I'm saying it right up front. This video goes above and beyond shortblock rebuild parts for a reason. Read on... The first part is stern, the last part is happy.
Nobody in their right, left, forward or reverse minds puts a 23-year-old 4g63 engine back together with 100% OEM parts. Nobody's shooting for that good ol' stock 190hp feeling with a DSM drivetrain. Nobody. Not unless they've got something to prove.
I am putting a 7-bolt head on a 6-bolt block. So with that said, I show several over-the-top internal parts that are and are not related to the short block itself. I show cams and valve springs which only matter for head work. Not part of the short block. Nobody makes an engine gasket kit with all the parts mixed and matched to do this. So what people have to do is order both kits, or order all the individual parts separately like I am doing here.
It's at this stage you are working with a machine shop to return your old worn-out block to the specs you've chosen to follow, and you need these cylinder head parts at this stage of the game to do it right. These parts making an appearance in this video show 3 things... 1) I am not aiming for a stock build 2) Now is the time to have your cam and valve springs if you're going to make any changes to the head. 3) these gaskets, seals, pins, bolts and bearings are things you will need no matter what it is you're building if it's a 6-bolt block. When I do the head series, I will be showing modifications and parts to rebuild and make a 7-bolt head fit a 6-bolt block.
This video assumes you disassembled a running or freshly-broken engine and that YOU HAVE ALL THE BOLTS, NUTS, WASHERS, and HARD PARTS of the motor that it needs, bagged and tagged like was demonstrated in the "Crankwalked?" video. You've watched me clean and inspect valves, lifters, rockers, crankshafts, rods, etc. I don't need my turbo, hoses, vacuum lines or anything like that yet, and they likely won't be for a MHI turbo anyway. This video focuses on the gaskets, seals, bearings, consumable and disposable parts that you should replace for the shortblock only. My old trusty 6-bolt front case is coming up in a future video, getting refurbished and rebuilt, and ssembling a shortblock doesn't require having timing components yet. The head gasket will probably get its very own video just like the front case.
As you can see, I have very big plans with this upcoming series. We've hit the 200's on engine stuff. It's a milestone.
For you 7-bolt guys... bah! I know this is all 6-bolt part numbers. Some parts are interchangeable but I didn't make it clear which ones are in this video. Don't worry, you will need these part numbers eventually (I hope that was a joke). But if you wait long enough, perhaps I'll be re-assembling a 7-bolt again? Here comes the first bit of good news...
The reason the "Crankwalked?" video had a question mark in the title is because I wanted to see others' comments about it. Gain a consensus. There are so many different opinions about shortblock failures on the 2g cars that I didn't want to take sides with such an entertaining video. But it's not crankwalked. What you see is rod bearing failure as a result of torsional stress on the crankshaft. It was caused by a catastrophic clutch failure. The thrust bearing was .014", and crankwalk cars that fail from crankwalk are usually around .075"-.150". My thrust bearing was beat to death as my old 6-puck fragged. All the fail was initiated by the drivetrain, and the drivetrain problem was a fail by yours truly that had repeated several times prior to me making videos about it and getting it right. It's my fault for not catching it, but when I discovered it, the drivetrain series was born. So my 7-bolt crank is trashed, but the mains are fine. New bearings and a crank would fix its thrust measurements and I may just rebuild it for the sake of a video someday.
Now comes the really good news. My brother is working with me to build a website. There will be tech links and things that simply can't be delivered on YouTube. Not in a practical and effective way anyway. Things like schedules, projects and mod lists, parts lists, bolt lists, torque specifications, printable worksheets for blueprinting, the parts I used to make my fuel injector cleaner... stuff my viewers need or ask for. Soon you'll know where to find it. I need to learn how to maintain it, but I'm a good student. Still, these things take time, and I haven't yet wrapped my own brain around its potential. I'm putting it out there for you guys because you deserve it. I'm simply astonished at how the channel has grown, and I feel the need to give back.
Cylinder Head 201 - Radius Cut Valve Job
This video covers the complete valve job process that your machinist might
perform. If the 100 series videos didn't help you identify and correct a
problem with your cylinder head, then this is the next step. This video is
brought to you with permission from my machinist in full 1080HD, and covers
cleaning up the head inside and out, preparation and setting up a radius
cutter, cutting all 16 valve seats, valve grinding, and spans 3.5 hours of
actual work in under 30 minutes. There's nothing like this anywhere else
THANK YOU BALLOS PRECISION MACHINE. Thank you for the professional
explanation and execution of a job excellently-done, and un-precedented
access to your facilities.
