Well just recently my cars coolant seals seem to went , it was pretty sudden. I didn't realize they were gone until my brother really pointed out that the high amount of smoke from the exhaust smelled like anti-freeze ( i thought it was just unburnt gas).

Initially when i first installed my rebuilt engine, I overheated it several times because I didnt know the clutch fan was bad >.< I've driven the car for about 6 years and put 25k miles on it over that course of time, I always thought my coolant seals were going but never had any problems with the car starting up roughly, or blowing out smoke....

Now the car starts up everytime as if there is coolant inside the engine, even after i have driven it and just shut it off, it starts up roughly for a few seconds...

so I'm pretty sure the leak must be pretty bad...that and considering my coolant level dropped so low the coolant buzzer came on, the filler neck was bone dry, as if it had already sucked up whatever was in there, and i try to keep it filled.

so why would the seals just rupture all of a sudden ? After being fine for so long, as if the leak was a pinhole ?

Any way to temporarily fix, or better off just not driving? I think probably better off not driving considering possible engine damage, and it smokes so much id probably get pulled over.

 

Iron cracked at the seal support ledge...If the car is going through buckets of coolant, there isn't anything you can do. Drain the coolant out of the engine, dry out the inside of the chambers and then use a liberal amount of oil to flush out any remaining coolant. Otherwise you'll rust away the irons and rotors, making everything unusable.

 

is this normal ? what would make it do this, just being old and possibly warped ?

guess i should probably drain the fluids, and possibly start working on removing the engine >.<

 

The casting was a bit thin from the factory and with age, can corrode away.

It's something that needs to be inspected when the engine is torn down for rebuild. It is common in S4 irons.

 

it's common in all series, it's just more common in S4 because they are the oldest and most widespread of all series.

 

Well time is of the essence now. If you leave it sit it will rust. I've seen the inside of 3 engines that sat with broken coolant seals. Almost all of the parts were not salvageable, because it sat with coolant in the chambers, doh. Aaron's idea with the oil is a really good one if you're going to let it sit. No way to find out until you tear down the engine and clean and measure everything really.

When mine went out I still drove it for a few weeks and kept adding coolant. I think running the engine was better than letting it sit. One thing I love about these cars is that they are able to be driven even with a blown motor haha.

And one other thing, don't waste your time or money on block seal or whatever they want to call that "miracle" fix bs nowadays.

 

over rev can cause it to do so as well. redlining is the worst thing to do with a rotary if it is not built to take the abuse. as aaron said, the irons are probably thinned and cracked, but redlining or "racing" the engine can add to the problem.

do some surgery and let us know what you find...

 

that's a load of crap.

the seals die because of age, the irons die because of age and overheating them pushes them over the edge. but i have seen plenty of irons crack that have never been overheated a single time and can't count how many coolant seals blow out for no apparent reason aside from they were old and brittle and lost their pliability MANY years ago.

 

Is it highly noticable if the iron is on its way out ? I wasn't the one to rebuild the engine, Kevin Landers did the rebuild, tore it down right in front of me...you would think if the iron was that bad he would of told me I should replace it ?

I tend to drive hard on the car sometimes, i always enjoyed hitting the redline , i wouldn't say drove it like a race car constantly, but i did like to drive it hard...I figured it's a rotary, it's made to be redlined, I would rev it to 8k (limiter) a good amount of times.

How much time do i have to get this stuff out the engine before it's going to cause damage ? I will do it as soon as i can if it needs IMMEDIATE attention , it's just cold as hell outside...so im exactly looking forward to it.

Side Note - (may be importantant to the cause). Like i said , I did overheat my engine several times initially when I was a noob at rotarys (honestly still not a pro at all), but i overheated it like 2-5x to the point where coolant was boiling and coming out of the overflow when i shut the car off...this was due to a faulty clutch fan ( i thought i just did something wrong as far as bleeding the coolant system...man was I wrong) I fixed this problem with a new clutch fan, but afterwords i always seemed to lose coolant, but slowly...and it seemed air bubbles came out of the filler neck ( common for cars with a bad coolant seal).

Even when I bought this car, the reason I had to rebuild was because there was a hole in one of the irons from it overheating...so i would venture to say the housings/irons were previously overheated by the last owner

 

IMO it sounds like the seal has been giving out slowly over time since the overheat and it's now finally on it's way out. I also wanted to tell you that the engines I had seen corroded had sat for an unknown (many) months before I got to open them.

 

This is one reason why changing coolant is important. There are more reasons to change others than boiling/freezing point. They sell paper strips to check ph levels and stuff in coolant. Sadly most engines have sat for so long with **** in the passages the damage is done. I have taken a few engines apart where the seal edge was almost worn or was through on one or more irons.

 

So basically you're saying you should maybe yearly change/flush your coolant ? I'm not sure when the last time i did it was, the coolant in my car may in fact be the same coolant that was in the car 6 years ago, but with how much its been eating coolant, i would venture to say its drank the coolant i initially put in, because i've went through quite a bit, lately ive just added water to it.

what exactly does testing the ph level do ? whats it indicate ?

 

there is no way to tell how long an iron will last before the wall gives out around the coolant seal. even a rebuilt engine with 3k miles can still have a wall fail that looks perfectly fine during the rebuild inspection.

 

Ya changing the coolant frequently is a good idea to prevent rust. Racing Beat recommends 18 months, instead of 36, and a forum user with a very long lived engine did it every 12 months. If the coolant is brown you've certainly waited too long. Avoiding overheats and doing other related maintenance is important too of course. But if your engine is already leaking internally nothing short of a rebuild will save it.

