PDA

View Full Version : Craziest piece of machining youv ever done (or had done) Mitsu VR4



A.K. Boomer
10-27-2007, 12:46 PM
Warning; this story is long, but it would not due it justice to just tell of the machining part as its just a little peice of fabric of a much broader canvas...

Years ago I bought a mitsubishi VR4 Gallant, it was a 4wd turbocharged 2 liter DOHC inline 4 cylinder, little did i know that this car would turn into my nemesis, I had already shell'ed out more than i ever paid for a car, and was going to fix it up a little and make a buck, In the test drive I went through all the typical things, this car "appeared" to not need to much, it was going to be a good deal so I thought - even though I paid allot I stood to double my money, I systematically went through my check list of what I do to all the cars I get and then started picking off the individual problems that that particular car might have, close to last on my list of what I remembered in the test drive was an exhaust rattle, No big whoop i thought, it sounded just like a loose heat shield on de-accel at a certain RPM, or even better it could be rocks shaking around in the shield -- at the very worst it might be the Cat guts going bad in which case it would be another trip to a salvage yard and a few bucks,,, (I had already gone and scored a Turbo off an eclipse due to the Gallant having an erroded waste gate),
Then my life changed for a long long time, I went through the exhaust with a fine tooth comb, nothing, I beat on certain parts of it with a rubber mallet, tight as a drum. I took it for many more drives and said to myself "its got to be a heat shield or something of that nature", still no luck, then it hit me --- could this me a mechanical "rattle", and I thought -- I really never heard anything in a rear end/tranny/driveshaft sound anything like this, but It cant be ruled out, last but not least I was changing all the fluids anyways so I'll just see what comes out of the beast, the rear end fluid was probably original, very dark with some metalics, the tranny that also houses two differentials (the car has three) was much cleaner as far as color but actually had quite a bit of metalics in it, YUCK, yet the rear end had quite a bit of slop and was easy -- so I started there, Dissamembled for inspection, pretty good cond. reassembled and took some slop out, test drove the car, maybe an ever so slight improvment, but the problem was there ------- Not only that, the new fluid I put back in the trans appeared to already have "hash" in it just from testing the rear end, was this residual "hash" or was it "new" ---- Dear god, here we go --- I gotta pull the trans, so out it comes -- this unit has a five speed gearbox that then sends power to a front/rear differential splitter with viscous coupling inbetween, the rear finds its way to the PTO for the drivshaft but the front then in turn makes its way into another differential to segregate the front wheel drive, WOW, no wonder there's so much "hash" in the fluid, the only thing I can see upon close inspection however is some wear in the front to rear diff. splitter housing -- its not typical of a normal spider unit as it lacks a massive ring gear around it , so they just made this little half inclosed "drum" You could see where the parts went "frett crazy" in there, So I have to get this unit from mitsubishi for 240 bucks, and throw a 2nd gear syncromesh in while im at it cuz it was weak, bolt her all back together ---------- slightly better but still very noticably there,------- ugggghhhhh, Now I set up my little plastic paint cap cups all over the car, up front -- right at the trans -- at the rear diff. they all have hoses that are marked , I have my stethiscope modified to except the clear plastic swamp cooler line that lead to and are glued into the paint can lids that are strategically duct taped at all the different mechanical componenty under the car, all the ends end up in the cab right next to me ------- I varify that it has to be the trans UUUUUGGGGGHHHH, I dont do stuff twice, its very rare, I HATE THIS, out comes the trans, when I pull the drain plug and take my oil catch pan and look into the sun reflection with the oil I see more hash,,,,, Where in the fuqe ---------- just get it out and get it done, I get it all torn down, Im inspecting every single gear tooth every bearing every individual ball by rotating , I find some very minute details - replace a couple bearings, its not good enough to satisfy, but I got nothing, Put it in - same problem ----------- UUUUUUGGGGGGGGHHHH,,,dont panic --- its time to get drunk ---- went on a binger, vented to a few friends, got lost - got found, got lost again, all the while knowing the inevitable -- the Mitsu trans has got to come out a third time, but before that im going to be extra thourough in my testing, --------- next day my bro's driving the car down the road at close to 60MPH, weve got the hood bungied down around my body --- the bungies are strapped to under the front bumper and the bracing under the hood, im in there like a Mitsu sandwitch --- how symbolic im thinking -- this thing is going to eat me alive.......