A valve job is done by re-grinding or replacing valves, and then having new
seats cut to match the faces of the valves you're using. There are several
different machines that might be utilized to achieve this result, but the
process is the same no matter how it's done. There are seat cutters that
utilize cutting stones. There are valve seat cutters with 3 separate
angles installed 120° out-of-phase, and there are single cutters with all
3 angles (radius cutter) that cut with one blade in one pass. The machine
demonstrated here is a Sunnen VGS-20 Radius Cutter. This machine (now out
of production) produces a gradual curved seat that's superior to the shape
of a traditional 3-angle seat. While a radius cutter does contain the 30,
45 and 60 degree angles, it does so without leaving any sharp edges between
My valve selection includes Supertech 1mm oversized nitride-coated
stainless steel undercut and back-cut intake valves, and 1mm oversized
Inconel back-cut Exhaust valves.
Inconel is a high-temperature alloy utilized in marine and forced-induction
performance engines that can handle more abuse than steel can without
melting. The other characteristics of the valves which are discussed
typically yield bigger gains in airflow than simply using a bigger hole and
a bigger valve.
Why I did this to a perfectly-good cylinder head:
I changed cams. Because the valves were previously recessed during another
valve job 9 years ago, my valve installed height was increased and this
raised the operating positions of my rocker arms. My new camshaft
selection dictates using the stock valve install height. The only
solutions to this valve install height problem are to either replace the
valve seats, or install oversized valves. I opted for the latter.
7-Bolt Shortblock Failure - Full Diagnosis
If you are your own mechanic, there is no more important character trait
worthy of development than the ability to own your mistakes. That's where
the line is drawn between good mechanics and bad mechanics. It's not the
failures but how they deal with them that measures their ability.
In short, it's not easy to admit you did something wrong or were negligent.
But if you don't own it and talk about it, it doesn't get fixed, and
nothing positive can come from it. It was my quest to overcome my clutch
issue that lead to the creation of a video. That video is the textbook
perfect guide for how to correctly install a DSM transmission.
Crankwalk as described is caused by a casting defect. This was not a
defect. This was preventable. A lot of people would find something like
this and not tell anyone out of embarrassment. I'm not ashamed. It's my
fault. I got good use out of this engine and it was tough enough to make
it 48K miles since the last rebuild despite my abuse. I'm here to tell you
if you bought a used car that's had its clutch replaced, or if you ever pay
someone else to do it... make sure it has this bolt. It's stashed away
between the starter and the transfer case, so it's hard to see. Make sure
all of your bell housing bolts are torqued properly because fastener
problems can destroy your shortblock, clutch and transmission. If your car
fails because of a mis-aligned transmission, you have no reason to blame
It wasn't until I bought my next AWD car that I discovered there was a
smaller bolt on the other side of the block. I destroyed 3 transmissions
in the GSX first. With the damage already done to my crankshaft, I then
lost a shortblock. It's an ounce of prevention that's worth metric tons on
your bank account.
Grade 10 M8x60 bell housing bolt = MD706012. It gets 22-25'lbs of torque.
Owning my mistake permits me to learn from it through con$equence$, and
never repeat it. What good would it have done anyone else for me to learn
this lesson and not share it? That's why I'm providing this video to all
of you. Sharing it can perhaps help someone else avoid this costly
mistake. This is the final chapter for my 7-bolt, and this book is going
back on the shelf.
Here are some valuable resources if you're trying to read bearing damage:
And of course, now that I've covered the complete oil system, transmission
and driveshaft series of videos, you now have all the tools necessary to
ensure your 4g63 lasts a very long time. Whether the casting defect
exists?... or it's all caused by a bolt, or the harmonics, or whatever...
Sure, crankwalk exists and it's horrible. But with the small amount of
movement required for your crankshaft before it contacts the block isn't
far enough to make your clutch drop to the floor when you turn. You'd be
hearing woodpeckers and jackhammers on the crank long before that clutch
pedal would fall to the floor. Some people are going to hate on me for
saying that. That's fine. I believe all of the people who experienced the
clutch pedal issues had fastener problems on their bell housing.
