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My engine rebuild.

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Old 04-19-2010 | 11:01 AM
  #51  
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Mating surfaces on irons and seal grooves on rotor housings arent clean enough.

Also closely examine where the lower spark plug holes meet the chrome on the inside, for swelling and cracks. You see in your first pics that thick stripe of carbon across the housing? That is where the housing is usually cracked or swollen around the plug hole, and is lifting the apex seal up like a speed bump. IT will also wear into a new seal if you do not grind down the crack or swollen part gently.

If you sanded that rotor to make it shiny and silver, then you made a little mistake. The stock rotors are zinc coated to give them that shiny yellowish brown appearance. This coating keeps them from surface rusting and also makes the surface smoother. When you take the yellow coating off and wind up with a bare metal shiny silver, you're down to the steel, which will rust. It can also build up carbon more than the stock coated rotor. For this reason I media blast rotors with walnut shell, which blows carbon right off the rotor but doesnt hurt the coating at all.
Old 04-19-2010 | 11:16 AM
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Ok, maybe I will not be rebuilding my rotary
Old 04-19-2010 | 11:25 AM
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Thanks for the reply RR... I was awaiting your reply I didn't want to bother you with a PM I figured enough traffic on this thread would get you.

What do you think about the groove in the first housing, is that reusable?



We used a scotch brite pad a concentrated parts degreaser and wire brush for the rotors.

If needed I can send it off to mazdatrix to get the rotors coated again. But we weren't rough or violent with it.

As for the irons and the housing we haven't even begun to clean them up yet. we were planning on a light hand lapping to get them useable.
Old 04-19-2010 | 11:56 AM
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Originally Posted by shadycrew31
Thanks for the reply RR... I was awaiting your reply I didn't want to bother you with a PM I figured enough traffic on this thread would get you.

What do you think about the groove in the first housing, is that reusable?
Cant tell you until you clean the carbon off and take close up pics of the leading plug hole and any other areas of question.

We used a scotch brite pad a concentrated parts degreaser and wire brush for the rotors.

If needed I can send it off to mazdatrix to get the rotors coated again. But we weren't rough or violent with it.
It will be fine for a rebuild, but for future reference that is not really the accepted "right" way to do it. Usually a wire brush mounted onto a drill is all you need, and won't hurt the coating if you don't push too hard.

As for the irons and the housing we haven't even begun to clean them up yet. we were planning on a light hand lapping to get them useable.
Oh...

I just saw the title of that post "cleaned parts" or similar, and saw the pics of rotor housings and irons right below, and thought "those aren't clean...".
Old 04-19-2010 | 01:17 PM
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Originally Posted by RotaryResurrection
I just saw the title of that post "cleaned parts" or similar, and saw the pics of rotor housings and irons right below, and thought "those aren't clean...".
Sorry bout that, the title of the thread was "Pictures of the cleanup" and i put the rotor housings under the "Before Cleaning" so i thought it was obvious.

But anyways, thx for your DIY. We used them on the engine removal.
Old 04-20-2010 | 11:12 PM
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Just ordered parts. should be here next week.

we will keep you updated on the rest of the build.
Old 04-21-2010 | 12:48 AM
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Clean up update

Rotor Housings: Sorry took pic with iphone







Circled is the chrome slightly flaking on the outer edge.
Old 04-21-2010 | 11:28 AM
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I would replace those housings with new ones..
Old 04-21-2010 | 11:36 AM
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Originally Posted by Turblown
I would replace those housings with new ones..
I think everyone including myself would love nothing more than to build new rotor housing engines all day long. But thanks to mazda's continual price hikes, it is not feasible for 95% of rebuilds, because it basically doubles the cost of the build right out of the box. The cost of rebuilding an engine is bad enough even if you are only replacing seals/springs.

