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For those who just can’t get enough bad garage photography accompanied by poor technical writing, join me as I share my adventure in engine replacement. Crack open a beer and pretend you are the nosey neighbor leaning over the fender. I can almost hear it now – “Hey, neighbor. Whacha workin on?”

Disclaimer: I’m not in a big hurry and I probably won’t work on this everyday (gotta regular job like most folks), but I’ll post updates as I go along. I don’t always know what I’m doing, but my intuition nearly makes up for my complete lack of judgment. Follow my example at your own risk!

On with the project!

After clogged pre-cats ruined my engine, I decided to install a new motor and add a few mods along the way (more on this later).

History: I bought the 2003 Mazda 6s, MTX shiny new in February of 03. I did a few Autocrosses but never Mod-ed it like I did my old SHO. I racked up 140,000 miles in 5 years with the only mod being the Ipod interface. On July 1, 2008 (my birthday), the car started with a sputter and began to rattle quite badly. See the thread that started it all:

http://forum.mazda6club.com/index.php?showtopic=100313

After some hand-wringing, I decided to see if I could find a low miles replacement motor. I located a 3.0L, V6 from a 2006 6s, ATX car with 15,000 miles. There was some debate about the interchangeability of the ATX and MTX motor, but after asking around it seems it is limited to the engine wiring harness and other minor bits that can be transferred from one motor to the other. After lightening my wallet $1875 it was mine.

Time to get to work!

Step one was to get the car off the ground. I have a four-post lift in the other garage bay, but it is not well suited for dropping a motor and tranny out the bottom. Besides, it was occupied by another project (a story for another time). So I put the rear wheels up on ramps and supported the front on jack-stands. Place the jack-stands behind the sub-frame so they won’t get in the way later. As you can see from the cardboard under the car, I’m accustom to working under a lift and don’t even own a creeper (add to the shopping list).




To gain better access and improve the lighting, it is best to remove the hood. It really does make the job allot easier. You might guess I’ve never been one to spend hours detailing the engine compartment.



After all the fluids are drained (engine, tranny, radiator, power steering) we can remove the battery, air box and engine cover. It’s also helpful to remove the plastic under-cover (under the radiator) and the plastic splash liners behind the wheels.



Next are the shifter cables (don’t lose the clips) and the fuel line. I covered the fuel line with a plastic bag then wrapped it in duct-tape. I don’t want dirt getting in. I’ll replace the o-rings before it goes back together.



I removed the intake plenum primarily to improve visibility as I disconnect the engine wiring harness. If I gave a crap about this engine I’d stuff rags in the intake runners to keep debris from finding its way inside, but since it’s already toast - why bother? On second thought maybe I will – I’d hate to lose a socket down there. You’ll notice hoses and connectors with duct-tape on the ends. If you look closely you’ll see some writing. I learned a long time ago not to rely on my memory (too much partying in my youth).



Enough for one night. More later.
 

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good job so far. im assuming your going to pull the motor out of the top. i've alwayz wondered how easy/hard it would be to pull it from the top, because me myself i dont have a lift, so i'd be working like you.

i know most shops would just drop it out the bottom, and i read somewhere that it cant be pulled from the top, which is bologna.......

the main thing im interested in seeing is the disassembly of the balance shaft and removal of the pass. side axle. when i did my headers, it seemed like it'd be a pain in the ass, but once the headers(stock) were gone it looked pretty simple.

HERE'S A TIP FOR PULLING AXLES(in case you didnt know)

1. get you self a hammer and a big flat tip screwdriver/pry bar or whatever is flat enough and strong enough to fit between the CV and transmission

2. take your prying tool of choice and wedge it inbetween the CV and Trans.

3. pry on the CV enough to where there is good pressure but not enough to hurt it.

4. now directly opposite side of where you are prying........hit the CV right before the rubber boot.

the axle should pop out easy. again this is only if the axle doesnt come out by just pulling on it.


****you may have known how to do this already, but in case you didnt. now u do........just in case you dont have an actual axle puller****

i'll be keeping an eye this. keep me/us posted on the progress
 

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You couldn't have picked a better time to post this. I'm going to be swapping my motor in the next few weeks since I spun a rod bearing.
 

