If you have read my other threads, you will know that I am currently in the process of a rebuild, and if not, then, well... I am currently in the middle of a rebuild! I will try to update this thread at least semi-regularly (as time allows) and post at least a few pictures.

A few months ago (I don't even remember when at this point), my 2006 RX-8 with 100k miles overheated. It was towed to our house, and I pulled the engine. It then sat for 2 or 3 weeks, and I tried to get a Mazda reman; only to find out that they are out of stock, and 2 weeks later, they had raised the price by $1000. "Screw that" I said! "I'll do it myself!" I had read up on the dangers of rebuilding, and was well aware of the potential money pit that it could be, especially if I screw something up, but what better way to learn then to do it myself. Then excited me tried this amusing list of things to get the front E-shaft bolt off:

• Going at it with my dad’s 1300 ft-lb impact for almost an hour straight
• Heating it until bright red then using the above impact
• Almost bending a 36” breaker bar, and bending a few other things in the process
• An 1800 ft-lb Milwaukee electric impact at the local mechanic
• A 1900 ft-lb impact at the local mechanic
• Aforementioned big impact with lots of heat
• The biggest 3/4” ratchet I have ever seen (the thing is ~8 lbs) with a ~8 foot long pole

Yea, it was on there really good. I put it on my dad's big drill press (yup, the whole engine, see the picture), and tried to drill the bolt off. No dice, our cheap drill bits are not good enough to go through the hardened steel of the bolt. So...... what to do?


Renesis on a drill press...


I decided to try something that I had not read about anywhere, probably for a very good reason. I broke out our plasma cutter. Originally, my plan was to cut at a 45 degree angle all the way around, possibly destroying the crank pulley mounting thing, but cutting out a nice clean cone centered around the middle of the bolt. That fell apart real quick. I ended up just hacking away at it until it was just a bath of hot, mushy metal, so I could then pull off chunks until the thing eventually came off. I got the engine apart, and I will update this thread when I get back to our garage to reassess the condition of the parts, but it seems decent upon first glance.

 

Heat it until it melts, can’t be stuck if it’s liquid.

 

How's that? that is the hub that the crank pulleys mount to. sorry for the horrible quality.

 

Is that from your efforts to get it off ?

I feel for you man .... I've had some battles with that nut myself . The latest one .............I gave up on.

 

yup, but it is off, and that is all that matters... I dont have pictures of the E-shaft (actually not that bad) at the moment, but i will get them.

 

Yeah, I took the engine to a custom auto shop for removal of that bolt during my rebuild. Took them about 20 min of torching and HIGH impact driver.

Glad you got it off. The success of your rebuild will depend on the accumulation of systematic small victories.

 

I did take it to our local shop, but their impact could "only" do 1900 ft-lbs... a bit of heat did not help at all... this one took a grinder, reciprocating saw, and plasma cutter

 

That's insane... I've never had one on that tight before. I mean, you're rebuilding it anyways so replacing it isn't a big deal at this point.

 

yea, I cannot believe I had to resort to such drastic measures.

 

Desperate times call for desperate measures I suppose. At least its apart.

 

Well I'm intrigued to say the least keep us posted!

 

a quick update... no more pictures, but hopefully I will have some soon...


I really should have expected this given that my engine had 100k miles on it, but one of my rotor housings was basically unusable (major chrome flake, especially up near the oil injector holes; also pretty bad chatter near the bottom, also had 2 parallel lines running all the way around the housing), but the other was in good condition. I was going to go with Adam at rotaryengine.com (I have seen this company referred to as a million different things... REC, Rx7 specialties, rotaryengine.com etc.) for resurfacing (going the cheap route... I know it is not as good as new, like I have said before, the car has rust problems. 30k from this rebuild would be great), but I needed another housing anyways, so he managed to sell me 2 resurfaced housings in "great" condition (it really was not hard. He basically mentioned it and I said sure...) Estimated delivery is Friday, so stay tuned for more...

