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Apex Seals
Ok guys, so I realise that I need to replace my apex seals in my 07 Rx8. Now from reading other posts and what not, I have a few questions. Do I need to rebuild my engine completely if I just replace the seals on my rotors? or can I just replace the seals, put my motor back together and move on with my life? also, after either solutions what do I need to do to put my motor back into tip top condition (tune the engine, add upgrades, rub a rabbits foot, etc..)? Thanks, Mike |
Why do you need to replace your apex seals?
What about the side seals and all the other seals in the engine :) There is much more to a rebuild than replacing the apex seals........... |
Opening the engine at all, for any reason is an engine rebuild. Reusing any existing seals is a pretty bad idea, so any engine rebuild will mean new seals for everything. The irons should get relapped as well to make sure they are up to spec. That's a minimum rebuild and still likely to have problems from not replacing the housings.
See the modding thread in my sig under the power section for more options and stuff to consider on an engine rebuild. If you are within 8yrs and 100k of purchase, then you are still in the factory engine warranty. Otherwise, your cheapest option for the engine is going to be Mazmart. Technically you could go through the dealer, but their quality is often subpar anyway. Mazmart is located in Georgia (so you would save tons on shipping), a forum vendor here, and has top notch quality engine rebuilds. They can rebuild yours or sell you a rebuilt one with cash back for getting your old engine. I'm sure they can even do the swap for you if you drive over to them. |
You're right on that one, I'm just assuming its about high time to replace the apex seals 123k miles, hard cold starts and a noticable reduction in power (get up and go). So thats why I was asking if I needed to completely rebuild the engine or just replace the a-seals.
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Okay, you need to learn a bit more before you dive into this. Yes, you likely have some loss of compression, but you should really get a compression test from a Mazda dealer (they have the rotary compression testers) though I'd expect Mazmart has one too (unsure if they actually do though). Find out for sure if you do have failing compression. You might not actually.
Hard cold starts usually isn't the sign of failing compression, usually it's hard warm starts with cold starts being better, among other things. It could also be a failing battery, failing starter, or failing ignition, or leaking coolant into the housings while it's shut down. "Power loss" can be a TON of different things, including: Coil failure, Plug failure, Plug wire failure, Cat failure, Compression loss, Dirty MAF, O2 sensor failure, Fuel Filter clogged, Fuel pump failure, Battery terminals corroded, Air filter clogged, Fuel injectors clogged, Fuel injectors leaking, E-shaft sensor fouled, Fuel trims not set/reset, Incorrect MAF scaling, Carbon Buildup, SSV failure, Coolant seal failure... Identify your problem FIRST, then work on a solution. Don't assume and start pursuing something that you are just guessing at. |
Ok so here is the problem. Besides the hard cold starts, while driving, after going from neutral to first, it feels like the engine sounds louder and more throaty, it feels like it is struggling to gain RPMs from 1st all the way until I shift into 4th (6 speed). It drives like I'm pulling something extremely heavy. Enough info for a close guess to the culprit?
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Not really. :)
It could be a clogged cat (throttles the exhaust flow from higher load), which is usually from ignition failure, which could also be doing that, as well as causing the hard starts. All it would take it some black current to weaken the battery while the car sits vs having a better charge while it's still hot to contribute to the harder starts when cold vs warm. |
brand new batt. (2 weeks old), so what would I have to do to find the exact cause?
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How old is your ignition? Miles and years.
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it's an 07' and I doubt that the ignition has been replaced on it since, but the car has around 123,000 miles
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There you go... Coils last on average 30,000 miles, plugs usually fail by then, or if they are still good, the coils failing kills them quick. The wires degrade over time and heat.
They aren't burning the air and fuel mixture completely, so the air and fuel are getting dumped into the header, where it's igniting under the exhaust heat from what is burning, and that is blowtorching your cat to slag, clogging it which then is throttling your engine power. Continuing to drive like this is probably also going to damage the O2 sensors and engine, if they haven't already suffered damage by now. The cat's localized heating is stressing the engine and the sensors, and will damage them soon if they aren't already. Continuing to drive on it past this point opens up the possibility of the overheating cat lighting your car on fire... It still might be something else, but if you have no clue when the ignition was last replaced it's clearly time you do so. It is possible to get all the ignition parts needed for around $182 total, and replacement is simple, an hour tops for you if you don't know your way around cars. Otherwise as fast as 20 minutes. Dealers will charge you $800 or more for the parts and labor. https://www.rx8club.com/rx-8-discuss...t-here-202454/ Importance of Ignition Health: ************************ READ THIS!!!! ************************ One of the most often overlooked or ignored parts of RX-8 ownership is the health of the ignition system. This includes the ignition coils, spark plug wires, and spark plugs. They fail. Often. So often as to be critical parts of regular maintenance. Before I detail why, check out the first post of this thread here: https://www.rx8club.com/series-i-trouble-shooting-95/impact-old-coils-wires-plugs-234383/ (owner's post here: https://www.rx8club.com/showpost.php...