Likelihood of rx8 breaking down for no reason.
10-21-2020, 02:34 AM
#1
Likelihood of rx8 breaking down for no reason.
So I've been obsessed with rx8 for the past 2 years and am looking at one on the market right now with my dream colour way black exterior white interior as my first car. It has 95,000 km/ 60,000 miles on it. I want to buy it and i am willing to take care of and premix etc my only worry about owning one is the likely hood of one just blowing an apex seal or engine breaking down and needing a rebuild out of no where. Of course if only buy the car if i check it out with my mechanic to see if its running properly as well as good compression test results. What do you guys think?
https://vancouver.craigslist.org/rds/cto/d/surrey-2007-mazda-rx8/7204304759.html
https://vancouver.craigslist.org/rds/cto/d/surrey-2007-mazda-rx8/7204304759.html
10-21-2020, 04:56 AM
#2
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"This IP has been automatically blocked.If you have questions, please email: blocks-b1602642654100405@craigslist.org"
Anyway. Use a proper rotary compression tester. Take the smallest of the 6 compression values and see where you're at. This is my take on it, if I were to buy another RX8 right now.
5 bar (70 psi) or less: Do not buy a car with this compression figure for more than $500-$1000. This is a rolling shell ( = no engine). Until you pull apart the engine, you have no idea if the engine is even worth rebuilding.
5.5 bar (80 psi) or less: Do not buy a car with this compression figure unless you want to rebuild it right away.
5.5-6.0 bar (80-87 psi): Half decent half bad. Might be a compromise to buy the car for cheap, drive(and fall in love with) it and when the time comes, rebuild it.
6.0-6.5 bar(87-95 psi): Reasonable wear and tear to good condition zone. Decently looked after cars should be in this area. From a wear point of view, this engine has about a third to a half of its life remaining.
6.5 bar (95 psi) or more: It's worth buying, by any means. It’s a good figure that shall last for a few more years, if you take care of it.
7 bar (101 psi) or more: Excellent result! This car/engine is totally worth buying, as long as it's not eating coolant or excessive oil.
Past this, its an old car. 14yo by now, so do expect some electrical issues, tired fuel pump if its never been replaced, worn starter, maybe a leaking/stuck injector, the usual stuff on a car of this age. If the compression is good, don't worry about it dropping an apex seal in the middle of the road.
Anyway. Use a proper rotary compression tester. Take the smallest of the 6 compression values and see where you're at. This is my take on it, if I were to buy another RX8 right now.
5 bar (70 psi) or less: Do not buy a car with this compression figure for more than $500-$1000. This is a rolling shell ( = no engine). Until you pull apart the engine, you have no idea if the engine is even worth rebuilding.
5.5 bar (80 psi) or less: Do not buy a car with this compression figure unless you want to rebuild it right away.
5.5-6.0 bar (80-87 psi): Half decent half bad. Might be a compromise to buy the car for cheap, drive(and fall in love with) it and when the time comes, rebuild it.
6.0-6.5 bar(87-95 psi): Reasonable wear and tear to good condition zone. Decently looked after cars should be in this area. From a wear point of view, this engine has about a third to a half of its life remaining.
6.5 bar (95 psi) or more: It's worth buying, by any means. It’s a good figure that shall last for a few more years, if you take care of it.
7 bar (101 psi) or more: Excellent result! This car/engine is totally worth buying, as long as it's not eating coolant or excessive oil.
Past this, its an old car. 14yo by now, so do expect some electrical issues, tired fuel pump if its never been replaced, worn starter, maybe a leaking/stuck injector, the usual stuff on a car of this age. If the compression is good, don't worry about it dropping an apex seal in the middle of the road.
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Phillip Le (10-23-2020)
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10-21-2020, 08:01 AM
#5
Rx8help.com, "New and Potential Owners" section should give you a primer. Nothing breaks for no reason, but if you're looking for assurances, quirky sports cars aren't the best place to look 
Compression test is key. These cars are getting old. 95k km is not bad, if well taken care of. This one looks clean.
Compression test is key. These cars are getting old. 95k km is not bad, if well taken care of. This one looks clean.
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Phillip Le (10-23-2020)
10-21-2020, 08:18 AM
#6
You gonna eat that?
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Phillip Le (10-23-2020)
10-21-2020, 09:06 AM
#7
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Black with white interior?
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Phillip Le (10-23-2020)
10-21-2020, 09:19 AM
#8
You gonna eat that?
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Phillip Le (10-23-2020)
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10-21-2020, 12:03 PM
#10
FULLY SEMI AUTOMATIC
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the shinkas had a whiteish interior (parchment iirc) but other countries actually got a white interior
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Phillip Le (10-23-2020)
10-21-2020, 12:41 PM
#11
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Tbh apex seals do not randomly explode by any means, I think people are kind of mislead a bit since these were older issues with boosted engines. Generally rx8 engines just lose compression and begin having issues hot starting>idling>cold starting.
No matter what plan on rebuilding your engine at 80-90k miles. From what I have seen from the three engines I pulled apart, it'd be better to rebuild earlier instead of running the compression/coolant jackets dry at 120k miles to see what happens like I did.
When you do your rebuild do your research and try to learn how porting intake/exhaust actually affects the engine.
No matter what plan on rebuilding your engine at 80-90k miles. From what I have seen from the three engines I pulled apart, it'd be better to rebuild earlier instead of running the compression/coolant jackets dry at 120k miles to see what happens like I did.
When you do your rebuild do your research and try to learn how porting intake/exhaust actually affects the engine.