DSMs get a bad reputation for this but we can change that. Crankwalk is
never the cause of your engine failure. Crankwalk is always a symptom of
the real problem. It's your disease that makes you deny it's your fault.
You've got the 'itis. DSM-itis.
Whenever you dig deeper, you'll discover what applied all of those thrust
loads to your crankshaft to begin with, and it's not going to be a casting
defect that moves your crank .101". Mine only went .014", but all of the
same parts failed.
PLEASE tell me in the comments if you find this bolt is missing from your
4g63 Block Oil Gallery Mod
This modification is intended to improve your 4g series engine's oil
delivery. People frequently discover large chunks of flash in their
engine's main oil gallery. It's because the galleries are part of the
cast, they're not machined into the block. There is also a very rough
sharp edge where the main oil gallery is bored into the block, and oil must
make a slightly greater-than 90° turn in order to begin its course to the
parts it lubricates. Both of these conditions cause turbulence in the oil
flow. My goal in this video is to eliminate as much of that as I can.
This is a cheap and easy modification if you have the tools, and the
patience. Any engine with cast-in oil galleries could probably benefit
from this. Be careful not to cut into the high pressure oil gallery or
else you will circulate un-filtered oil to the #1 main, oil pump, and rear
balance shaft. You will also deprive the rest of the engine the oil
pressure it needs to operate. So in short, punch a hole in that and it's
trash. I did this my way, everyone may choose to do this a different way.
I just wanted to make this video to raise awareness.
Also, there's a great thread on DSMtuners about this. Pictures and
everything. Written by a machinist and friend of the DSM community. Go
give him some reps because he's posted a lot of great info about the DSM
oil system over the years.
Blueprint 108 - inspect the deck
There's a reason why there are no subtitled specifications in this video
for the block. It's because they don't exist in either service manual, 1g
or 2g. You're not supposed to remove material from a block on the deck
surface because it has ill effects on parts of the combustion chamber
geometry, and alters your compression ratio. It can be done intentionally
in some cases for a desired side-affect, but if you have to deck a 4g63
head, it would be advised to use a thicker head gasket. The Mitsubishi
Multi-Layered-Steel or MLS gasket is slightly thicker than the OEM
composite gasket. Also, HKS, Power Enterprise, Cometic, and other
performance brands all make MLS gaskets that are .065 and thicker.
THERE IS ONE ERROR IN THE VIDEO. I said a block with .002" warpage is
junk. I was completely and totally wrong. While I don't wish to spread
misinformation, I don't think it's a big enough error to warrant re-editing
this video. I just wasn't paying attention. .002" warpage on a cylinder
head is the service limit before it needs machining. I meant to say
.02"... or two HUNDREDTHS (not thousandths) of an inch.
...and here's my justification...
A warped block to me is junk either way even if its minimal because your
MLS gasket will never seal unless both the head and the block are perfectly
flat. Trust your machine shop to get the values for how much is taken off,
and buy the correct thickness gasket for your machine work.
A factory head gasket (composite) is .051"
The MLS Mitsubishi gasket is available in the stock .051 and a .062"
Cometic makes gaskets up to .072"
There are some brands that go as high as .127", but I'd have thrown both
the block and head away long before then.
6-bolt 4g63 Kiggly Main Girdle Install
Ballos Precision Machine was nice enough to let me into their operations
and film the installation of my 6-bolt Kiggly Main Girdle. They let me do
this as a gift to all of you.
THIS IS NOT THE FINAL INSTALLATION.
Though all the parts were cleaned prior to pickup, they will be extensively
cleaned again, and the fasteners installed finger-tight with red Loctite
exactly 15mm above the surface of the main girdle and torqued in the proper
My main caps were level and straight, the crank bore was straight to begin
with, and had never been line bored following the original assembly at the
6&7-Bolt 4g63 Front Case & Oil Pump Rebuild
Here we disassemble, clean, inspect and rebuild both popular 4g63 front
cases. This is not difficult, you just need to know what to look for.
Something else that happens in this video is the analysis of one of the
factors that caused my 7-bolt engine to fail. It wasn't the only cause,
and we'll talk about that later, but left to its own devices and without
the other contributing factors, it would have been the only cause.