My bro is making the noise happen, he gets it in the sweet spot of a slight de-accel, trouble is I cant take the heat, Im in my overalls but im roasting like a pig in a blanket, plus im worried about the loose parts of my overalls catching fire on the manifold shield -- I smell a hot italian, I start sceaming to my bro to pull over but at first he thinks im asking to make the noise happen more, I imediatly get my point across by screaming like a gurl, he pulls over and quickly unbungies the hood and I get the hell out of there --- Both thankfully and dreadfully, it was enough to verify that the transmission indeed has to be pulled,

At this point im like an animal in pain, its been going on for so long now that im actuially starting to get numb,----- Im hungover, miserable, and iv failed twice and its getting pretty grim, it was right then that things got even worse by one of the most simplist innocent things --- A child,,,,,,,, While I was under the Mitsu in my garage (again) that was in the alley I seen a mother and her son walk by like Id seen them do for the past month since I bought the car, it was almost a scheduled thing - and almost daily, I was under the Mitsu procrastinating --- wiggling things around and stalling for time -- looking for a miricle that would somehow save me from removing the trans, i dont have a tranny jack and My tri-ceps were fully cooked from the last install and I still had marks on my chest cuz thats what I use as a rest -- then the unthinkable happens, I hear the mother and child walking by and the young boy says to his mom --- Mommy - how come that man works on the same car all the time? i swear to you that it took everything I had not to cry,,,

A.K. Boomer
10-27-2007, 12:47 PM
So out comes the trans -- once again I cannot see a prob, so the trans sits, and it sits, and i start thinking about who the hell designed this mess, and it sits, and im obsessed with the "third shaft" and how the power has to go through a mainshaft, to a countershaft, then through the counter to a intermediate to then get diverted to two different pathways to which one of those pathways has to get once again diverted to even two more pathways -------- and the fretting on that one diff. peice, Its all adding up --------- it's piss poor engineering as one of these mechanisms has quite a bit of wieght to it and is actually mounted in the middle of a bunch of gears and mechanisms on either side of it!!!!!!!!!! thats what the fuqe it is -------- You cant do that, the slightest play will get amplified in the rebound effect, it will eventually gain clearance and the amplification will snowball and so will the clearance,
No wonder nobody in the salvage yard has a trans, thier all junk, So I price a full set of mitsu gears, about half as much as I paid for the car --- no can do,
So the trans sits --- (for a couple more days), then I walk into the shop one morning and start mapping things out, Im going to move all the gear clusters closer to each other, I need to map out what ones and how much, The mainshaft has to remain the same --- all the others I can manipulate, I will push the counter further into the main, and I will push the intermediate further into the counter --- How will i do this? I will bore out the counter and intermediate bearing mounts in both tranny case halfs - offset - and then install the apropriate feeler gauge material all around the bore with locktight stud and bearing mount, it will take a semi warm case and a rubber mallet to get it together but will go nowhere, it will be a bastard to dissasemblle --- but thats not my problem, At this point im more concerned with a solution, any solution,
I take both case halfs to my machinist friend, he asks me over three times "are you sure this is what you want to do" I say yes, he CNC's it, I pay him and im off, get it built, put it in ---------- Test drive it -- Nice......... No noise, after 500miles inspect the fluid for metalics ---- sweet.

Gentalman shows up from Denver to buy the car, he is a mitsu GURU, he is astounding with his data base on this car, he had the hood open for 15 seconds and then we went for a test drive, he stands on it and then says, well Just as I expected -- the turbo spools up imediatly but thats due to the fact that someone put an eclipse turbo on this motor --- it OK -- some guys actually do it but if you run them all out all the time it gets into the waste gate to much, The Gallants are cammed slightly different --- I'll be replacing it anyways with after market ------ I asked him how he knew and he stated it was the numbers on it, OK (wow, all in about 15 seconds and looking at everything else...)

Then he takes it out on I-25 ,, puts it through the tests of shifting fast and stuff, then we hit an exit ramp, and I notice he's playing with the drivetrain loads upon de-accel, Im like ------- Oh God -- he hears something, he keeps working it --- then he looks at me and says --- this tranny is unreal --- Its the tightest one iv ever felt, these things have major problems, all of them, I said "they do?" he said yeah, I might be able to run this -- and then he stated that after he was done with the engine it would be pulling close to twice the ponies and he thought he'd have to go a new trans with upgrades,

I dont want anyone to think im a shyster, im the type of guy that if there is a hole in the carpet underneath a floormat you will know about it --- but I paid my dues with that ride and did not want to miss this sale as it was not moving and took a guy from denver to drive all the way down to buy it, So I let him ------- and he was happy - and even though I probably made 5 bucks an hour on that car I was happy too -- or at least out of my misery,


Its true things like this strengthen your resolve,
Now when any car gives me a rough time I just laugh at it and say -- NO way you win,,,,, you have no clue as to who the hell your up against.....:cool:

aostling
10-27-2007, 01:24 PM
I've forwarded this thread to a friend who is a rocket engineer, but an ASE-certified mechanic prior to that. I think you deserve a special place in some honor roll, for this venture.

A.K. Boomer
10-28-2007, 12:00 AM
Thanks Al, I gave mitsu's one more try, I bought an eclipse with a blown motor, I asked the seller if the trans was good and he swore up and down that it was, after allot of tire kicking I told him I could handle one heavy hitter and need to know the trans was good to go and he got a little peeved and stated that it was perfect, I bought the car - i rebuilt the engine, I took it for a drive I remember on new years day, the tranny was total hash, it was actually missing a tooth in second gear, I called the guy back and he stated and I quote "oh well --- you bought it" My reply was "yeah but now I know where you live" I hope it made him worry some, what a way to start a new year,
And then people wonder why i hate people,

Me and Mitsu's arent and were never "meant to be" and now it is my decision to keep it that way, Never say never ------ unless your talking mitsubishi.

