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04 2.3l swap to 2.5l successful

606K views 2K replies 112 participants last post by  MrkMazda 
#1 · (Edited by Moderator)
This post is a bit poor as im currently posting from my phone. So its a work in progress. Ill. Add step by step purchase list, total cost, and proof in pictures. And a q&a section. My goal is to get a sticky.

I wanted to share with the community that I successfully swapped a 2.5l into my 2004 Mazda 3 2.3l hatch back.

The short story. Got rod knock in my 2.3l motor needed replace. Wanted a 2.5 for the power and no oil leak problem like the 2.3l

Bought a 2011 ford fusion 2.5l motor simply because its way way cheaper than a Mazda brand motor. Its the same long block and that's all u really use. Stripped the ford motor down to the metal. Toss the ford intake, ford wiring harnesses, ford oil pan, ford heater hose block connector thing idk what its called, ford top mount temp sensor, ford intake cam, ford crank pulley, ford timing cover.


Basicallyall you want is the ford long block minus intake cam oil pan timing cover, crank pully, water pully, extra belt tensioners and oil pickup.

Then take pretty much everything off the 2.3 and bolt it to the 2.5 long block. Mazda oil pickup, oil pan, timing cover, intake cam shaft, intake manifold, camshaft position sensor, heater hose connector block thing, and all Mazda wiring.

The ford motor its automatic flywheel so swap that with you're Mazda flywheel and clutch and you need a new pilot bearing to. This would be a great time to get a new clutch if you need it. The clutch kit will come with a pilot bearing.

Here is the guide that i followed its for a Mazda 6 but its pretty much the same for the 3 with some differeces that i will detail below. The ford 2011 ignition and fuel rail are the same as the 04 Mazda. The ford fuel injector is larger to feed the bigger engine and needs to be reused it is compatible with Mazda wiring and ecu. The spark plugs are longer and i used those as well. The spark plug boots look the same so i reused the ford boots as they are newer than my 10 year old Mazda boots.

http://www.happywrenching.com/mazda/6/mazda-6-and-ford-fusion-23l-engine-swap.html


I will be periodically updating this post with more detailed information so check back regularly.

Step 1. Prep:

Purchase list

Ford fusion 2011 2.5L (lkq on ebay) est 600$
Intake manifold gasket (rockauto.com)
rtv silicon gasket maker high temp (walmart)
5qts motor oil (walmart) full synthetic 0w 20
3qts tranny oil (auto parts store API GL-4, SAE 75W-80Capacity 3 USqt
Antifreeze 1 gallon
Clutch kit (optional but you probably should do it if you near 100k)
Pilot bearing (Included in most clutch kits)
Crank pulley bolt and washer. (Got mine from the dealership for like 30$)

Optional: but handy
rust penetrate for all rusted crap
Lock tight high temp
Dielectric grease
Engine degrease

Required/recommend tools:
Torque wrench (required to to it right)
Impact gun (just get one so helpful)
Air wrench(ditto)
Diverse socket adapter set. Long short sockets, extensions, flexing adapters
Good wrench set
Car lifts so so nice otherwise tall jack stands and a crane
Pry bars
Breaker bars
pliers and things
A hose clamp compressor(this thing is awesome)
A coat hanger (thread through the axle holes on tranny otherwise the diff will spin and literately fall apart)

Step 2 get dirty and Pull the motor.
If someone has a good guide let me know and ill post it here otherwise follow the Mazda 6 guide i posted above its pretty good and 90% the same as our car.

Tips manual says to drop it out the bottom. Without a car lift and or a motor jack this sucks. Pull it from the top instead just takes some more wiggling.

CAUTION: when you remove both axles make sure to put the coat hanger through both axle holes. The differential gears are not locked it and they will spin and fall out of alignment. To fix this Right its a a total tear down of the transmission just to put the gears back in place. Happened to me it sucked bad but its not that hard.

Pictures:

THE PROOF Here is the shot of the back of the engine block stating its displacement is 2.5L



This is my car 04 2.5l Mazda 3S



This is the heater block thing. Its different on the ford and has the wrong hose connections. Its 4 bolts to take off fairly easy to do. All the hose connections are under it so i've highlighted the block in a green box.



these are the pullys. I had to remove the mazda crank pully and put it on the ford. Also i had to remove the water pump pully (Center Pully 3 bolts) from the mazda and put it on the ford water pump. Just the water pump pulley was swapped the ford water pump stays in the car.



This is what a pilot bearing looks like. its in the center of the fly wheel



This is the camshaft timing cog. NOTE: ONLY 04-05 HAVE TO SWAP CAM SHAFTS. 06+ its the same as the fords so don't touch the cam and Rock on.