Major Huge Announcement
This video is a quick update on the projects here on Jafromobile right now,
as well as a tour and history lesson on my latest addition. I'm always
hard at work to bring you all new material based on Mitsubishi production
and partnerships from 1987-1999. Also covered are what's necessary to
resurrect a car that's been sitting for many years. If it's got a 4g63, to
me... it's always worth saving. My channel now has 4 Mitsubishi-powered
projects in the works which should be capable of delivering tons of new
I'd like to welcome all of you from the forums. My history with Mitsubishi
began in 1997, and hasn't taken a day off since. Owning one of these has
been long overdue for me, and you guys have been a wealth of knowledge that
helped me along my travels. An asset to the DSM community, even though
this isn't a DSM.
2g 7-bolt 4g63 Engine Removal & Disassembly
Tearing down the GSX to see what broke, and what I need to buy. Sitting
for a year and letting the battery drain took a toll on the polished
finish... and it looks like a piece of 4th gear wanted to take a look at
the outside world. Holy transmission case, and it's off to TRE to see
what's salvageable. Looks like the clutch could stand to be replaced, too.
Timing belt has taken some abuse from the higher rev limit and I was
expecting that. EGT probe is fried and I don't even care. Since I'm
running DSMlink and can log Boost,
I'm removing all my gauges anyway. Front case seal (freeze plug) is
leaking a tad, and the crank seal shows signs of excessive crankcase
pressure. I'm going to make some changes... I've got a lot of other
tricks up my sleeve, so stay tuned.
Cylinder Head 103 - Deck Tech
How to clean, inspect, and determine what you can do with your cylinder
head. Also how WHAT you do affects your oil system. There are many
variables at play when you make changes to your cylinder head deck from
your oil system, compression ratio, your valve timing and potentially even
disaster. 'best not to go that far with it. Watch this video and avoid it
if you're building your own 4g63 head.
The differences between this head and a 1g head are mostly related to port
sizes on the intake and Exhaust, and
different sized head bolt holes. The 7-bolt uses an 11mm bolt, and a
6-bolt uses 12mm. 1g heads have gigantic intake ports, but aside from
that, valve geometry, oil system functionality and the service limits are
all the same.
Also, click these links for in-depth discussions about oil port
modifications for all generations of Mitsubishis, and specifically for 2g
head installations on a 1g block.
4g63 Oil Port Modification:
2nd gen head on a 6-bolt block:
Possibly 2 of the best threads on 'Tuners for anyone considering a
1g-in-a-2g or for anyone that wants to know everything about a DSM oil
Colt Driveshaft Install Part 2/3
It cost me $55 to have my driveshaft shortened. They even painted it at
that price. After rebuilding the Colt's driveshaft I clear up the process
and complete its installation. I discuss fabricating the front carrier
bearing mount and positioning it, illustrate pinion angles, and hit 2
points left out of the driveshaft series. Those two points being the
grease volume in the Lobro boot and using Loctite during assembly.
No fancy audio track this time. Rumor has it some people had trouble
concentrating, and we're going to cover a lot of ground fast. It's also
extremely difficult to generate 18 minute songs just to have them
permanently get hung in YouTube's copyright arbitration. So this time it's
just a detailed explanation of how this worked out for me. No
The driveshaft was shortened as the final edits were being placed on the
last video. I jumped right back into the garage to bring you the next 12
hours of footage in just under 18 minutes. There's no perfect recipe for
an AWD Colt. Everyone bakes theirs a little different. I convicted myself
to share its entire transformation and potentially my fiery death in it on
YouTube. Hopefully not the latter.
I just want to clear something up because I don't want a flame war about
this again. I'm not here as a professional mechanic handing out diplomas.
If someone learned anything from my experience, that's the reward in
hanging out here. Anyone is welcome to disagree with my methods at any
time, but I'm not going to argue or volley about this subject with anyone
in 500 character comments unless it's constructive. If anyone wishes to
complain about me breaking bolts loose by hitting my wrenches with a
mini-sledge, you're welcome to simply explain a better method that worked
for you on these parts.