Scishopguy
10-29-2007, 06:12 PM
AK,

This story reminds me so much of my son's experience with an Eagle Talon he got for a couple hundred bucks because it had a blown motor. THe timing belts had broken and it ate the valves. He was in Vo Tech school at the time and thought he would do a quick fix up and make a killing on the resale. He proceeded to work himself to death and actually learned quite a bit about that little all wheel drive. He ended up keeping the car as it was in good shape interior wise. He has rebuilt just about everything on it and it is his daily driver now. He really loves the turbo. Kills his gas mileage pretty good too! ;) He is a Ford mechanic now and it kills his soul that the Talon can beat his beloved Mustang. I think he gets a kick out of driving it to work.

later,

A.K. Boomer
10-29-2007, 07:20 PM
Scishopguy, thats crazy, the eagle talon is a mitsu eclipse, same car --- same drivetrain, I feel his pain...



He got lucky if all it did was eat valves when he blew a belt, they have "floater" rockers, this means the rockers are not physically attached to anything, they are simply held in place by design, When the valves stuff they dont return all the way, this allows roller rockers to shoot out in every direction, some get caught between the cam lobes and head, if it happens in the hi R's it can totally ruin a cylinder head, snap cams, and basically destroy everything in the cylinder head even though the cam drive belt has already given way (Iv fixed many of them for people over the years)

BadDog
10-29-2007, 08:00 PM
Usually called "followers" rather than floaters, generally characteristic of overhead cam designs (at least in my experience). Basically sprung in place between a seated hydraulic "tappet" on one side, and the valve stem on the other, and "following" the cam above it's span. And yeah, I've seen the destruction from a blown belt. But then again, I've been able to make "repairs" on followers that would blow your mind (and make me ashamed to admit it. :o), so it's a bit of a mixed bag.

A.K. Boomer
10-30-2007, 12:59 AM
Badog, it sounds like me and u could exchange some stories!, I call them floaters cuz Iv seen "followers" like yer talkin where they pivot on a shaft at one end and have adj. on the opposite end, (and are actuated by the cam lobe in the center)Its almost the exact same layout with one huge diff, they cannot physically leave the "area" unless they themselfs break or thier holding mechanism, a floater is a different story, its totally floating, It is the sum of either one or more parts keeping it "captive" ------ in this case it leaves as soon as the valve spring either "floats" as in floating the valves at high RPM, or as in a mitus's blown belt case stuffs the valves allowing extra clearance at the lowest cam lobe profile --- then that allows a "floater" to float wherever it wants too, where-as a follower would just sit there and take a spankin.

It really is kinda my bad, but when it comes to valve trains Iv worked on about everything from around the world and then some of my own creations,,, so i end up coming up with my own kind of "lango" to describe things because one little detail changes everything... or at least can...;)

BadDog
10-30-2007, 12:47 PM
Hehe, not a problem, "floater" is quite apt and I've picked up more than a few for the head floor when they had vacated their assigned position. <grin> And yeah, I've read some of your stories and thought to myself, "Heh, I've been there, that sucks..." ;) I dissassembled and rebuilt my first car, a 340 'Cuda, when I was 15 in my Grandfather's basement, owned/operated a mechanic/body/rebuild shop (not all at once, but worked all positions from frame machine to electrical, mechanical, and on to spraying paint - sometimes in the same day), and even gave a go at owning/running an auto salvage operation. So I've been around on that road. :D

BadDog
10-30-2007, 12:54 PM
BTW, one of those "stories" involved a quick race day fix for a dirt (circle) track Pinto 2300. It shed the follower previously (wear), and now had done so again, and there was no time to get in parts and rebuild the OHC. The wear seemed isolated to the follower and the cam still looked at least decent, though a bit galled on the edges as I recall (some 20+ years back). I got him through the night by experimenting with random washers dropped into the bore below the tappet to take up some of the wear slack till I got something resembling a proper fit. :D It made it through that night and several more weeks like that, until it finally got the complete top-end job it needed.

Not exactly machining, but crazy enough for a race motor fix I think.

A.K. Boomer
10-30-2007, 01:08 PM
BTW, one of those "stories" involved a quick race day fix for a dirt (circle) track Pinto 2300. It shed the follower previously (wear), and now had done so again, and there was no time to get in parts and rebuild the OHC. The wear seemed isolated to the follower and the cam still looked at least decent, though a bit galled on the edges as I recall (some 20+ years back). I got him through the night by experimenting with random washers dropped into the bore below the tappet to take up some of the wear slack till I got something resembling a proper fit. :D It made it through that night and several more weeks like that, until it finally got the complete top-end job it needed.

Not exactly machining, but crazy enough for a race motor fix I think.



There are real mechanics in this world and by the book guy's, if you do things strickly by the book you only know what someone else has already done, what a drab existance, I bet your friends vote you as a favorite to be stranded out in the middle of nowhere with...:p