Ok been working towards rebuilding an engine on a friends car after a failure but wasnt expecting this. :o

This is the rear rotor and housing, As you can see in the pics the rotor has extensive damage as have the housing, all 3 faces are the same, the water chans have erroded right through to the water seals, looks like there is a jelly type substance in there as well, prolly some kind of rad weld.

This car has 60k on it and is 12 years old.

The other rotor is the same, maybe carbon buildup distroyed a tip that took out the rest.

 

Been looking at the pics and i think the corner seal spings are not standard ?

Also all the corner seals and side seals were stuck in and took some chiseling to get out.

Loads more pics if required.

 

ouch!

 

It'll buff right out.

 

Guess i better get buffing then

BTW is this a standard Spring as im thinking its not, if im right then this engine has been rebuilt before but very badly.

 

EEEkkkkkkkkk!!

 

Looks like an OEM corner seal spring.

 

Ive never seen one with that bad damage,,,lol what do the turbos look like?

 

Perfectly normal for a blown apex seal. One seal breaks while the engine is running, the pieces get wedged between the rotor and housing as the engine rotates and gouges the rotor and housing.

http://www.rotaryresurrection.com/3r...nt_damage.html

The corrosion in the coolant passage is a result of running too much water in the system...part of the reason we run a coolant mix is to prevent corrosion and pitting.

Everything about the corner seals looks stock to me.

 

Ah, just thought they were aftermarket as i though i recalled the atkins rebuild dvd mentioning these as an upgrade sping.

Think i could be mistaken here

Im almost sure the owner of this car drove hard uphill when the stock gauge was only just showing up to temp.

 

They are stock for 93+, and an upgrade for 91- engines.

 

Dont know yet as i havent taken them appart, the outer fins that are visable look ok and they seem to be running freely.

Just thought id mention that it looks like the rear rotor has blown then pices have been passed though the exhaust manifold to the fron rotor, is this possible ?

 

incorrect, the water jackets tend to break more than people seem to realize. the irons reaching 12-15 years old are becoming aged, worn and brittle. the castings are inconsistent so some irons are more susceptible to failures than some with good castings. the irons tend to break with more heat cycles(more mileage or years) which is why i see it more on FCs than i do on FDs so far since they have more miles and more years but one good overheat can crack a coolant seal wall on even a good low mileage casting because the material expands enough that the coolant seal pressure is enough to force the wall to break.

FDs do tend to have more issues with electrolysis in the rotor housings though, these are like little pits that look like someone was drilling on the rotor housing in the water passage, most susceptible areas on the FD rotor housings are around the spark plug jackets because Mazda decided to machine in this area and make the castings thinner.

 

Are standard apex seals 2 piece ?

 

Wow! that looks nasty!

 

yes, all original FD motors were built with 3(the main apex seal long piece is 2 pieces plus the corner seal boot makes it a 3 piece seal, all seals currently in production even OEM are now 2 piece seals) piece seals.

 

a one piece seal

 

holy **** batman thats bad. good luck with the rebuild

 

ouch, what was the boost- that had to hurt.

 

lmfao@spekdah

 

I opened up 2 engien lately and they were both with the OEM corner seals (rubber insert)
It tends to give me the impression that the rubber inserts are the reason for apex seals gettign stuck from time to time.

Is this true or not? Are solid corner seals better? I can imagine rubber melts faster than steel and thus messing up the apex seal position.

 

I've never seen any problems with stuck apex seals due to the 2 piece corner seals.

Spekdah, that's some pretty bad damage. That rotor is one of the worst I've seen. Looks like your buddy is springing for lots of new parts, lol.

 

Iv had a close look at the corner seals and they are very badly distorted on the inside edge to the rotor, the tips are also very hard to pry out of the rubber centre pice but that could have been due to the type of failure.

We are perchasing a second hand running engine to rebuild so not a great deal of the original engine will be used.

The tubos did poo themselfs, the inside fins on the rear turbo have been totaly abliterated, luckily the other motor has twins already on them, shame as appart from that the twins are in amazing shape.

One of the turbos may have survived, can they be interchanged ie. fron turbo put in the place of the rear turbo ?

 

Btw we are hoping that the second hand engine that we are perchasing to rebuild duznt have the type of currosion in the water jacket as the original did (as it has 47k miles on it) or we are back to square one.

 

damn that's ugly...

now that I think about it, you should have named this thread WHEN APEX SEALS ATTACK!