Besides...in 50-80k more miles the 'new" housings will look like that again. Should it really be necessary to spend $4k on an engine build that will make 210rwhp and last for 50-100k??
Old 04-21-2010 | 01:08 PM
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Originally Posted by RotaryResurrection
I think everyone including myself would love nothing more than to build new rotor housing engines all day long. But thanks to mazda's continual price hikes, it is not feasible for 95% of rebuilds, because it basically doubles the cost of the build right out of the box. The cost of rebuilding an engine is bad enough even if you are only replacing seals/springs.

Besides...in 50-80k more miles the 'new" housings will look like that again. Should it really be necessary to spend $4k on an engine build that will make 210rwhp and last for 50-100k??
My thoughts exactly...

I've already spent $1500 on the rebuild and am planning on spending another $800. If I were to add housing's on top of that... yea it just makes no sense plus the majority of the wear is within factory spec, i'm not to worried. If I am going to go turbo id give it a second thought.
Old 04-21-2010 | 02:38 PM
  #61  
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Originally Posted by shadycrew31
P.S. just a warning the engine smells of dead rotting fish when you crack it open.
Stop premixing with Sardine oil!
Old 04-21-2010 | 02:49 PM
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Originally Posted by Nubo
Stop premixing with Sardine oil!
But its so cheap and accessible.
Old 04-21-2010 | 03:57 PM
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Originally Posted by shadycrew31
. If I am going to go turbo id give it a second thought.
even more of a waste of money if you were going to turbo it .
Old 04-21-2010 | 04:04 PM
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Originally Posted by Brettus
even more of a waste of money if you were going to turbo it .
I should have worded it differently. I wouldn't be going turbo for another 2 or 3 years at which point I'd rebuild the whole thing again, break it in, then slap on the turbo.

I figure in about 3 years those housings will be fubar. But ya never know!
Old 04-21-2010 | 09:31 PM
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Originally Posted by RotaryResurrection
I think everyone including myself would love nothing more than to build new rotor housing engines all day long. But thanks to mazda's continual price hikes, it is not feasible for 95% of rebuilds, because it basically doubles the cost of the build right out of the box. The cost of rebuilding an engine is bad enough even if you are only replacing seals/springs.

Besides...in 50-80k more miles the 'new" housings will look like that again. Should it really be necessary to spend $4k on an engine build that will make 210rwhp and last for 50-100k??
a man who makes sense and no bs... awesome!
Old 04-22-2010 | 12:31 AM
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Originally Posted by RotaryResurrection
Besides...in 50-80k more miles the 'new" housings will look like that again. Should it really be necessary to spend $4k on an engine build that will make 210rwhp and last for 50-100k??
I see your budget point but what will the OP's used housings look in 50-100k if reused? With this said, is it worth rebuilding an engine without new housings is the question? The purpose of 'rebuilding' an engine is to renew the service life of it, correct? In my opinion, if one is to invest the time and energy into refreshing their engine, there is no point in skimping on the single most important component within it. A flat wear surface for apex seals is key in building compression. Regardless if new seals are used. they will not magically 'break in' to the inconsistencies of used housings. This post is not aimed at RotaryResurrection in particular, I'm just expressing my opinion.
Old 04-22-2010 | 12:33 AM
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p.s. $1335 is not half of $4000.
Old 04-22-2010 | 12:39 AM
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Originally Posted by BigTurbo74
p.s. $1335 is not half of $4000.
wheres the 1335 coming from?
Old 04-22-2010 | 12:47 AM
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Retail on a pair of rotor housings from mazdatrix.
Old 04-22-2010 | 12:55 AM
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Originally Posted by BigTurbo74
I see your budget point but what will the OP's used housings look in 50-100k if reused? With this said, is it worth rebuilding an engine without new housings is the question? The purpose of 'rebuilding' an engine is to renew the service life of it, correct? In my opinion, if one is to invest the time and energy into refreshing their engine, there is no point in skimping on the single most important component within it. A flat wear surface for apex seals is key in building compression. Regardless if new seals are used. they will not magically 'break in' to the inconsistencies of used housings. This post is not aimed at RotaryResurrection in particular, I'm just expressing my opinion.
To answer your question in 50-100k the housing will be shot. But 50-100k is about 5-6 years down the road.

