jordanjerome

I have an 05 AT and the cat was bad. it created so much back pressure that my rotor closest to the firewall is not working and has no compression at all. The Mazda dealer said the engine will need replacing. However its no longer under warranty. My question is why would back pressure blow the motor. I mean I have never once blown any motor in the 20 years I have been driving. Are rotary motors really that weak. Cant they just replace the back rotor and housing for a lot less then the 4700 they said it would cost to replace it. I am almost done with Mazda and rotary engines. this is the second one that has blown. The first was because the apex seals went out. Thats another thing, WTF it with Mazda not just fixing these. I asked a performance shop what they would have done with bad seals on an RX7 and they said just replace them but not the engine. I dont get it is Mazda no longer trying to care about their customers. I think they just want money. Anyway sorry to ramble but what are my options? I think replacing the whole motor is a crazy thing. But when I get it fixed I might be done with this car and company once and for all.

Old Rotor

Please give us the history on your car. The service it's had parts replaced. Type of driving it gets(long commutes, short trip), fuel used(reg or prem), ever flooded. Just any thing that you can add. What mods... miles? You must have over 100K miles, because the engine has a 8yr - 100K warranty.

jordanjerome

replaced plugs, wires, coil packs, after the cat-converter went bad and caused engine to cease. 106,000 miles but only 45k on second motor. always use 91 octane, royal purple oil 10 w30, never flooded. racing beat intake and exhaust. long commutes and well kept. is it possible that the rotor slipped off the eccentric shaft? was leaving my house. always warm the engine before moving never take off cold. got about a mile down the road. went to go at the light, heard a pop and lost power and engine stopped.

Cf05

unfortunately that is why your motor is no longer under warranty... I would see if I could find a motor out of a car that's perhaps been in a rear end collision and do the swap, maybe your local junkyard has one who knows you may get lucky? youll want to do a compression test on the new motor obviously but thats cheaper than having mazda do it... just my 02 cents

nycgps

iTrader: (1)

When cat fails(usually because the higher than usual exhasut stream). It breaks up, and clog the stream.

Why usually the rear fails. It has a lot to do with the way the coolant flows.

Why cant mazda dealership fix the engine themselves? Because most dealers have no idea how to fix it these days. Not to mention, the labor would properly cost more than whats worth.

And your local rotary tech is half right. It could be rebuild
But it really depends on what and how did it blow. Not to mention when a 13b-msp blows, 90% of the time it will trash the housing, rotors, int and side housing. But that has to do with its side port exhasut design. Older rotary use p port.

Rotary engine is not weak, its just different. When things are different, people love to blame them.

jordanjerome

thank you all for your advice. I have been reading the forum and a lot of people are on engine number 3. why is the rx8 motor so much weaker then the rx7?

9krpmrx8

iTrader: (46)

FD 13B REW's were known to blow up all the time from overheating.

jasonrxeight

its not the engine is weak, its only people ask when problems happen
if I was you I would get extented warrenty

as for FD owners, they probably just rebuild the engine themselves. nothing to blame about cuz blaming doesnt do anything.

to OP, its either you do the job or ask a mechanic drop a working engine for you.

jordanjerome

UPDATE

Ok all thanks for the advice here is the news.

New engine installed with hollowed out CAT, car before motor blew up was getting crappy milage and power loss. now with the new motor I am still only getting 145 miles to a tank and it runs terrible around 2000rpm and feels like I still have a power loss. The hollowed out cat is not throwing a CEL what so ever and the dealership is at a loss on what to do. could the milage/ power loss problem be caused by the fuel injectors or pump? Any advice is appreciated. I do know others who have a delete pipe and even with a CEL theirs run just fine.