How To: Assemble A Forged MZR DISI Motor
I have been meaning to do this for a while but have procrastinated like no other. Its about time I got to it.
For those who don't know. I built two forged motors that are identical in every way save for the oil cap; mine is the red aluminum MazdaSpeed unit and the second one is the plastic pos. The first engine is currently in my car and the second one is neatly packaged in the house looking for a new home.
The pictures below were taken from both builds. If you see a mild change of scenery, you'll know why. Also, towards the end, the pictures get a little spotty (I'm missing a few) so I'll try to explain it as best as possible.
Onto the walkthrough.
Prepare your workstation and put the block onto the engine stand.
Lay everything out neatly so you know where it goes. By the end of the assembly, your shit will be everywhere but at least you tried, right?
Grab the oil squirters and attach them to the block. With the Wiseco and Carillo setup, I had to slightly bend the squirter further to the center so the piston skirt wouldn't make contact. Don't bend them too much as you may weaken the metal.
Prep balance shaft delete kit and install it. I put some threadlock onto the bolts for peace of mind.
Grab some assembly lube and with your finger, spread it onto the bearing journal on the block.
Lay out the main bearings in order. My engine builder (Competition Automotive) numbered them from 1 to 5. Bearing number 1 goes at the front of the engine (timing chain side). The bearings come in two pieces; ones with oil passages and ones without. The halves with oil passages are positioned on the block side and the halves without get positioned on the girdle side.
Also notice that the half with the oil passages on bearing 3 is different. This is the thrust bearing and gets mounted on the block side (as mentioned earlier).
Grab the bearing halves with the oil passages, apply assembly lube on the inside of the bearing with your finger then position them on the block. Make sure they are properly centered in the journal.
Next, grab the crank and drop it in (slowly!).
Apply assembly lube onto the main bearing portion of the crank in preparation for the other bearing halves.
Position the bottom halves of the bearings onto the crank in numbered order.
Grab your ARP MAIN studs and apply a generous amount of ARP Ultra-Torque lube onto the threaded portion without the hex shape on the end. Thread the studs into the block.
There are 10 main studs total. I found that it took a while to thread these things in without some assistance so I grabbed the proper hex head, put it on a screw driver handle and went to town. Be sure that you thread the studs all the way down until they stop. DO NOT ADD TORQUE TO THE STUDS ONCE THEY BOTTOM OUT AND DO NOT USE POWER TOOLS. If you do either, you should be slapped.
Apply assembly lube to the girdle journals. Don't be stingy but don't go nuts (this applies to using the lube on any necessary surface on the motor).
Gingerly align the girdle onto the studs and drop it in. The girdle only fits in one way without resistance. If you fail at putting together a puzzle, don't assemble a motor.
Grab the ARP Ultra-Torque lube and apply it liberally to the stud tops. Then, insert the washers and nuts accordingly. Hand tighten them down.
ARP recommends tightening the girdle down in 3 passes to a maximum of 60ft-lbs.
Ensure you tighten them in the proper order (pictured below) in 20ft-lbs increments.
The crank is now securely fastened. Rotate the block upright for the next phase of the build. Also, grab your old crank pulley bolt and thread it into the crank; it'll become quite useful.
Lay your piston/rod (with rings) assemblies and corresponding rod bearings onto a flat surface. I had Competition Automotive assemble the piston to the rod for a small fee. On the second motor (pictured here), the also put the rings on. Unfortunately, I don't have pictures of the ring install from the first motor so I'm going to skip this step.
Grab piston/rod number 1, remove the rod cap, apply lube to the inner AND outer portion of the bearing halve for rod 1 and press it in. It'll require the tiniest bit of force for it to seat properly. Note the notch on the upper right-hand corner of the rod and the corresponding notch in the bearing; they only seat one way.
Apply some motor oil to the outside of the piston. Don't be stingy but don't go nuts; apply enough.
Then, position the piston/rod combo into your ring compressor tool. Ensure the piston top is parallel to the top of the ring compressor and that the piston skirt hangs out juuuust a little; it'll help with alignment.
Stuff a shop towel down the cylinder bore to prevent the rod from nicking the crank when it drops in. Lube the inside of the cylinder wall with some motor oil then position the piston/rod combo with ring compressor on top. Ensure the ring compressor tool is perfectly centered AND that the valve reliefs on the piston tops are facing the PCV/water pump side of the engine.
While holding the compressor tool with one hand, use the rubber handle of a hammer to gently tap the piston/rod down the cylinder bore. Competition Automotive said I could do it in one shot but I was too much of a wuss to do it that way; I went with the multiple-gentle-tap method. (not pictured unfortunately).
IF you feel any sort of resistance while trying to tap the piston/rod down the bore, chances are one of the rings is resting on top of the block surface which is preventing the whole assembly from going in. Remove the piston/rod, reposition it in the ring compressor and try again.
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Originally Posted by boyracer