I got myself a Harbor Freight blast cabinet, and some glass beads, and walnut shells. Glass beads to strip bare metal parts (pulleys etc.), and walnut shells to clean up irons and front cover (the cabinet refuses to pick up the walnut shells at all, and is very finicky with the glass beads, any tips?). Got a used e-shaft off ebay that looks to be in pretty decent condition, for roughly half what Atkins wants for a new one. As much as I think I should, I don't think I am going to replace the pilot bearing, just because of the tools I would need and the pain in the butt to do it...

 

Regarding the pilot bearing, I would replace if it's not good shape. It will be well worth the effort while you have it out. I just replaced one. As far as the tools, I bought all the tools and tried every trick listed to get it out. In the end, I just had to grind it our with a drill and stone bit. You just have to be careful. Good luck.

 

how do I tell if it is in good shape (no I did not search yet... it is late and I will do that tomorrow)

 

Mazda makes a tool for removing the pilot bearing. Takes seconds to remove the pilot bearing with the tool. Best $120 I ever spent on a specialty tool.

As for the pilot bearing, when they fail, the needle bearings will fall out of the race and you may see that some or all of them are missing. Once you remove the grease from the needles, you can check for wear in the needle bearings if you'd like. Personally, it's a part that gets replaced no matter what, so I don't bother with checking them for wear. I install a new pilot bearing and seal with every clutch or engine replacement.

 

stop tempting me... any special tools required to install the new one? What happens when they fail (not to the bearing, but to other stuff)?

Here are some pics of my good rotor housing. It actually seems pretty decent, just the edge wear...









and the bad housing...

 

That is what a munted housing looks like ...yep ! Please don't try re-use either of those housings.

 

Isn't the pilot bearing tool just a slide hammer?

 

Don't worry, I am not reusing either housing. Maybe the "good" one will become a table ornament...

I have been procrastinating doing more than a quick search regarding the pilot bearing. My "new" e-shaft is supposed to come in today, so I will take a look at it and maybe post a picture, if I get to that...

 

It is a slide hammer with a threaded end to accommodate a special bit with fingers designed to grab the pilot hearing's race. It does a great job as it fits perfectly and is specifically designed for Mazda rotary engine pilot bearing removal. I'll post a picture of it after work tonight.

 

getting lots of packages... I got a new fan shroud for a new radiator, it is a Flex-a-Lite 410 I think... Quality is amazing, just feels so solid compared to OEM shroud... The used e-shaft I got has tons of rust/scratches on it, rendering it totally unusable, returning that, see pictures:






I got my rotor housing from Adam at RX7 specialties, and they look good. I emphasize good. There does look to be quite a bit of wear, and some minor flaking around the edges... whatever, I have to use them, they are much better then what I had. I will try to post pictures of those later.

I blasted my rotors with walnut shells to clean the carbon; it worked great, but I will never do it again because the rotors were totally filled with walnut shells when I finished (I suppose I should have expected that...). yes, I did manage to get them all out... no, it was not fun.

Got rotor and main bearing tools from Pineapple racing. Took a while to get here, but worth it. very impressed with the quality.

 

AMD,

Fwiw...

- As a cleaning alternative... I cleaned all my reused parts for rebuild by soaking them in Berryman Chem-dip Carburetor Parts Cleaner overnight. Then used a wire wheel drill attachment and assorted wire brushes. The first pic of the rotors was taken after soaking... w/ one wire brushed, and the other not yet. The impact of the solvent on the carbon build up c/b seen.

- Also posting pics of my old vs new (used & refurbished) housings from Goopy Performance for comparison.

All the best.
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yea, my edge wear on the new housings is a bit worse than that, but whatever... I would be happy if the motor lasts 30k miles; the car has rust issues, so it probably will die before the engine...

 

Understood...heck mine may only last that long... . So, while apart... I recommend you do the best rebuild you can ...given your budget and expertise. #Noregrets.

 

I am doing the best I can, but I am trying very, very hard to make it a "budget rebuild" while getting experience and having fun... I am going to really try to not do my clutch, as it was already replaced with an Exedy OEM replacement (I dunno when), but a friend who is rebuilding his Subaru, who said he does not know that much about clutches, said it looks like I have maybe another 35-40k left. yes, I have more research to do...