I'm 25 at the moment so in 5 years ill be about 30 and I will also have my degree. I will potentially be able to afford all sorts of wonderful things.

So In a perfect world I would have the money to get new housings, ceramic seals, lightweight rotors, a turbo, and every other part i drool over daily.

But I am an unemployed student living beyond my means so if you want to give me $1400 awesome. Otherwise I'm going to get another 5 to 6 years out of my engine.

If the housing's were terribly shot had cracks, chrome flaking beyond spec, and horrible chatter marks then yes I would replace them. The simple fact is everything is within spec so there is no need to replace them.
Old 04-22-2010 | 12:55 AM
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$1335 (Housings) + Seals, Gaskets, O Rings ($1500) + Labor + Random Parts = $4k... math solved.
Old 04-22-2010 | 01:19 AM
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Originally Posted by shadycrew31
To answer your question in 50-100k the housing will be shot. But 50-100k is about 5-6 years down the road.

I'm 25 at the moment so in 5 years ill be about 30 and I will also have my degree. I will potentially be able to afford all sorts of wonderful things.

So In a perfect world I would have the money to get new housings, ceramic seals, lightweight rotors, a turbo, and every other part i drool over daily.

But I am an unemployed student living beyond my means so if you want to give me $1400 awesome. Otherwise I'm going to get another 5 to 6 years out of my engine.

If the housing's were terribly shot had cracks, chrome flaking beyond spec, and horrible chatter marks then yes I would replace them. The simple fact is everything is within spec so there is no need to replace them.
I hear ya, I've been there as well. If you pay attention to all other clearances you will get decent service life out of your rebuild. My only point about used housings is that performance and efficiency will be affected noticeably. Good luck with the build, they are always fun to do.

Originally Posted by ///Mik3
$1335 (Housings) + Seals, Gaskets, O Rings ($1500) + Labor + Random Parts = $4k... math solved.
I'm just going off of the mazdatrix parts list. Your parts and labor pricing seems to be discounted and pretty vague. I'm really not trying to stir anything up, just voicing my opinion.
Old 04-22-2010 | 01:25 AM
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Originally Posted by BigTurbo74
I'm just going off of the mazdatrix parts list. Your parts and labor pricing seems to be discounted and pretty vague. I'm really not trying to stir anything up, just voicing my opinion.
so then its more than $4k in your words. either way, its more than he wants to spend. best option for him is what he has planned.
Old 04-23-2010 | 12:16 PM
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Anyway back tot he topic at hand. I've been researching assembly lubes to use and my head is going to spin.

I'm aware that most people including the factory uses Vaseline or something similar. Some people were even saying to use Crisco. If that's whats recommended by the top builders than so be it, I just cant bring myself to doing so.

With the Atkins Kit they sent a tube of hylomar not sure which kind but I'm assuming since its Atkins it will be the non pain in the *** type.

However I was looking more at the internals and what to use. I know Moly lube is quite popular.

I also found a hi zinc assembly lube which adheres to metal surfaces (thinking of coating the rotor with this stuff)

I mean the engine is essentially one giant metal to metal contact surface, so I'd like to get it as lubricated as possible. I know there are tons of assembly lubes out there some claim all sorts of stuff.

I'm kind of paranoid about dry starts but maybe I'm just over thinking the process any info would be great.

I'd preffer to stay away from a Vaseline and engine oil combo for assembly.
Old 04-23-2010 | 12:20 PM
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Since you're so paranoid about the first start-up why don't you use a good lube off the shelf and then the good'ol ATF through the intake nipples procedure?
I'm not saying that it is needed, i usually buy what's readily available but this could help you to sleep better


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