You can't fit sockets over the bolt heads or nuts so you can access them
with impact wrenches or breaker bars. There's a carrier bearing tight up
against the nut side, and the bolt heads rest against the lobro joint's
metal boot cup which is not dimpled to allow access for a socket. If you
strip out the 7mm allen-head portion of the bolt, you'll never be able to
torque the bolts back down. If you use a torch there's a high probability
of starting a grease fire. A grease fire isn't very easy to stop. Most
people take apart a Lobro joint because the boot is ripped and grease is
leaking out. You have fuel, you have air, don't add fire.
No it's not good for your tools to hit them with a hammer, yes it's
dangerous because wrenches can become airborne, but if you do this over a
workbench and take precautions, it's extremely effective and you won't get
hurt. I have little concern with a 12mm crescent wrench if it's all that's
standing between me and having a 500hp AWD Colt. If you manage to break a
wrench, they're still much cheaper to replace than a fire extinguisher. I
received dozens of complaints about shop ethics, but this is an acceptable
means of breaking bolts loose when all else fails. It's the nature of red
thread locker. I figured it was better to explain this here in the
comments so others will firstly understand why it's not the ideal method,
but most of all why it's the least-dangerous method. You will injure
yourself far worse if the jaws of your wrench spread and you smash your
knuckles against something when it slips off. I respect the reasoning
behind others' concern on this topic and I don't want anyone getting hurt
either... so consider that your 12mm wrench may be expendable on this job,
and proceed at your own risk.
But the other thing I left out of the driveshaft series... make sure you
have a fresh tube of red loctite handy. I thought I had mine before I
started the job and it was hard as nails. You need red loctite on your
I do indeed fail at important things from time to time. I'll be sure to do
it on-video and make a public example of myself when I do so we can all
learn from it.
6-bolt 4g63 Crankshaft Chamfer & Oil Clearances
These are some things you need to think about during your build. Some
engines don't have any chamfer on oiled journals whatsoever. All equipment
like that can benefit from at least a light chamfer like the one that's on
a stock Mitsubishi crank shown in this video.
When you Chamfer an oil passage, you create a low-pressure zone where the
edges of the oil passage lift away from the bearing as it passes over it.
The principles of fluid dynamics dictate that if there wasn't an available
substance to displace that low pressure zone (in this scenario, there is an
oil supply), cavitation might occur. If we were talking about
aerodynamics, the effect would be lift.
An extremely-advanced or leading chamfer is actually capable of sucking oil
off of a flat bearing, whereas a trailing chamfer vacuums oil out of a
gallery and does a better job of spreading it around.
The modification that was performed here is intended to increase oil flow
to the mains and the rods. It's mentioned in the video that I'm setting up
my rod oil clearances on the looser side of spec. This will decrease block
oil pressure because more oil will be able to leak past the fillets of the
crankshaft and back to the pan.
But there's another modification being performed. A balance shaft
elimination. There will be lots of debate about this in the coming videos
as that transpires, but one of the side-affects of doing a BSE is increased
oil pressure. With several internal oil holes plugged off inside the
block, I will have a spike in oil pressure. I had my chamfers cut straight
in order to offer the largest practical surface area to apply oil to the
mains and rods. My intention is to relieve some of this oil flow that
doesn't have anywhere else to go. With the added flow, the straight
chamfer is actually beneficial to the mains, allowing them to intake more
oil as well as to spread more of it on the flats below the grooved upper
The animations illustrate this completely. They were created by
yours-truly. I know the oil hole on the mains is on the wrong side. It
was too much work to fix, but they get the point across. Don't laugh at
them any harder than I did.
Cylinder Head 101 - Remove Cams Rockers & Lifters
Going through a 4g63 Cylinder Head? You're on the right channel. I don't
know how many parts there will be to this series, I suppose it could go on
forever... We all have different ways of doing it, and I'm going to show
This video won't put a dent in most people's grey matter outside of
entertainment value... but I tried to keep it fun. I'd like to leave at
least a small dent. But no music in these because they're going to cover a
lot of ground and fast. I'm not doing anything difficult. This part of
this job really isn't. Most everybody pays someone else to do the
complicated stuff for them, and those people do it every day so it's still
easy unless you earn your money to pay for it from difficult and degrading
But this video's about getting started. There's some safety and
organization tips to be aware of before diving in. Stuff that could help
people whether or not they even own a Mitsubishi. Everything else is in
Blueprint 103 - Connecting Rods
Connecting rods are the crux of the engine. They're responsible for
carrying the force of the explosions that occur in the combustion chamber
and using it to turn the crankshaft. Oil clearance specifications of the
"big end" and "small end" are crucial to maintaining consistent oil
In this video we take 3 measurements:
Rod Journal (also called Crank Pin) Diameters
"Big End" Bore diameter
Using the Journal diameters and the "Big End" Bores, you can calculate your
oil clearances of each bearing. The process is illustrated here. Anyone
rebuilding an engine who doesn't know its history should check all of these
clearances whether or not they're re-using the rods. If the crank,
bearings or connecting rods are going to be replaced, it's imperative that
you measure the new parts as well to ensure they're in spec.