&postcount=189) The owner's power dropped from 199whp to 172whp JUST from failing ignition. That's a 13.5% power loss! Do I have your attention now? Good. Mazda officially lists the plug wires and plugs as part of regular maintenance, but not the coils. Many dealers STILL don't know how easily the coils can fail. And they fail about the same time as the wires and plugs, which is about every 30,000 miles. Some can last longer, some shorter, and it's more related to your total RPMs than it is to your mileage. Highway cruising is easier on the coils than spending a day pounding around a race track. When coils fail, they don't suddenly shut off. They start producing weaker pulses scattered among strong ones. The rate of weak pulses slowly increases and pulses start getting dropped entirely, which is where misfires start. All of this means that you aren't burning all the fuel and aren't using all the air that the engine pulled in for that combustion, and it unburnt fuel and air gets dumped into the exhaust, where it happily ignites with the presence of plenty of heat. This saturates the cat in both fuel and heat, and will rapidly kill the cat (A $1,300 USD replacement). Continuing to drive on a failing cat will add other problems such as engine damage and vehicle fires. I am not exaggerating, this can happen with just a single cat failure! Plug fouling and wire failure is largely the same result, since all 3 pieces are needed for a complete spark. Foul the plug and it doesn't matter if the coil and wire are good. Break down the wire and it doesn't matter if the coil and plug are good. Symptoms of ignition failure include: Power Loss, mileage drop, unstable idle, bad idle, inability to idle, shaking at idle, unstable high rpm, misfiring, flashing CEL, coughing engine, glowing cat, flooding, inability to start, inability to pass an emissions sniffer test, and just about anything you can think of where a weak or missing spark causes problems. And if one fails, it will cascade to the other trio on the same rotor. A plug that can't fire will start fouling the other. A coil that can't fire a plug starts wearing out rapidly (if you want to test this, just unplug a wire from a plug and run the engine for a while. The coil will rapidly fail. Not unique to rotary engines) Why do coils fail so easily? This is largely because Mazda opted for cheap coils because of RX-7 owner complaints about how expensive their coils were. The RX-7 coils lasted much longer though. So Mazda went cheap, and so we have to replace regularly. And you can't compare to piston engine coils. A piston engine with the same setup of 1 coil for 1 plug has an average RPM of about 2,500rpm and the coil is firing every other revolution, so the coil is firing about 1,250 pulses per minute. Our rotary has an average RPM of more like 4,000rpm, and each coil fires every revolution, so about 4,000 pulses per minute. That's a bit over 3 times more. Even a piston max RPM of about 6,000rpm vs our 9,000rpm makes the difference 3,000 pulses per minute vs 9,000 pulses per minute, or 3 times as fast. If our coils would last about 3 times longer, you are talking an average of 90,000 miles. So keep your ignition healthy! |
So what are all the parts that I'm going to need and what will I be looking for? are there any guides (hopefully with pictures) on how to do it?
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4 coils, 2 trailing plugs, 2 leading plugs, 4 plug wires. If you are really concerned about buying the right stuff, contact Mazmart. Otherwise the parts are sold by pretty much every major auto parts chain, online and retail, and many of the vendors here.
DIYs are here on the site. Do a Google search with: site:rx8club.com DIY coil replacement and site:rx8club.com DIY plug replacement |
So after replacing the coils and plugs what else is there to do?
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Then check the cat. Since you are out of all warranties, just pull the cat and see if the honeycomb is missing or damaged. Best way to do this is to buy new exhaust bolts from an autoparts stores (not normal hardware stores unless you get stainless steel bolts, due to the heat and rust), take the car to a corner small garage, pay them $20-$40 to put it on a lift and remove the old rusted cat hardware and put in the new hardware. Or pay them more to actually remove the cat and check.
You haven't mentioned a CEL, but then most of the time a CEL isn't thrown for a clogged cat. Plenty of dealers and shops just want to trust the ODB2 output, but that simply doesn't work too often for our car. If you replace the cat ($1,300, a used one on here for cheaper, some aftermarket ones might work long enough if they are metallic substrate, or if you don't have emissions concerns knock out the cat element or put in a midpipe) and the ignition and are still having trouble, get a compression test. |
Thank you so much for this! I'm still a noob on my rx8 but im eager to learn all I can
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BTW what is a CEL?
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Have you ever heard of Google?
You must have, because you found your way to this forum in order to be spoonfed information. How about you read some posts, and find the answers to all your questions for a couple of minutes. BC. |
ok the CEL is not on
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apex seals
I have an 06 that does not start if left alone for more then 2 days. After reading online I am assuming the apex seals are shot. Lucky for me my 8 years is up 11/14. Dealer is doing a compression check later this week. Seams like they all want to just swap the little engine out for a Mazda rebuilt. Makes sense?
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Nope.
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Originally Posted by johnbolen
(Post 4609391)
I am assuming
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Originally Posted by johnbolen
(Post 4609391)
I have an 06 that does not start if left alone for more then 2 days. After reading online I am assuming the apex seals are shot. Lucky for me my 8 years is up 11/14. Dealer is doing a compression check later this week. Seams like they all want to just swap the little engine out for a Mazda rebuilt. Makes sense?
Originally Posted by 9krpmrx8
(Post 4609394)
Nope.
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Originally Posted by nycgps
(Post 4609550)
hope u check it at Wayne Mazda
why not |
The part where you assume the apex seals are damaged because your car does not start after two days.
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