RX-7 woes...
12-29-15, 10:39 PM
#26
Well I've talked to three different shops so far and every single one has said they don't have the time to rebuild it and suggested just swapping it with another running 13b. My only thing is if I swap in another running engine, what's to say that it won't just blow out in another month? At least if I rebuild this one, I won't have to worry about it blowing out for a while. And I've gotten on the car a lot harder before with no issues, so it's not just because I went wide open with it. I'm assuming a combination of mods on stock ECU and the fact that it's a 1992 took their toll and wore it down.
12-29-15, 11:44 PM
#27
A replacement engine might come [much] cheaper than rebuilding a blown one depending on the extent of the damage and parts in need to be replaced, plus the labor. But of course there's a dark side of going with a used engine, as you said you'd not know how long it'd last other than sticking with current compression numbers.
12-30-15, 07:50 PM
#29
bcrotary.
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Well I've talked to three different shops so far and every single one has said they don't have the time to rebuild it and suggested just swapping it with another running 13b. My only thing is if I swap in another running engine, what's to say that it won't just blow out in another month? At least if I rebuild this one, I won't have to worry about it blowing out for a while. And I've gotten on the car a lot harder before with no issues, so it's not just because I went wide open with it. I'm assuming a combination of mods on stock ECU and the fact that it's a 1992 took their toll and wore it down.
01-03-16, 09:30 AM
#30
Well I've already found a complete how-to guide for pulling the engine and have someone that'll help me tear down the block, plus several people I know at the shop that'll help me with pulling the motor, so I'm gonna go for the rebuild myself. I like to be able to say I did the work to my car, plus I wanna go in auto mechanics when I graduate, so this'll give me some experience. I know it's cheaper to just stick in another engine, and I do plan on doing a 20b swap, but I can't ship the car back to the US with a swapped motor and I won't be going back to the US for two years. And I don't want to blow another 13b like I did this one and end up spending even more, so I'll just rebuild what I have and have a "new" engine by the time I'm done (hopefully by spring).
01-03-16, 09:46 AM
#31
you should source another REW while you're there and keep it on the side
my first rebuild was nowhere near straightforward so spare parts or a backup engine is always good to have. i also assume they are relatively cheap there compared to here, where it's a crap shoot for a $2000 used engine.
everyone would love a 20B but i bet they're pricey there now and getting harder to find. i also tried to find someone who was willing to import them but they aren't exactly falling out of trees even in japan.
my first rebuild was nowhere near straightforward so spare parts or a backup engine is always good to have. i also assume they are relatively cheap there compared to here, where it's a crap shoot for a $2000 used engine.
everyone would love a 20B but i bet they're pricey there now and getting harder to find. i also tried to find someone who was willing to import them but they aren't exactly falling out of trees even in japan.
Last edited by RotaryEvolution; 01-03-16 at 09:50 AM.
01-03-16, 10:14 AM
#32
Do you know how much you were boosting when it popped? A boost gauge is a simple cheap and easy install. This would allow you to shutdown, or quit boosting if you notice overboost which will save your next engine. If you do build the engine yourself, take your time and make sure you use all documentation available to ensure it is correctly built. Cleanliness and organization is a must and make sure you have the funds before you start. Good luck
01-03-16, 09:26 PM
#33
Installing a used engine with good compression isn't necessarily better or worse than what you are going to do.
01-04-16, 09:28 AM
#34
you should source another REW while you're there and keep it on the side
my first rebuild was nowhere near straightforward so spare parts or a backup engine is always good to have. i also assume they are relatively cheap there compared to here, where it's a crap shoot for a $2000 used engine.
everyone would love a 20B but i bet they're pricey there now and getting harder to find. i also tried to find someone who was willing to import them but they aren't exactly falling out of trees even in japan.
my first rebuild was nowhere near straightforward so spare parts or a backup engine is always good to have. i also assume they are relatively cheap there compared to here, where it's a crap shoot for a $2000 used engine.
everyone would love a 20B but i bet they're pricey there now and getting harder to find. i also tried to find someone who was willing to import them but they aren't exactly falling out of trees even in japan.
Do you know how much you were boosting when it popped? A boost gauge is a simple cheap and easy install. This would allow you to shutdown, or quit boosting if you notice overboost which will save your next engine. If you do build the engine yourself, take your time and make sure you use all documentation available to ensure it is correctly built. Cleanliness and organization is a must and make sure you have the funds before you start. Good luck
Age doesn't blow motors. Let's just assume that one of your injectors is flowing far less than it should which caused your engine to run lean enough to detonate and break an apex seal. You get your engine all rebuilt and perfect...drop it in...finish the break in miles.... open it up... bang, right back where you started. Like I said earlier: If you don't know why your last engine failed then you don't have any business rebuilding one yourself.