This is the diagram that states that the 06+ are the same as the fords. It only goes to the 2009 but i can confirm that the 2011 ford fusion motor has the same timing cog as the 06-09s.






Part 3 Engine Tear down:

Mazda Eninge

These are all of the parts you will remove from the mazda engine and Transfer to the Ford engine block. BE ORGANIZED there will end up being lots and lots of bolts for everything. Seriously like 100+ bolts Keep it all organized it will make installation much faster. Half my time was looking for the dang bolt in the coffe can of a bazillion similar looking bolts. Good news is if you drop a few don't worry you have lots of duplicates from the ford motor parts you took off.

Head cover (optional: ford one has a big temp sensor hole i didn't like)
Main wiring harness
Ignition Wiring harness
Water block thing
Cam shaft position sensor
Intake camshaft (ONLY FOR 04-05)
Intake Manifold WITH throttle body attached
Timing chain cover
Crank position sensor
Crank Pully (CAUTION:Follow instructions installing this on the ford)
Water pump Pulley ( Only the pully you'll use the ford water pump )
Mazda belt tensioner
Alternator ( My ford didn't come with one )
Starter ( again didn't come with one on it)
Oil filter bracket thing ( for the oil pressure sensor and so jiffy lube doesn't get confused on what oil filter to use )
Oil Pan
Oil pickup ( Black plastic tube thing you'll find in the oil pan)
Oil Dipstick

Ford fusion 2011 motor
Now that you've spent about 4-8 hours taking all of those parts CAREFULLY off the Mazda motor DO IT AGAIN to the ford motor. But all of the ford parts can go into the trash or sold on eBay:

The ford motor has a temperature sensor at the top of the head in between the spark plugs. This is COMPLETELY unnecessary. Just remove it and toss it. Its a solid metal bolt hole so you don't need to plug it or anything like that.

This is what you should have left of a ford motor

Head
Block
Exhaust cam
2006 + cars can keep the intake cam
Timing chain
Water pump NO pulley
Spark Plugs (their longer and a little different)
Fuel injectors ( larger and needed to feed the bigger motor)
Fuel Rail
Spark plug boots (their the same as Mazda but their newer than your Mazda ones so keep em on)
Hope i didn't forget anything

Part 4 The install
Your over the hump all of the dissasembly is done Now that the ford block is stripped an prepared you can begin installing of the Mazda parts you carefully removed.

04-05 start with the camshaft. You will need the timing tools the guide listed. Follow the detailed instructions there. But i will help with an abridged version. Get the timing tools REQUIRED to do it right. Rotate cams to Top dead center. That mean the first 2 lifters (the oval loabe things) are almost pointing toward each other. The front of the cam shaft is the side with the timing chain. On the back of the camshafts is a slot. When at TDC you will be able to slide the timing plat into it. This will keep the cams aligned while you install the chain. When you install the crank pully later you will use this plate again. With the long peg insert it into the side of the block at the specified hole in the guide. Rotate the block CLOCK WISE until i stops against the peg. This is Top dead Center for the crank shaft. Secure the crank somehow so it doesn't rotate even slightly as it can still spin backwards. Now that the crank is secure at TDC and so are the cams Hook up the timing chain and make sure its all bolted down. Cam brackets bolt down to ONLY 16lbs. Thats very light torque these bolts are not grade 8 and you can break them really easily.!!!!!!!!!! DO NOT RELY ON TIMING TOOLS TO HOLD IN PLACE WHILE TORQING DOWN PULLY BOLTS YOU"LL BREAK CAMSHAFTS AND THE TOOLS AND YOU WILL BE PISSED!!!!!


Install the Oil pickup no gasket needed

Install the Oil pan with RTV Gasket maker High temp. BE GENEROUS AND COVER IT REALLY WELL. The last thing you want to do is miss a spot and have an oil leak still.

Install the timing cover. Same rule as the oil pan. LOTS OF RTV. There are also several bolt holes you in the middle of the pan you need to seal with RTV as well.

RTV take 24 hours to properly cure so don't put any fluids in your motor until its set up properly.

