1 2
old_
old_ Reader
4/28/15 12:27 p.m.

A local dealer has a 04 RX8 with a popped engine. The car is in pretty good shape with only 50kmi. What kind of $$$ would I be looking at for a rebuild assuming the rotors and housings are usable?

I found these guys after a quick search: http://www.rotaryresurrection.com/ looks like $1600 + ~$250 shipping both ways. Thoughts?

yes I know, LSX swap. that's not really feasible for my situation.

Toyman01
Toyman01 GRM+ Memberand MegaDork
4/28/15 12:41 p.m.
old_ wrote: yes I know, LSX swap. that's not really feasible for my situation.

Well, you already sucked all the fun out of this one.

BoxheadTim
BoxheadTim GRM+ Memberand UltimaDork
4/28/15 12:49 p.m.

In reply to old_:

He mentioned that the 1600 bucks are "base", so I'd expect that the price may go up considerably depending on what's damage (as in if it needs a new housing or rotor).

Mazda reman engines aren't that expensive (IIRC around or below $4k) and I'd guess they come with a warranty. That may be another option.

Knurled
Knurled UltimaDork
4/28/15 12:53 p.m.
old_ wrote: A local dealer has a 04 RX8 with a popped engine. The car is in pretty good shape with only 50kmi. What kind of $$$ would I be looking at for a rebuild assuming the rotors and housings are usable?

If you wait until pop before rebuilding, you're more or less guaranteed to have eaten at least one rotor and rotor housing. Side housings are usually okay but I've seen one munched by FOD before.

From what I have heard about the Mazda reman plant, or rather the company that they sublet it out to, you're far better off doing it yourself. They didn't bother to differentiate between rotor weights or flywheel weights, so you'd get a two different weight or two different compression rotors, or the wrong counterweight, and seal tolerances in the "eh, it went together" range.

bgkast
bgkast GRM+ Memberand UltraDork
4/28/15 12:55 p.m.

Did it pop, or just loose compression gradually? I would plan on $3k for the rebuild.

WonkoTheSane
WonkoTheSane GRM+ Memberand Reader
4/28/15 1:02 p.m.

If you don't do it yourself (it's the easiest engine build you could ever do), then I'd say that Kevin RotaryResurrection had a really good reputation when I used to follow the rx7club a lot closer. I'd let him rebuild my engine if I didn't want to tackle it..

BoxheadTim
BoxheadTim GRM+ Memberand UltimaDork
4/28/15 1:04 p.m.

Also, do you know for sure the engine is blown? I've heard a bunch of stories about RX8s "regaining" compression after fitting new coils, if you get my drift...

Hungary Bill
Hungary Bill GRM+ Memberand SuperDork
4/28/15 1:11 p.m.

I have the DIY-RE box set you can borrow. It pertains to the 13B, but the information translates.

Atkins Rotary has the rebuild kit you'd need: https://www.atkinsrotary.com/index.php?pag=5

I used both with great results on my old RX-7. But I did have to make one engine from two (bought the second for $50 blown) and got lucky when the weights matched up.

amg_rx7
amg_rx7 SuperDork
4/28/15 3:19 p.m.

Kevin at Rotary Resurrection is pretty reliable for a budget rebuild.

Alternatives
- find your favorite local rotary shop and have it rebuilt locally. Closest that I know of is http://www.banzai-racing.com
- check in with Ray Crowe at Malloy Mazda on the state of RX8 engine rebuilds. He gets the cream of the crop engines from the rebuilder since he sells so many of them. (703) 490-5296

JtspellS
JtspellS SuperDork
4/28/15 3:35 p.m.

Plan at absolute worst case $4k, and +1 with Atkins kits, banzi-racing is quite reputable as well.

Knurled
Knurled MegaDork
4/28/15 4:30 p.m.
BoxheadTim wrote: Also, do you know for sure the engine is blown? I've heard a bunch of stories about RX8s "regaining" compression after fitting new coils, if you get my drift...

Stories hell, there was a TSB that an engine with low compression should get new coils before sticking a fork in the engine. And I have heard from a (rotary knowledgeable) guy that, by some sorcery, compression would come up 20-50% after installing the updated coils and running it a bit.

That's the point where I go bibbledy and say, berk it, I don't get exactly how/why it does that, but it does that, so I'll just shut up and do it. And I've been playing with rotaries for the best part of 17 years...

Trackmouse
Trackmouse Reader
4/28/15 4:58 p.m.

Not sure what coast you live on, but we have some guys here in the PNW that will teach you to rebuild your for free... That's as far as I'll go info wise.

racerdave600
racerdave600 SuperDork
4/28/15 5:29 p.m.

A buddy bought a RX8 with a supposedly blown motor. Turned out to be a weak battery. Bad part here is that the dealer is the one that declared it blown. He got essentially a perfect RX8 for $500.

clutchsmoke
clutchsmoke Dork
4/28/15 6:04 p.m.

