ichibandan

iTrader: (1)

Situation: My 93 FD is leaking oil from the rear main seal, front cover, turbos, and OMP. At this point, the motor has ~85k on it, so I figure it's about time to rebuild it anyways.

Here's what my options are so far (from easiest/most expensive to more difficult/less pricey):
1) Have local rotary shop rebuild the motor for me.
2) Order a reman from Malloy, redo any gunky gasketwork that's accessible without cracking open the motor, swap long blocks, send core back.
3) Order full rebuild kit and new housings, and a rebuild video, fully tear down the motor and build it back up.

Of these options, #2 is looking the most appealing right now since it's less expensive than option #1, and not having to tear down the motor reduces the number of items I need to precisely measure while putting everything back together (human error factor). The thing that scares me is the stories about MANA rebuilds being sloppy. Is this still true today?

Mainly, I'm also posting this to see what other people's opinions are. This would be my first rebuild.

tec 9

i seened a friend rebuild opened one up, seems easier than what i thought.rotors have certain way 2 go in. think with the video u will do fine.

charlies7

iTrader: (4)

I vote for option 3

There is nothing better than taking pride in your own work. New housings might not be needed depending on the condition of your current ones but new ones would never hurt. DIY 13b-re has a great 4 DVD collection on the how-to's of an engine build, and if your into porting mazdatrix has a porting dvd along with templates.

I say go for it, great learning experiance .

bzwigart

iTrader: (9)

My first rebuild was done by a shop. My motor went a couple months after purchasing the car. At that point I knew little about the rotary and my best option was to leave it to an expert. Having a shop do it is not a bad option. Drop it off.....pick it up....drive the car. Nice and easy.

However, after a few years of owning the car, I think I would opt to try it myself.

alexdimen

iTrader: (13)

I rebuilt an FC non-turbo before I did the FD. The FD engine bay is much more complicated and has alot of quirks.

If you're experienced and have a nice tool collection you can pull it off as long as you follow the shop manual to a T. Otherwise, I'd say start smaller and simple.

Sgtblue

iTrader: (16)

5 months ago I had the same decision with a coolant seal failure at 87k.
Option 1 was possible, but expensive. On the other hand, you get warranty.
Option 2. I intended to call Ray at Malloy. He's about as reliable you'll find. Ask him to pick out a good reman, hopefully with new housings. $2600 + core (IIRC $1000). About $150 shipping each way. Total $300 shipping. I intended to break the motor apart to check for matched rotors and get a peak at the irons and e-shaft. You'd have to buy a few gaskets but if everything was OK, just re-assemble. If all is well, total after core is returned will be about $2900.
Option 3. If you've never done a rebuild before, don't try it without some experienced help, an appropriate clean space (garage) that can be tied up for a few months to do the work, and a willingness to buy a few tools. I ended up taking this route, with a very knowlegable friend who'd done maybe a dozen other rebuilds. I have a small shop, bought parts through MazdaComp including new housings, hard and soft seal kits and all four new bearings. Ended up with about $2300 in parts, about $200 in extra tools (pilot bearing remover, large socket for FW nut and engine stand adapter. I had micrometers, feeler guages etc. If you don't, figure to buy them. You should also figure a silicone hose kit, sme DaleClark check-valves and a few other incidentals like Hylomar, Hondabond, anti-seize, assembly lube etc. By themselves it's not much, but it adds up.
I'm glad I went my route. Breaking it in now and all seems well. YRMV.

Sgtblue

iTrader: (16)

From this

To this in just 4 months. Piece of cake.

Sorry about post whorin', couldn't help it.

dhays

iTrader: (1)

I'd go for option #1.

I could actually see rebuilding a motor, but it is the thought of pulling it and reinstalling it that would scare me to death.

mgoddard1

It was the opposite for me, pulling and reinstalling the motor was manageable but the thought of rebuilding the motor gave me pause. Fortunately for me at the time Ray the OEM parts deity that he his got his hands on some brand new motors so I dropped one of those in.

Hitokiri_Gensai

iTrader: (2)

i say option 3. Its a good skill to know.

zenofspeed

iTrader: (1)

I've heard lots of bad things about remans..

I'd go for option 1 or 3. Personally, I wouldn't mind rebuilding a motor on a workbench, but have no experience or tools for pulling it out.. I may just do a blend of 1 and 3 myself. I may buy a rebuildable 13b keg (cheap) and rebuild it myself, then have a shop perform the R&R ($1200).

That way I'd know how to rebuild so next time around I'd just need to tackle the R&R part.

What is your compression? Get that checked, if it is high and stable, no reason to rebuild at all..

Montego

iTrader: (1)

Option 1 is better than 2. if you have a rotary shop do everything for you there won't be any finger pointing in case anything goes wrong.