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QUOTE (The Great NY @ Jul 9 2008, 10:46 PM) index.php?act=findpost&pid=1386818
good job so far. im assuming your going to pull the motor out of the top. i've alwayz wondered how easy/hard it would be to pull it from the top, because me myself i dont have a lift, so i'd be working like you.

i know most shops would just drop it out the bottom, and i read somewhere that it cant be pulled from the top, which is bologna.......

the main thing im interested in seeing is the disassembly of the balance shaft and removal of the pass. side axle. when i did my headers, it seemed like it'd be a pain in the ass, but once the headers(stock) were gone it looked pretty simple.

HERE'S A TIP FOR PULLING AXLES(in case you didnt know)

1. get you self a hammer and a big flat tip screwdriver/pry bar or whatever is flat enough and strong enough to fit between the CV and transmission

2. take your prying tool of choice and wedge it inbetween the CV and Trans.

3. pry on the CV enough to where there is good pressure but not enough to hurt it.

4. now directly opposite side of where you are prying........hit the CV right before the rubber boot.

the axle should pop out easy. again this is only if the axle doesnt come out by just pulling on it.


****you may have known how to do this already, but in case you didnt. now u do........just in case you dont have an actual axle puller****

i'll be keeping an eye this. keep me/us posted on the progress[/b]
I'll be dropping it out the bottom (stay tuned). If you separate the engine from the tranny, you might get it out the top, but that would be more work.

I've had the passengers side axle and half shaft out previously. As you guessed it is a bit of a pain. I'm planning a slightly different approach this time (stay tuned).

More to come!

QUOTE (Mazda6sMtx @ Jul 9 2008, 11:04 PM) index.php?act=findpost&pid=1386825
You couldn't have picked a better time to post this. I'm going to be swapping my motor in the next few weeks since I spun a rod bearing.[/b]
Man, sorry to hear it. Let me know if you'd like to see anything specific as I we go along. I look forward to your report!
 

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Not sure about clogging but my cat on Bank 2 (front) just failed, so you are not the only one that has had problems with them, mine happens to be out of warranty.
 

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That's why I got the CPE headers, I didn't want to deal with the thousands of dollars for new cats just in case they failed.
 

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Discussion Starter #11
Another sweaty night out in the garage.

Believe it or not the topside here is ready to go. I know it's hard to figure out what is what. There are two main wiring harnesses with 5-6 connectors on each. All the harness and hoses you see on top of the engine will go with the motor. The harness you see draped over the upper-right shock tower stays in the car.



The clutch release cylinder is removed from the tranny and resting out of the way. It is best not to disconnect the hydraulic line - that way you don’t lose fluid or introduce air.



The rear crossmember brace needs to come out next. I couldn’t get a picture of it, but right above the oval shaped holes is the steering rack. It has to unbolted from the engine cradle/sub-frame and suspended. I’ll get a pic after I drop the frame out.



The bottom engine mount is next. It connects the engine to the frame to resist twist. They are prone to failure. Mine's still in goods shape because I replaced it not long ago. Near the bottom of the picture is the rear pre-cat that screwed me. I can’t wait to get a good swing at it!



About the next task is to remove the axles from the tranny. Having done this before, I’m going to try something new. Rather than dis-assembling the entire front suspension, I’ll disconnect the lower control arms from the frame and disconnect the tie-rod ends and swaybar end-links. This should allow me to pull the axles and let the whole assembly hang from the strut.



More to come!
 

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good job so far. word of advice to save you some time on getting the axles out.


you mentioned you were going to disconnect the lower control arms from the frame and disconnect the tie-rod ends and swaybar end-links..........correct?


why bother......

just unbolt the upper ball joint and the hub will be able to drop down and lean out/left or right whereever u need it to go to remove the axle. ball joint is one nut and a couple wacks with the hammer as opposed to un-doing a bucnh of bolt and nuts.

just a suggestion.


you're looking tho. Die Hard Mazda Owner. i love it.
 