Installing a used engine with good compression isn't necessarily better or worse than what you are going to do.
Installing a used engine with good compression isn't necessarily better or worse than what you are going to do.
01-04-16, 09:28 AM
#35
Couple things...
1) You are aware that a "rebuild kit" doesn't include new housings or rotors, right? If the rotors or housings themselves suffered any trauma, they will need to be replaced. Figure, I dunno, $300-$500 per housing and a little less per rotor. Expect at least one of each to be toast... maybe all of them.
2) Like everyone else said, if you're not addressing the issue that caused the motor to blow in the first place, you will blow your motor again. Rebuild, drop-in, brand new from Mazda, it doesn't matter.
3) A $500 Power-FC is a lot less pricey then another rebuild.
4) Very little in the actual cost of doing a 20B swap in the motor itself. Budget $20K-$30K to do it right. If a Power-FC in pricey.............
5) I like the idea of buying a take out, installing it, and getting your car running; you're doing the work, so you can still say "you did it"... THEN rebuild the motor that's currently in your car and hold onto it for a backup or sell it off.
I wish you the best of luck... but man, an RX-7 is a tough first car to own (trust me, I'm speaking from experience). Especially on a tight budget. Good luck.
1) You are aware that a "rebuild kit" doesn't include new housings or rotors, right? If the rotors or housings themselves suffered any trauma, they will need to be replaced. Figure, I dunno, $300-$500 per housing and a little less per rotor. Expect at least one of each to be toast... maybe all of them.
2) Like everyone else said, if you're not addressing the issue that caused the motor to blow in the first place, you will blow your motor again. Rebuild, drop-in, brand new from Mazda, it doesn't matter.
3) A $500 Power-FC is a lot less pricey then another rebuild.
4) Very little in the actual cost of doing a 20B swap in the motor itself. Budget $20K-$30K to do it right. If a Power-FC in pricey.............
5) I like the idea of buying a take out, installing it, and getting your car running; you're doing the work, so you can still say "you did it"... THEN rebuild the motor that's currently in your car and hold onto it for a backup or sell it off.
I wish you the best of luck... but man, an RX-7 is a tough first car to own (trust me, I'm speaking from experience). Especially on a tight budget. Good luck.
Last edited by MattGold; 01-04-16 at 09:30 AM.
01-04-16, 10:34 PM
#37
Couple things...
1) You are aware that a "rebuild kit" doesn't include new housings or rotors, right? If the rotors or housings themselves suffered any trauma, they will need to be replaced. Figure, I dunno, $300-$500 per housing and a little less per rotor. Expect at least one of each to be toast... maybe all of them.
2) Like everyone else said, if you're not addressing the issue that caused the motor to blow in the first place, you will blow your motor again. Rebuild, drop-in, brand new from Mazda, it doesn't matter.
3) A $500 Power-FC is a lot less pricey then another rebuild.
4) Very little in the actual cost of doing a 20B swap in the motor itself. Budget $20K-$30K to do it right. If a Power-FC in pricey.............
5) I like the idea of buying a take out, installing it, and getting your car running; you're doing the work, so you can still say "you did it"... THEN rebuild the motor that's currently in your car and hold onto it for a backup or sell it off.
I wish you the best of luck... but man, an RX-7 is a tough first car to own (trust me, I'm speaking from experience). Especially on a tight budget. Good luck.
1) You are aware that a "rebuild kit" doesn't include new housings or rotors, right? If the rotors or housings themselves suffered any trauma, they will need to be replaced. Figure, I dunno, $300-$500 per housing and a little less per rotor. Expect at least one of each to be toast... maybe all of them.
2) Like everyone else said, if you're not addressing the issue that caused the motor to blow in the first place, you will blow your motor again. Rebuild, drop-in, brand new from Mazda, it doesn't matter.
3) A $500 Power-FC is a lot less pricey then another rebuild.
4) Very little in the actual cost of doing a 20B swap in the motor itself. Budget $20K-$30K to do it right. If a Power-FC in pricey.............
5) I like the idea of buying a take out, installing it, and getting your car running; you're doing the work, so you can still say "you did it"... THEN rebuild the motor that's currently in your car and hold onto it for a backup or sell it off.
I wish you the best of luck... but man, an RX-7 is a tough first car to own (trust me, I'm speaking from experience). Especially on a tight budget. Good luck.
2) I've said several times my best guess as to why the engine blew: mods, stock ecu, rotary engine, twin turbo, 23 year old apex seals, and possibly was driven hard by the previous owner and me.
3) I know, which is why I'm getting one when I get my car going again.