Install the crank pully

THIS IS CRITICAL: This is where you can ruin everything. (beside the cam swap if you had to do it.) Bust out the timing tools I KNOW YOU BOUGHT. The flat plate goes into the back of the cam shafts to hold TDC the long screw goes in a special bolt hole on the back of the block. It reaches all the way to the crank shaft. Spin the crank shaft CLOCKWISE will it hits that screw. This is TOP DEAD CENTER. Put the plate in the cams to keep them from wiggling at all. Now Slide on the Crank Pulley. Get out the new Crank pully bolt and washer. DON"T USE THE OLD ONE. This bolt is special its designed to crush and compress and hold the pulley by frcition and pressure. The old bolt won't compress right and can fail during operation. Rotate the pully untill the little bolt hole is at 6 oclock. Take the little bolt and slide it in there is a hole in the block it will line up with and screw it in by hand.

CAUTION: DANGER CAUTION: BRACE THE CRANK SHAFT. What ever you do do not torque down this bolt rellying on the timing tools to hold it still. You'll snap all the tools AND THE CAMSHAFTS WILL BREAK. They are not made to take the extreme torque your about to apply. Lock the flywheel somehow. You might be able to rent a flywheel lock from autozone or you'll have to make one. Or prace the crank pully with stuff. That little bolt in the crank pully will snap or In some cases i've read crack the block.

Ok having said that and everything is all timed up your ready to torque the Crank pully. First torque it down to 78ft lbs. The with a big ass wrench continue turning it an ADDITIONAL 90 degrees. Thats 1/4 a turn Do this slowly. Like push hard then wait 5 minutes. This is to let you rest as this is frigging hard and to give the bolt time to crush and cool down. I'm 270lbs 6'3 and am considered to be a strong man and i found this very difficult to do alone with just a 1/2 inch torque wrench. So grab a buddy and a big cheater bar to get it done. This end up being like 200lbs of torqe.

Good job

Now install the head cover

Great the crank pully and camshaft are the only sensitive and precision steps here. Now just bolt the rest of the parts back on the same way they came off the Mazda. Including the transmission. Make sure the tranny has the little push ring on the rod as it can fall out if its bumped. Grease up the input shaft and that push ring to prevent rust and provide smooth operation. After doing that my clutch is so much smother and easier to depress. It almost feels like its not hooked up.

Now put the motor back into the car. Everything will hoook right up as you have all mazda parts still.

Some problems i ran into
The hose on the back of the intake manifold had a different connector than the Ford. But it was easy to pull it out and put the Mazda hose connection in the block.

Striped alot of bolts becuse im impatient and didn't have rust penetrating oil.

Stripped bolts and broke bolts because i over torqued a lot of rusted crap or very small bolts like the ones on the oil cover and oil pan.

Couldn't remember how the wiring harness went on. That was a long jigsaw puzzle. I suggest taking Detailed pictures before you pull the motor OR as you disassemble all the little wiring brackets and routing paths.

First time starting procedure.

Fill the MANUAL tranny up to 3 qrts as most of the oil probably poored out the axle holes. (How much do the automatics take?) The fill bolt is 24mm and is under the frontside of the tranny and about 1/3 of the way up.

Fill the motor with oil. Since you used the Mazda oil pan your oil capacity is the same. about 4.7 qrts. Fill slowly and check the dipstick regularly so that you don't over fill it.

Now that everything is hooked up and bolted down tight disconnect the spark plugs.
Turn the engine for 15 seconds several times waiting before each crank to cool the starter

This process is to prim the engine with OIL WATER and FUEL.

Now that its had plenty of cranking hook up the spark plugs.

If you did it all right like me it will fire right up.

it will idle rough and run rough for about 50-100 miles as the ECU will be slowly adapting the fuel trims to an optimum value.

If you get any CELS check them out right away to see if they are anything important.

I got a Intake cam timing CEL for about the first 50 miles or so.

I had Major intake leaks as i didn't change the gaskets. I applied RTV on the top of the Gasket and that solved the problem. Its super ugly but i didn't have to take off the manifold as all the leaks were on the top. Picture coming later.


Thats about it. If there is any addition information i left out Please Please Let me know and I will update this with credit to you. Or if i need to rewrite anything becuse i suck at spelling I'll fix that too.

If anybody attempts this Your welcome to ask me question I'll provide all the information i can to help you out.
 
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#2 ·
Excellent news. I'm planning this swap soon. I bought this 3 a month ago and found out it's burning a quart every 400 miles. No smoke, no leaks, but the #1 cylinder either has bad rings or valve seals because the plug is caked and you can see the mess on top of the piston through the plug hole. The other three plugs look good.

So after you got the 2.5 installed, wired, and ready to go what happened when you turned the key? Was there any hesitation or issue? How much have you driven it since the swap?
 
#3 ·
You turn the engine without the ignition connected to allow oil to flow the after 30 seconds of the hook it up and it fires right up. It will run rough for 50 miles or so as the ecu is adapting the fuel trims. Ha0pens when ever you disconnect the battery on these Cars. Ive put 100 miles since the swap no check engine lights and it drive great and so much more power now to. If your in denver i could help you get it done.
 
