from new or has a very comprehensive history then you will never know if it was rebuilt early on its life.   60 k seems to be about the avg.

There seems little point in leaving the fans on after the engine is off as this will only cool the air in the radiator and the water will not circulate around the engine,  the only time this is worth doing is if you have an electric water pump.   I fitted one, they are a very good mod and allow you to turn the ignition on (and the fans) and cool the water temp down extremely quickly.  (from 90 to 60 degrees in a minute or two).  Good for queing at the pod!! or stand still traffic jams.  Only down fall with them is the constant worry it may not be working, ie fuse blown.  Sometimes not worth the paranoia as once its over heated its fduk\'d and a more expensive rebuild than normal.   I suppose it may cool it down a little if the cooler water in the radiator drops and draws hot water from the engine but not a lot a would think.

[Brett]

Hence thats why I do a slow mile before getting home, lots of nice cool air and no load on the engine.  Then about 5-10mins at idle to cool the turbos down before shut off.

[Martiny]

I think one benefit of leaving the fans running (even without an electric water pump) is to reduce the amount of residual heat build up. IE - reduce heat soak after you have stopped the car. This would help prolong the life of the vacuum tubes, and I suspect many other things, too.

I just open the bonnet for a while if I stop after driving it hard, or after a long trip.  You can force the fan to stay on by leaving the key on, with the Aircon button on.