4) I can't ship the car to the U.S. with a swapped motor, so I have at least two years before I'll even start considering the 20b swap.
5) I'd love to do that, but I don't have the money or time to buy another engine and be swapping them back and forth. I work part-time and all my hobbies are too expensive (snowboarding, drifting, and paintball).
It's not my first car, my first was my FJ80 that I still own (being stored in the States while I'm over here). Then over here I had a 300zx (sold it a few months later), and now I have my 180sx drift/track car and my rx-7 for my daily. Usually I don't really have a tight budget, but when I bought the rx-7 it cost me most of my money, and now this **** storm has happened before I could get my money built back up.
Keep in mind that I'm in Japan though. I can get a running 20b Cosmo for less than that over here...
01-04-16, 10:37 PM
#39
1) I know it doesn't include rotors or housings.
2) I've said several times my best guess as to why the engine blew: mods, stock ecu, rotary engine, twin turbo, 23 year old apex seals, and possibly was driven hard by the previous owner and me.
3) I know, which is why I'm getting one when I get my car going again.
4) I can't ship the car to the U.S. with a swapped motor, so I have at least two years before I'll even start considering the 20b swap.
5) I'd love to do that, but I don't have the money or time to buy another engine and be swapping them back and forth. I work part-time and all my hobbies are too expensive (snowboarding, drifting, and paintball).
It's not my first car, my first was my FJ80 that I still own (being stored in the States while I'm over here). Then over here I had a 300zx (sold it a few months later), and now I have my 180sx drift/track car and my rx-7 for my daily. Usually I don't really have a tight budget, but when I bought the rx-7 it cost me most of my money, and now this **** storm has happened before I could get my money built back up.
Keep in mind that I'm in Japan though. I can get a running 20b Cosmo for less than that over here...
2) I've said several times my best guess as to why the engine blew: mods, stock ecu, rotary engine, twin turbo, 23 year old apex seals, and possibly was driven hard by the previous owner and me.
3) I know, which is why I'm getting one when I get my car going again.
4) I can't ship the car to the U.S. with a swapped motor, so I have at least two years before I'll even start considering the 20b swap.
5) I'd love to do that, but I don't have the money or time to buy another engine and be swapping them back and forth. I work part-time and all my hobbies are too expensive (snowboarding, drifting, and paintball).
It's not my first car, my first was my FJ80 that I still own (being stored in the States while I'm over here). Then over here I had a 300zx (sold it a few months later), and now I have my 180sx drift/track car and my rx-7 for my daily. Usually I don't really have a tight budget, but when I bought the rx-7 it cost me most of my money, and now this **** storm has happened before I could get my money built back up.
Keep in mind that I'm in Japan though. I can get a running 20b Cosmo for less than that over here...
01-06-16, 01:09 AM
#43
bcrotary.
Join Date: Jul 2010
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It's because you asked for advice, then ignored the best advice from a very senior member/ engine builder here as well as others. Build the engine though, let us know how it goes
01-06-16, 07:51 AM
#44
- Kelan
01-06-16, 08:19 AM
#45
just because the car ran ok when it was sold doesn't mean it wasn't sold as an already ticking timebomb. i see it all the time, people build the cars and know they don't know what they are doing, sell them to an unsuspecting buyer who blows the car up a week later.
i would recommend porting the wastegate on the turbos while its out which will help keep boost down if it was creeping while your eye was off the gauge.
i would recommend porting the wastegate on the turbos while its out which will help keep boost down if it was creeping while your eye was off the gauge.
Last edited by RotaryEvolution; 01-06-16 at 08:25 AM.
01-06-16, 10:02 AM
#46
just because the car ran ok when it was sold doesn't mean it wasn't sold as an already ticking timebomb. i see it all the time, people build the cars and know they don't know what they are doing, sell them to an unsuspecting buyer who blows the car up a week later.
i would recommend porting the wastegate on the turbos while its out which will help keep boost down if it was creeping while your eye was off the gauge.
i would recommend porting the wastegate on the turbos while its out which will help keep boost down if it was creeping while your eye was off the gauge.
01-06-16, 10:30 AM
#47
I regret posting anything on this thread, but I guess if you're in for a penny, you're in for a pound.
Listen Kbug, everyone here wants the best for you and your car. First and foremost, that's where every comment is coming from. We all speak from experience and having "been there, done that" and learning painful and costly lessons. Ok? So let's just all get on the same page. We're not chicks, you can take what we say at face value.
We were also all once in high school and once teenagers that knew more then anyone else (yes, I know, I know - you didn't say that). Everything we thought made perfect sense and no one was going to tell us differently... even if we came asking for advice, what we really wanted was reassurance and a "rah rah" for our already formed plan. However, this is not your fault, the frontal cortex of your teenage brain just isn't formed yet.