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#6 ·
I'm planning to do the swap before my engine goes. Selling off the 2.3 parts will help to get some of the money back. Have you considered doing it that way?
 
#9 ·
Awsome thanks man! Im slowly updating this thread to have complete information so you have the best info to start your project. Going from a 2.0 to a 2.5 will be a huge difference in power youll love that.
 
#11 ·
My left overs are. 2.3 longblock minus oil pan timing cover intake cam crank pully oil pickup. Thats about it i reused pretty much every thing.

Left over ford bits
Intake manifold, oil pan, oil pickup, oil filer housing, intake cam exhaust manifold ignition coils, flywheel cam sensor, temp sensor, oxygen sensor
 
#46 ·
I'm in the middle of a swap now - 2011 Fusion 2.5 (15k miles) replacing the rod-knocking 2.3 (154k) in my '05 Mazda 3 hatchback mtx.

It's going well so far but I have a couple of questions, if someone could verify please.

1) I'm trying to decide whether to use the 2.3 or 2.5 valve cover. I'd like to use the 2.5 coils because of the lower mileage but am not sure about the compatibility of the 2.5 coils with the 2.3 valve cover and vise-versa, or even if the 2.5 coils will work with the Mazda 3's electronics. I can't tell for sure whether thlillyr used the 2.5 coils but in one place he said he had the ford coils left over, so maybe he used the 2.3 coils?

2) I just saw where Artem Vestsorov posted on 12-18-2014 on the happywrenching thread the following:

"I'll say one more thing about the 2.5 swap - technically yes it can be done. Someone correct me if I'm wrong but everything that I have read states that the 2.5 cylinder head has larger intake ports and a different intake manifold. So, if you use your Mazda intake manifold, you'll get a slight air leak because the manifold won't seal correctly with the larger ports. Or, if you use the Fusion intake manifold you will set off the check engine light."

I test fitted the 2.3 intake to the 2.5 head and the intake is VERY close to not completely covering the larger ports on the 2.5 head. Can anybody that has actually done the swap comment on the possible intake leak issue that Artem posted? I'm worried that I'll end up with an intake leak either immediately or somewhere down the road.

Thanks
 
#14 ·
+1 on pics. Any plans to dyno it? It's has to feel real nice now
 
#15 ·
Haven't looked into the bsd or what it entails. Would have been a good time to do it i bet.

Yes i plan to dyno it soon. My timing is a bit off as i did not install the cam with the timing tools. Got them now and will retime the engine. Once that done going to the dyno. As it is my butt dyno is grinning. Nice firm pull all gears and off the line is snappy and its very easy to spin the tires. Ecopia 422s.
 
#17 ·
Interesting, looking on car-part.com it appears that the 2.5L out of the Ford Escape, Mercury Milan, and Mazda Tribute ('09-'12) is the same part and would also potentially work.

Unless there is something particular about the Fusion motor?
 
#18 ·
Thats correct. I chose the fusion as its the cheapest motor and is far more abundant than the others. Even though its the same long block salvage yard's charge different prices for different branded motors and availability and selection goes down with less common cars.
 
#20 ·
#21 ·
Yes i had to swapp the cam shaft. 04-05 you have to swapp the cams. 06 and newer you dont have to swapp the camms as its the same. One of those small differences that start with the 06. Good question ill update the original post with that info.
 
#30 ·
Today i got my timing tools from massive, my ecu was throwing a cel for intake cam over advanced. I guess that's what i get for using screwdrivers instead of getting the right tools.

Also i will dyno this new set up after a few tanks of gas and i will post results here and on the dyno forums. Then ill get a dynotronics tune and post that too.
 
#34 · (Edited)
The mazda has an electric power steering pump thats mounted to the car not the engine so theres norhing you need to do about it. The ford motor has 2 long studs for its ps pump just remove them an toss em. If my ac compressor was not seized it would work just fine. I swapped the oil pan so it can mount to the engine and the mazda crank pully so i can reuse the belt.

I'll help you do the swap. I rented shop time here in denver at diy auto cost me about 1000$ for 3 days if time. But if you've got a garage and a cherry picker thats good enough.

I'm just a hobbiest but my wife says i have to charge 400$ for the project if you work with me. With 2 people it will go much faster. I dont ususlly charge but Mostly becuse i work 7 days a week and have to take time off for projects.

Pm me if you wanna come over and test drive it. We should drag race and post the results to the forum's.
 
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