Scoop it up. Rotary resurrection had a good reputation when I was all over rx7club. I would try out some coils first once you get it home. Should take about half an hour to install.

wvumtnbkr
wvumtnbkr GRM+ Memberand SuperDork
4/28/15 6:19 p.m.

Check the cat too. I had bad coils lead to a bad cat. Once I replaced coils, it still had low compression it seemed.

The clogged cat caused such a restriction that the airflow was insufficient to allow complete volume filling and therefore low compression.

Weird but true!

old_
old_ Reader
4/28/15 6:26 p.m.

Thanks for the info guys. It's at a (new) mazda dealer and I am wondering why they don't just fix and sell it (no rotary experience?). I've not talked to them to get any specifics but I do know they are asking $2k. I will update when I find out more

amg_rx7
amg_rx7 SuperDork
4/28/15 6:35 p.m.
old_ wrote: Thanks for the info guys. It's at a (new) mazda dealer and I am wondering why they don't just fix and sell it (no rotary experience?). I've not talked to them to get any specifics but I do know they are asking $2k. I will update when I find out more

Probably b/c they don't know how to fix it and talked the owner into a new car...

BoxheadTim
BoxheadTim GRM+ Memberand UltimaDork
4/28/15 6:47 p.m.

I'm guessing that it wouldn't work out for them financially - a decent 04 is worth what? $6k? $7k?

They'd have to provide some sort of warranty and also make some money. I think there's just not enough profit in it for them.

Ranger50
Ranger50 PowerDork
4/28/15 7:26 p.m.
BoxheadTim wrote: I'm guessing that it wouldn't work out for them financially - a decent 04 is worth what? $6k? $7k? They'd have to provide some sort of warranty and also make some money. I think there's just not enough profit in it for them.

^^This^^

Even if parts was generous and sold a reman for cost plus 5% instead of cost plus 40% to sales and service cut the labor rate in half from $100/hr to 50.. it still would be a $3500 repair easily. Add in what sales "gave" the customer at trade-in, you have the bare minimum of what they would sell it for minus all the other stuff they would fix to have be sellable to anyone, which is easily going to be a grand, if not more, much more with a properly done used car inspection. You just aren't going to see any profit in 6-8k cars, unless you are wholesaling as-is.

BrokenYugo
BrokenYugo UltimaDork
4/28/15 9:02 p.m.

In reply to Knurled:

I would guess the sorcery at hand is a failing coil giving weak spark and poor combustion increasing carbon buildup, seals get sticky and it loses compression. Get it running again with a functional ignition system and an Italian tuneup fixes the problem.

Knurled
Knurled MegaDork
4/28/15 9:09 p.m.

In reply to Kenny_McCormic:

Yeah, maybe, But the compression supposedly comes up just in a few minutes of idling. So maybe it's an issue of unburned fuel coating the chamber walls, because the side exhaust ports don't allow that to be swept right out with every cycle, and high fuel/low oil hurts compression since the chrome needs to be "charged" with oil for the engine to have decent compression?

Theory this, theory that, good spark is important for rotary, and maybe is super duper important for a rotary with side exhaust ports so it can't flush itself of its own waste products.

OTOH I remember having to change spark plugs and fuel filter every 3,000 mi or you really noticed it when driving. Also, current engine makes more power the more oil I feed it, despite what the Internet says, to the point where I am premixing Lucas synthetic oil 60:1 mostly because any richer and the oil smoke is visible when cold and I think that is uncouth. But it probably would get better compression/more power if I mixed even more oil into the fuel.

Kenny_McCormic
Kenny_McCormic PowerDork
4/29/15 2:41 a.m.

Huh, that is weird. The oil thing makes sense though, 2 stroke engines are similar in that regard, more oil means better ring seal and better heat transfer from the piston to the cylinder, so you can run leaner and/or with more timing advance.

Ranger50
Ranger50 PowerDork
4/29/15 7:06 a.m.

Damn, some of these things are near challenge money with "blown up motors". Most are tragically autos though....

84FSP
84FSP Reader
4/29/15 7:21 a.m.

Looking forward to how this pans out. These are cheap enough and check enough performance boxes for me while having a realistic backseat (for kiddos).

Cotton
Cotton UberDork
4/29/15 8:41 a.m.
Knurled wrote: In reply to Kenny_McCormic: OTOH I remember having to change spark plugs and fuel filter every 3,000 mi or you really noticed it when driving. Also, current engine makes more power the more oil I feed it, despite what the Internet says, to the point where I am premixing Lucas synthetic oil 60:1 mostly because any richer and the oil smoke is visible when cold and I think that is uncouth. But it probably would get better compression/more power if I mixed even more oil into the fuel.

Damn! I only run 50:1 synthetic in my 2 stroke dirtbike.

1 2
Our Preferred Partners
1BDnTTCmAeVLPUjbg0cMJuni7oScpqhPbuLkGZSTObpvcXd7huLcLPe90xZuKSbH