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Discussion Starter #13
QUOTE (Macs&Mazdas @ Jul 10 2008, 03:16 PM) index.php?act=findpost&pid=1387208
Not to get off topic but, do the cats on our cars clog often?[/b]
I found at least 3 folks who posted the same problem on this board - I would assume there are many more that go unreported. Is it common - depends on your definition. It seems to occur after 100k miles. I think a contributing factor is the pre-cats are VERY close to the exhaust manifold. They see extreme heat and the slightest negative pressure will deliver debris back into the cylinders.
 

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QUOTE (CanyonRider @ Jul 11 2008, 11:07 AM) index.php?act=findpost&pid=1387982
I found at least 3 folks who posted the same problem on this board - I would assume there are many more that go unreported. Is it common - depends on your definition. It seems to occur after 100k miles. I think a contributing factor is the pre-cats are VERY close to the exhaust manifold. They see extreme heat and the slightest negative pressure will deliver debris back into the cylinders.[/b]
Close to the manifold is an understatement.Part of the manifold is more the truth.And yes there is a problem with them.Just like Toyota had with the MR-2 a few years back.
 

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QUOTE (The Great NY @ Jul 11 2008, 10:30 AM) index.php?act=findpost&pid=1387874
good job so far. word of advice to save you some time on getting the axles out.


you mentioned you were going to disconnect the lower control arms from the frame and disconnect the tie-rod ends and swaybar end-links..........correct?


why bother......

just unbolt the upper ball joint and the hub will be able to drop down and lean out/left or right whereever u need it to go to remove the axle. ball joint is one nut and a couple wacks with the hammer as opposed to un-doing a bucnh of bolt and nuts.

just a suggestion.


you're looking tho. Die Hard Mazda Owner. i love it.[/b]
I considered this. The problem is the frame has to come out. If the suspension is left attached, it becomes quite unwieldy (50lbs on each side). Also, in addition to the upper balljoint, you'd have to detach the strut (either at the top or the bottom) and the tierod ends (the steering rack stays in the car). It's kind if 6 of one; half-dozen of another.

Thanks for the ideas, though. I'll have the frame out tonight and post more pics. Also, I picked up the engine this morning - boy does she look shiny and new!
 

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The UPS Man cometh - bearing gift from far away lands!

CAI! Colder air - less restriction. :D



Light weight flywheel! Less rotational mass - Faster revs. :cool:



Stage 2 kevlar clutch! Higher clamping pressure- longer life. :yesnod:



Long tube headers & high flow cats! Less restriction - more power. :burnout:



Trunk mounted battery kit! Better weight distribution - more room in engine compartment. :p Moving a 40lb battery rearward 10' has the same effect on F/R weight distribution as moving a 400lb engine rearward 12".



Starter, clutch release bearing, pilot bushing, axle seals! :zzz: OK, not very sexy, but necessary.



In case the wife is reading, "Honest, Honey. All this stuff is absolutely necessary to fix the car!"

OK, enough drooling. Back to work.

Here is the driver's side. As I was saying, I disconnected the lower control arms, swaybar and tierod and was able to pull the axle out and let the whole assembly hang in place.



Not so on the passenger's side. The engine is coming out in this direction, so everything must be out of the way. Just disconnect the ABS sensor and brake caliper - hang them up out of the way. Then seperate the upper ball joint and lower strut pinch bolt and the whole assembly drops out. It's pretty heavy so if you're not careful it really will "drop out".



With the suspension disconnected and out of the way, the frame can come out. You can see the swaybar and lower engine mount are still attached.




As promised, here is a pic of the steering rack. It is unbolted from the frame (obviously) but still connected to the steering column. It is wired up to keep it out of the way and avoid strain on the steering column.



This pic shows the drivers side suspension from under the car. Also note the frame mounting stud in the upper left of photo. When I pulled the nut off, a fair amount of nasty water drained out. You can see the rust starting on this stud compared to the other one in the background. I suspect the water is coming down from the cowl vent (between the hood and windshield). This was a common rust problem area on my old SHO. Not sure what to do about it.



Anyway, now that the frame is out of the way, the accessories on the front of the engine are alot easier to get to. I need to unbolt the A/C compressor and hang it out of the way. Also need to disconnect the power steering lines from the pump (thats the line you see hanging in the driver side wheel well).

Enough for now. More later!
 

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While I'm waiting for a buddy to show up to help drop the motor out (gently), I thought I'd post pics of the new engine.






I Like it!
 
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