Option 3 that depends on your skills

alexdimen

iTrader: (13)

Good catch. Front cover, turbo oil returns, rear main, and OMP o-rings don't even require removal of the intake or turbochargers... they do however require some serious labor.

A rebuild probably won't even fix the OMP leak anyways, since the end plate seal is probably what is leaking. I've got the OMP-->front cover and the end plate o-rings (not avail from mazda) in SAE/ASE Viton. PM me if you're interested, I sell them dirt cheap since I had to buy bulk rate in order to get one for my OMP.

ichibandan

iTrader: (1)

alexdimen: I figure with the amount of leaks going on and the labor involved to fix them all, it would be a better use of my time to just pull the motor and rebuild it anyways since it's got ~85k on it already.

OK, just got an estimate back for option #1. Let's just say only options #2 and #3 are left now. I've called Ray @ Malloy and got prices for full rebuild kit plus new rotors. The price for that is roughly the same as getting a reman (hopefully with new rotor housings). Does anyone have any recent experience with remans from Ray?

I should also mention that I'll mostly likely be working on this in my friend's shop. I don't want to lean on him too much and have my car in his shop for several months while I rebuild the motor. In this regard, option #2 is better because I should be in and out of his garage quicker than if I go with option #3.

EDIT: Order is placed for both of the Bruce Turrentine videos (one for engine R&R on 3rd gens, and one for engine rebuild). This should give me a better idea of what I'm getting myself into.

Sgtblue

iTrader: (16)

https://www.rx7club.com/showthread.p...ighlight=Reman

ichibandan

iTrader: (1)

Reviving this thread with an update:

I'm going with option #3 here (rebuild motor). Here's what I've done so far
- Ordered the Bruce Turrentine videos and watched both of them casually (should probably watch them again and pay more attention)
- Bought and received a motor a week ago which I've started disassembling

Here's the near-term plan (feedback appreciated, thanks!):
- Finish disassembling motor and bagging all the little parts
- Hot tank all metal parts
- Send out irons to get lapped and streetported
- Mic housings to check if they are in spec (or order new ones)
- Order Pineapple Racing engine stand adapter and rebuild kit minus apex seals
- Order Rotary Aviation 2mm super seals + racing springs (does anyone have experience with these?)
- Order SS OMP lines
- Order new rotor bearings
- Send out irons, housings, corner seals, e-shaft, gears for WPC treatment (friction reducing surface treatment)
- Replace rotor bearings
- Order new water pump, oil pressure sender, oil temp sender, water temp sender
- Replace all coolant and vacuum lines with silicone
- Replace OEM fuel pressure regulator with aftermarket (from what I understand, this is a common source of fuel leaks. If possible, I'd like to relocate this to a place that's easier to service)
- Check and replace dead solenoids
- Source Efini y-pipe
- Send old turbos and Efini y-pipe to BNR for stage 3 turbos
- Send out injectors for flushing and flow testing (sent injectors out to witchhunter before, which was a good experience, I'll likely have them clean my injectors again)
- Do thermal pellet bypass? (not quite sure what this is yet, need to do some searching)
- Order custom copper/kevlar clutch from local clutch builder
- Order new pilot bearing and throwout bearing
- Source auto counterweight and lighter flywheel

Once the rebuild is done, the plan (after break-in of course) is to safely run about 15psi on the newly streetported motor with PowerFC, HKS RS intake, FMIC, downpipe, stock cat (for now), and Racing Beat exhaust.

Questions:
- Do I need to balance the rotating assembly once I have that ready to go?
- Will the OEM injectors will be running beyond 85% duty at that point?
- Will I need a bigger fuel pump?
- Does anyone bore out the throttle body, UIM, and/or LIM with good results?

So far, the following items are off: UIM+TB, vacuum hard pipes, solenoids, water pump and the housing behind it, oil injectors, sensor above the spark plugs (knock sensor?), oil pressure and temp sensors. Today's goal is to take the flywheel nut, flywheel, and main pulley off and figure out how to take the turbos and LIM off.

Sgtblue

iTrader: (16)

*The experienced friend that helped me emphasized cleaning everything really well.
*Do the wax thermo-pellet replacement. After you read about it and find out how little it costs, it's a no-brainer IMO.
*I don't remember seeing alot of talk of the fuel pressure regulator failing, but did read alot of reports of the fuel pulsation dampener failing. I replaced mine with new, but IIRC Mr. Sanders at Banzai Racing now has a how-to on removing it, apparently with no ill effects. I think most aftermarket fuel pressure regulators have an integrated dampener, so you have choices here.
*Consider an oil pan brace.
*Good time for a set of aftermarket engine mounts.
*If you intend to replace rotor bearings, why not front and rear main bearings as well?
*Consider a new clutch fork and throw-out bearing with the upgraded clutch and pressure plate.
*Get a set of DaleClark's viton check-valves to go with your silicone hose kit.
*Consider a new coil harness and plug wires.
*Consider removing the double-throttle.