4g63 Oil Filter Housings
The link to my website is here BUT THE DATA AND PAGES ARE NOW BEING
CREATED. I couldn't leave you without a video any longer. I really will
have a link here very soon that goes straight to the information. To prove
I'm not bullshittin' you... here's the website. http://www.jafromobile.com
It's full of placeholders and copy I did not write. Though I did not write
it, the author knows me very well! There will be highly-detailed
measurements of all the pieces parts available shortly.
I suppose if there was anything else I needed to say here it would be...
these are the filter housings I got my hands on and tested. They happened
to be from each of the models of the mainstream cars with a 4g63 in the
United States with only one exception (EVO III). There may be variations
from year to year, but to be as specific as I possibly can, read on...
The 91-94 housing I demonstrated is specifically from an early 1992
6-bolt/4-bolt turbo AWD car. The one I
call 95-99 is specifically from an October '94 built 1995 model Eclipse
GSX. One of the '90 OFH's was brand new, and the other one on the Colt
came from a 1990 Plymouth Laser FWD.
The Galant housing I have no data on. I was told that's what it was. It
may actually be from a non-turbo
Eclipse? The 1990 factory service manual has an illustration of this oil
cooler-less unit. I've never paid attention to this in the junkyard and I
haven't owned a NA 4g63. Do the 1g non turbo DSMs even have oil coolers? You guys know
better than me.
The non-turbo oil filter housing is the
least restrictive because it has the longest spring installed depth. The
non-oil-cooler blocks are the no-oil-squirter blocks. Get how these are
similar? You put an oil cooler on this thing and your pressure goes up.
Look at the charts.
Put an external air-oil cooler on a 1g? Your pressure goes up. Put the
Evo III housing on a 2g? Pressure goes DOWN. High oil pressure can result
not just from how you built your motor.
Last thing to say... Yes, you could easily INCREASE your spring installed
height by using a THICKER crush washer. That would lower your pre-load,
opening pressure AND piston travel across the port prior to spring bind.
Could you double-stack crush washers? Probably. Will it leak oil? I'm
sure it will eventually. Either bore the cap deeper or machine a 1 piece
part is my recommendation. Would I try it with stacked crush washers?
Most definitely. Look at what you have to do to remove and port it.
4g63 Balance Shaft Elimination - bearing modification
This is the first part of a two part series about balance shaft elimination
on 4g series engines. This video details the bearings, the other video
will cover the front case modifications. I've already got a low-def video
of the front case mods, and I plan to re-shoot that one in HD when I'm in
the assembly phase. It's linked in the video.
The balance shafts are designed to cancel out harmonic vibrations caused by
combustion and the spinning rotating assembly. They may offer a greater
degree of comfort to the driver and passengers, but with that comfort comes
Often, when a 4g63 timing belt gives up, it's because the balance shaft
belt breaks or comes loose and takes the timing belt out with it. When
that happens, it can total your pistons, valves, damage the crankshaft,
wrist pins, timing belt tensioner and crank angle sensor. Basically, it
can total your motor. The balance shafts also have a combined weigh over
10 lbs and both are driven off the timing belt making them additional and
heavy rotating mass. If you've got a lightweight flywheel but still have
balance shafts, you have your priorities mixed up.
So here's what you do with the bearings. It's easy. You can do this at
home. You CAN do it with the motor in the car, BUT DON'T. You must enjoy
punishment to do this like that.
The end result will slightly increase your oil pressure, but usually not
enough to cause concern unless you have a full-circumference bearing turbo, ball bearing turbo--with your oil feed coming off the oil
filter housing. The head feed would be better in that case because it's
regulated at 15 PSI.