Here's what we know about you and your abilities... from your own personal accounts:
These are all HUGE red flags to everyone here, and should be to you as well. But when YOU read that you think: "now it's time to learn how to be a mechanic!" (yes, I know, I know - you didn't say that). Ok great. However, there's a lot more to pulling / rebuilding / installing a motor then any thread can possibly explain. You're going to break bolts, find other things wrong and realize you DON'T have all the tools you need. But most importantly, you still really don't know what caused the engine to go. Even if you rebuild the engine perfectly, managed to get all the check valves and silicone hoses connected correctly and somehow got that Power-FC tuned safely; you may still blow it again if it was, say, a bad injector, fuel filter or fuel pump that caused the engine to go and THAT goes unaddressed. I mean, the shop suggested swapping in a running motor, everyone here suggested swapping in a running motor... but you're going with your plan. Ok.
All that said, if you are deadset on doing your own rebuild, great. It's a really good learning experience. But please take the time to really do it right. Take pictures of everything before you disassemble it so you know how to put it back together. Have hundreds of plastic baggies to save / label bolts and brackets you remove. I personally like using muffin trays. Also, here's links to factory service manuals and wiring diagrams. I hope these help.
1994 Mazda RX7 Workshop Manual (75MB)
1994 Mazda RX7 Wiring Diagram(color) (30MB)
1994 Mazda RX7 Body Electrical Manual (18MB)
1993(-95) Mazda RX7 Service Highlights Manual (27MB)
I want to say "good luck" but deep down I hope you realize what a horrible mistake you are about to make.
Sooo... good luck.
Listen Kbug, everyone here wants the best for you and your car. First and foremost, that's where every comment is coming from. We all speak from experience and having "been there, done that" and learning painful and costly lessons. Ok? So let's just all get on the same page. We're not chicks, you can take what we say at face value.
We were also all once in high school and once teenagers that knew more then anyone else (yes, I know, I know - you didn't say that). Everything we thought made perfect sense and no one was going to tell us differently... even if we came asking for advice, what we really wanted was reassurance and a "rah rah" for our already formed plan. However, this is not your fault, the frontal cortex of your teenage brain just isn't formed yet.
Here's what we know about you and your abilities... from your own personal accounts:
- "I've never been to a school with an automotive class and I'm the only "car person" in my family. I've never pulled an engine or really tore into one for that matter."
- "I've already found plenty of threads and posts on how to remove the engine"
- "I'm assuming a combination of mods on stock ECU and the fact that it's a 1992 took their toll and wore it down."
These are all HUGE red flags to everyone here, and should be to you as well. But when YOU read that you think: "now it's time to learn how to be a mechanic!" (yes, I know, I know - you didn't say that). Ok great. However, there's a lot more to pulling / rebuilding / installing a motor then any thread can possibly explain. You're going to break bolts, find other things wrong and realize you DON'T have all the tools you need. But most importantly, you still really don't know what caused the engine to go. Even if you rebuild the engine perfectly, managed to get all the check valves and silicone hoses connected correctly and somehow got that Power-FC tuned safely; you may still blow it again if it was, say, a bad injector, fuel filter or fuel pump that caused the engine to go and THAT goes unaddressed. I mean, the shop suggested swapping in a running motor, everyone here suggested swapping in a running motor... but you're going with your plan. Ok.
All that said, if you are deadset on doing your own rebuild, great. It's a really good learning experience. But please take the time to really do it right. Take pictures of everything before you disassemble it so you know how to put it back together. Have hundreds of plastic baggies to save / label bolts and brackets you remove. I personally like using muffin trays. Also, here's links to factory service manuals and wiring diagrams. I hope these help.
1994 Mazda RX7 Workshop Manual (75MB)
1994 Mazda RX7 Wiring Diagram(color) (30MB)
1994 Mazda RX7 Body Electrical Manual (18MB)
1993(-95) Mazda RX7 Service Highlights Manual (27MB)
I want to say "good luck" but deep down I hope you realize what a horrible mistake you are about to make.
Sooo... good luck.
Last edited by MattGold; 01-06-16 at 03:19 PM.
01-06-16, 10:33 AM
#48
I'll also assume your tuning abilities are on par with your engine rebuild abilities. Please be careful, there is ZERO room for error on a rotary. Piston engines can be tuned by the sound of detonation, by the time you hear it it a rotary, it's too late.
01-06-16, 10:33 AM
#49
Ban Peak
iTrader: (49)
A catless wide open exhaust could have caused you to creep and blow your engine even though it was a "good, running, clean car" when you got it. A failing fuel pump could have blown your engine, etc.
You're putting yourself in a world of hurt by not heeding advice that has been given.