I bought a mazdatrix ast couple months ago but im not to sure about the quality. I have looked and found plenty about pettit not being to good. Before i have the mtrix installed i want to make sure there isnt a better one. I have found some that look real good but seems the companies arent around anymore. Thanks
Grey

 

most of the ASTs for the FD are hot garbage made out of cheese, they warp and leak. the pettit for example, i usually had to replace those within 3 years due to the thin and junk flange pulling up and not allowing the cap to seat properly anymore.

next time i have an FD in the shop i'll make a prototype.

 

Had an aluminum AST on my first one. Honestly don't see what all the hype is about. Just buy a new OEM one. They're cheaper and will last the next lifetime of the car. My old was was 22 years old and still kickin. I'm sure my new one I put on will also last 22 years.

Matt

 

i rather agree compared to these alternatives that seem to not last. the only downside to the stock AST is that it is plastic and when it does fail, it fails spectacularly.

 

I also agree. I don't see how a stock AST would fail unexpectedly however. When I replaced mine, it was severely discolored. The moment my stock AST begins to change color, if ever in the next decade, I will again replace it :P

 

I dont think mine looks discolored like that one but it is the original one with 24k and some change on it

 

I agree and disagree.

I agree about oem being better quality than aftermarket but disagree about the lifetime of the car. If anything these things should be deleted. Best thing I ever did

 

I'm looking for an aluminum ast at the moment but you guys are swaying me to get a new stock unit. I just don't feel comfortable with the fitment issues of a/m asts vs oem.

 

^ Me too. Probably wouldn't have deleted it had it not been (sort of) forced on me by my choice of SMIC. But done PROPERLY I recommend it. I change coolant annually in the spring and really takes no more time bleeding the system now than it ever did. Little more room and one less hose.

 

The mazdatrix AST appears to be the Pettit AST without the Pettit name on it. Its crap. Send it back, and get a refund.

The tri point engineering ast is a good quality unit. I dumped my crappy pettit ast years ago, and got one from tri point. I suggest calling them.

(818) 348-5385

 

Thanks for the number adam c. I had found links to tri point but they were dead ends. Ill call them monday.

I was thinking the mazdatrix ast looked similiar to the pettit, but havent haf my hands on pettit ast to really tell. I was just going off pics.

To be honest im torn between stock and aftermarket(for the ast). I really want to keep the car close to stock since its all original.

 

Delete it. Cleans up the engine bay as well

 

Stock one from Ray is $100. Think it's like $10 more from mazdatrix. Just grab an OEM one and don't worry about it again for a decade.

 

You are the first person that I've seen on this forum to hint that the AST is a reliable piece of hardware. And I've been here prior to the crash....

The fact is that these things have been proven to be a failure point as they tend to burst and leave people stranded. Just because it hasn't happened to you doesn't mean that it hasn't happened to countless others.

 

yea you don't need it unless you don't know how to fill an FD's coolant properly (really the trick is to remove the throttle body coolant line when you fill, run the car a little with heater on, and repeat)

If you have the throttle body coolant line blocked off, then unblock it when you fill to allow air to escape.

IMO the AST just adds more failure points, not so much the AST itself, but several more clamped hose connections to leak. Its there to make the car more of a "normal car" in regards to maintenance i.e to make it easier for the general public / people who know nothing about their car to fill it.

 

Sure it's a failure point. Anything can be a failure point. Something is only as unreliable as you make it. I changed my AST and I don't see it spontaneously exploding in the next decade. If something last 22 years without exploding, I wouldn't call it unreliable.

Yea hose clamps can leak, yea lines can break or burst. But you know what? Mine aren't. Mine are all new. New lines, new clamps, and a new AST. I've changed thousands of dollars in parts on my rx7 because it's a potential failure point.

I just don't see what the big hype is in deleting things because it could fail.

Matt

 

The stock AST is a part that has failed many FD owners for decades. That's a fact, not conjecture. Just because yours hasnt failed, doesnt mean its reliable.

The problem appears to be its plastic construction. It simply doesnt hold up well to the high underhood temps that are commonplace with our cars. Over time, it gets baked and brittle. A good quality metal AST wont fail like the stock one has for so many of us.

 

i believe we've covered this, in this thread.

many "good quality" ASTs wound up in the garbage long before a new stock AST blew apart.

 

I understand that. I get it that the part gets baked and splits and then say goodbye to your coolant seals. But let's e critical here. How long do you think it will take for a brand new AST to spontaneously explode? I would guess ten years. But that's just me. Now does that make it unreliable? If something lasts 10 years I would say not. Why not look at an AST as more of a time change item, and less of a erratic accident waiting to happen. If you think it's gonna pop, change it. I promise it won't pop for a long time if you do. If you want an aluminum one, by all means. But when we're looking at it from a time change perspective, $100 for a new AST every 10 years is $.03 a day.

Man maybe I should look into an aluminum one. If that lasts for 20 years...assuming rust doesn't waste it...and its a $150 AST...makes $0.02 a day!

And Rotary Evoluion just said in post #2 that he's seen an aluminum one warp and be junk in 3 years.

Done beating this dead horse. Options are get an OEM one, get an aluminum one, or delete it. All cost roughly the same amount of money and all will be a fix for awhile.

Matt

 

Alright... so who has a new stock ast they want to sell? LOL

 

.....or just delete it. Easily done if you have a two piece filler neck, been covered many times here before

 

I have run a Tri-Point alloy AST for years as a daily driver car. They are the ones to go for because the filler cap neck is billet machined and thick. It will never give you any issues.

The stock plastic AST can be fine, or it can explode in half. You'll never know. I personally have seen an FD here in Australia that split its plastic AST in traffic and cost the owner the engine.

The other point I'd like to make is that not one post or person here has mentioned that the stock AST has a tiny 64th inch sized orifice in the bottom hose outlet to the radiator. This little orifice is the whole damn reason for the AST to be there. It slows the coolant down and keeps it stagnant in the AST longer, so any champagne bubbles can rise to the top of the AST and be bled out of the system continuously.
NO aftermarket AST tank has the same little 1/64" orifice in the lower hose barb, so by definition, NO aftermarket AST is properly engineered to be working correctly (slowing coolant down and trapping bubbles).

I made a 1/64" orifice pill and inserted it into the hose leaving the AST for the radiator, when I installed my Tri-Point AST. It is the only aftermarket AST that would be actually doing anything and working correctly. The rest of you guys are running aftermarket ASTs without the orifice and they are doing nothing for you....

 

Not necessarily....

 

The OEM hose that runs from the AST to the overflow tank has a plastic flow restrictor in it where it it splits in 2 pieces. I'm not sure what size the restriction is.

That's a nice looking AST Jim. Which one is it?

 

If someone throws away a good quality AST, that doesnt mean there was anything wrong with it. A high quality aftermarket AST wont blow apart. A stock one can. Thats a fact.