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Phillip Le (10-23-2020)
10-21-2020, 01:25 PM
#12
I don't know that a mileage-based rebuild recommendation makes sense. Some engines do 20k miles, others do 200k miles.
If you do end up getting one, test compression occasionally and start planning a rebuild when it crosses Mazda's replacement threshold. Also the engines don't die by themselves. Poor ignition and poor catalytic converter health can kill them. Keeping an eye on those things removes the main dangers. There are solutions. As long as you're going into this with your emotions in check and eyes open, and a rebuild can fit in your budget if necessary, you're in a good place.
If you do end up getting one, test compression occasionally and start planning a rebuild when it crosses Mazda's replacement threshold. Also the engines don't die by themselves. Poor ignition and poor catalytic converter health can kill them. Keeping an eye on those things removes the main dangers. There are solutions. As long as you're going into this with your emotions in check and eyes open, and a rebuild can fit in your budget if necessary, you're in a good place.
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Phillip Le (10-23-2020)
10-21-2020, 02:26 PM
#13
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Tbh apex seals do not randomly explode by any means, I think people are kind of mislead a bit since these were older issues with boosted engines. Generally rx8 engines just lose compression and begin having issues hot starting>idling>cold starting.
No matter what plan on rebuilding your engine at 80-90k miles. From what I have seen from the three engines I pulled apart, it'd be better to rebuild earlier instead of running the compression/coolant jackets dry at 120k miles to see what happens like I did.
When you do your rebuild do your research and try to learn how porting intake/exhaust actually affects the engine.
No matter what plan on rebuilding your engine at 80-90k miles. From what I have seen from the three engines I pulled apart, it'd be better to rebuild earlier instead of running the compression/coolant jackets dry at 120k miles to see what happens like I did.
When you do your rebuild do your research and try to learn how porting intake/exhaust actually affects the engine.
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Phillip Le (10-23-2020)
10-22-2020, 02:17 AM
#14
Registered
Personally now I'm planning out how to turbo my rebuilt ren and start on a rew setup, which will inevitably need a shop to custom machine parts on the rew engine build. Looking at these guys right now, but I want to make an actual write up on what I want. Their youtube content is nice to see also.
https://www.rotaryengine.com/
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Phillip Le (10-23-2020)
10-22-2020, 09:30 AM
#15
You gonna eat that?
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I've noticed people tend to post when bad things happen, not so much when everything's good.
There are still lots of people successfully rebuilding engines professionally.
If they repeatedly had bad results they'd probably wouldn't be in business still.
You live on an island, right?
Your options are limited by expense.
If someone plans on spending money on a 'replacement', are they able/capable of pulling and reinstalling an engine?
If you get a remanufactured engine you need to send the old core back unless you can afford to absorb the $1K charge.
If you buy a salvage engine you're rolling the dice, getting compression tested proven engines isn't easy.
That's one factor that figures into getting a rebuild, paying for the labor to pull it, rebuild, and reinstall.
People need to be sure to weigh all their options and do their research.
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Phillip Le (10-23-2020)
10-22-2020, 09:47 AM
#16
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Idk how many is "too many".
I've noticed people tend to post when bad things happen, not so much when everything's good.
There are still lots of people successfully rebuilding engines professionally.
If they repeatedly had bad results they'd probably wouldn't be in business still.
You live on an island, right?
Your options are limited by expense.
If someone plans on spending money on a 'replacement', are they able/capable of pulling and reinstalling an engine?
If you get a remanufactured engine you need to send the old core back unless you can afford to absorb the $1K charge.
If you buy a salvage engine you're rolling the dice, getting compression tested proven engines isn't easy.
That's one factor that figures into getting a rebuild, paying for the labor to pull it, rebuild, and reinstall.
People need to be sure to weigh all their options and do their research.
I've noticed people tend to post when bad things happen, not so much when everything's good.
There are still lots of people successfully rebuilding engines professionally.
If they repeatedly had bad results they'd probably wouldn't be in business still.
You live on an island, right?
Your options are limited by expense.
If someone plans on spending money on a 'replacement', are they able/capable of pulling and reinstalling an engine?
If you get a remanufactured engine you need to send the old core back unless you can afford to absorb the $1K charge.
If you buy a salvage engine you're rolling the dice, getting compression tested proven engines isn't easy.
That's one factor that figures into getting a rebuild, paying for the labor to pull it, rebuild, and reinstall.
People need to be sure to weigh all their options and do their research.
The following users liked this post:
Phillip Le (10-23-2020)
10-23-2020, 12:28 PM
#17
Thank you to everyone that replied! It has given me a lot of insight and information and was very helpful. This community is awesome. Some good news 2 more Rx8's have popped up on the market at $8000 and $5500 CAD and will be checking them out and getting them compression tested. Thank you again for all your help.
10-23-2020, 05:35 PM
#18
Registered
Just know that compression varies with engine speed. Ideally you want numbers at 250 rpm. If you get a compression tester from https://www.rotarycompressiontester.com/ it will have the crank speed value and a corrected value at 250rpm which is nice to see. Compression at 250rpm should range between 85-120psi. You really want 90+psi if possible.
I've seen false compression videos on youtube from some import companies showing absurd numbers like 180psi at 130rpm.....ummm.....no in this case something is wrong. Just be careful when it does come time to get another engine or rebuild.
I've seen false compression videos on youtube from some import companies showing absurd numbers like 180psi at 130rpm.....ummm.....no in this case something is wrong. Just be careful when it does come time to get another engine or rebuild.
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