 

Wow, that's shocking. It's really kind of scary to be honest, so if i get my engine rebuilt or get any engine rebuilt , it has a chance of pretty much going out in 3k miles or at least having the seals go out ? That's nuts!!

I love rotary engines, but man that really makes me think this is a big problem!

 

My car is sitting with a blown seal. How long do I have before **** starts getting rusted???

 

it always has been a problem and it sucks when you see reputable builders who have an engine only last a year after a rebuild when it technically isn't our fault that the engine just decided to give up shortly after rebuilding. granted it is much less of an issue having everything inspected and rebuilt than just running it with the already deteriorated coolant seals.

i'm working on a product to virtually eliminate the problem anyways.

 

Please pass the crack pipe.

A few weeks at the most. You should flush out all the coolant that may be in the chambers after draining the cooling system, then get some oil in there ASAP.

I have to disagree with the statement that they can fail at any time. Careful inspection can pinpoint a housing that is cracked or has weakened due to corrosion. Of course, there is always the possibility of some internal or unseen flaw, but again, careful inspection will minimize these problems. Engine parts should get an initial inspection upon removal, then another after first cleaning, then another after porting, then again after being cleaned again, then again after being cleaned to the spotless stage and made ready for installation. They can be magnetically checked with an inexpensive dye kit as well, if there is reason to think the casting could be damaged. And the area can be backed with epoxy though I'm not sure how effective that would be in the long term.

As always, your mileage may vary and different engine builders have different methods.

 

Sounds like the same thing that happened to my rx7 na->t2 conversion. It would start up and run for a few seconds and then die or if you applied the gas pedal you could get it to limp a few more seconds before dying. Had to pull the motor.

 

want to explain to me which shop is going to go through all of that work inspecting the irons that thoroughly at ~$750 labor to double the general 40 hour rebuild time and bump it up to more or less 60-70 hours for no more income? i like to actually have food on the table at the end of the week.

i know i have no plans on magnafluxing irons, if the walls are about to give up they generally will while cleaning the passage. you also can't tell me that even a single heat cycle won't crack an irons that was not cracked before no matter how closely you inspect it, these materials you are talking about are 20 years old.. if i have to dye test prior to cleaning, after cleaning and after porting you would have to expect to pay more for the rebuild, then you lose business to the guy who doesn't anyways. if you are referring to the DIYer then specify that, don't rub salt in wounds in an already hurting economy and tell me that my rebuilding techniques are weak, they are standard, standard to try to survive on these days. doesn't mean i don't honor my warranty and eat the occasional possibility that one does fail here or there, but that's a much easier route to go than wasting hours and hours looking at **** with a magnifying glass..

 

I didn't intend to question your engine building techniques. I was under the impression that this was a Landers engine, not one of yours, so I did not phrase my statement as if the builder was present.

I had intended to give my point of view that with careful inspection, cracked cooling jacked problems can be minimized, though of course not eliminated. A known weak area, having signs of potential failure, should be inspected carefully and the iron discarded if there is any question.

Yes, I go through a similar inspection process that I outlined with every engine I build. Truthfully, that isn't a lot of engines because I rarely build them for someone else, and have only built one for myself (to be two pretty soon...). All in all, about 10 engines to date are "Aaron Cake" engines and they range from stock ports to peripheral ports. Would I expect an engine shop to do so? I don't know. I didn't say that every iron should be magnafluxed, only those that might be in question, and if they are so much in question, they probably are too much of a risk to use anyway. If you reread my post, you'll see that I did not suggest an engine be magnafluxed at every step. And how long really does it take to inspect that known weak area at every step? Another few minutes with good lighting and a magnifying glass? It may not be some builders habits to clean parts so much, they may just lightly wipe off a set of irons, then port, then clean, then assemble. But I have always given them an initial cleaning after disassembly, a thorough cleaning and inspection prior to porting, another cleaning prior to paint, and then another soap and water wash after paint. Yes, it is a hell of a lot of work and not practical when someone is only willing to pay $750 labor for the whole process. And that is probably why I don't build engines. I could never make any money building engines for people because it is unlikely they would agree to my price.

As I said, different builders have different techniques.

 

i wasn't trying to sound as angry about it as it came off to sound, just main point is that mazda dropped the ball with the castings. i'd say about 90% of the castings have walls that are too thin in at least one spot. it's just irritating knowing that no matter how thorough you go through inspecting them that such a thin wall can give up without any warning. i do believe epoxying the thin walls does help and i did do it for a while but stopped. you simply can't be too picky just because the walls are thin on some motors or you will find out just how short the supply is for good casting irons out there.

this wasn't one of my engines but i have had one come back in about 125-ish that i am about to tear down and find out if it did in fact break a seal wall in right around the 1 year mark of run time.

the 13B castings are the same as the old 12A castings, they were never intended to have seal grooves in the irons. mazda just tossed them in there without any modification, which was obviously needed if they wanted a more durable engine to last over 100k miles without worry of breakage. but they did save that $.20 per vehicle in production costs by not having to adjust the iron casting process..

 

No worries...has anyone ever found out why Mazda swapped the coolant grooves with the 2nd gen after having them in the housings so long? I asked some Mazda people years ago but they didn't seem to know.

 

they had issues with the aluminum walls getting eaten up during some returns so they decided to change the design into the irons which probably lasted as long as their testing allowed, not knowing that they would start having serious issues after many years of heat cycling turning the metal into basically glass.

i could envision that would have been an issue but only in cases where coolant sat dormant in engine for a long period of time and coagulated and acidify over the aluminum.