Down, but not out

[DOHCstunr]

well,
i start my car up in the morning yesterday.

idling perfect as usual...
put it in gear.
start pulling up the hill,

all of a sudden the car while in gear comes to a nasty stall.
no metallic sounds but abrupt nonetheless.
well shit.
i didn't even try to restart it
i hand't left my driveway yet so the first thing i do is grab the tools and pop my timing cover off.(figured the timing belt snapped or slipped)
saw some fibers on the t-belt but the belt still had tension, so i pulled my ecu fuse and had molly turn it over a few times whil i watched the belt.

everything was fine.

so i start it up. and its shaking bad. not a miss, but just excessive vibrations.

fuck....

its the balance shaft belt.

yeah thats right. only 6 months on it. brand new OEM.
set it myself,
adjusted the tensioner, tightened the tensioner pulley bolt, and measured the deflection with a metric ruler after the bolt was secure.

just another balance shaft belt gone bad.

this is the second motor its happened to me on.

first was my GS 2.4dohc. the belt snapped and luckily it killed my crank position sensor before it took out my t-belt.

on the 4g63. i was lucky again. cause if this happened while i was on the highway, i wouldn't have know until it was too late.


oh well, b/s elimination kit is on order from slowboy racing with the updated OEM MITSU stubby shaft with the new oiling groove on it to prevent oil pump failure.

I dodged a bullet guys.

[B19WHEELS]

Hey that was a good catch!!! Sorry to hear bout that though, Most people wouldnt have been that close to the house and would have tried to drive the car home,you got lucky...

[seth98esT]

Yah I dont care what anybody says(Sorry Mannybrew ) but the BS belt/shafts are just that, BS! I have been running without my balance shafts/bs belt for a few months ago and the extra vibration is not bad at all. If you use Mitsu OEM parts to block off the front BS and use the Mitsu stubby shaft for the rear BS, you shouldnt have any problems.

[peanotation]

good save, your motor is thanking you. this is the 837109571987255390012nd piece of evidence i've seen that proves the b/s belts are nothing but a time bomb

[manybrews]

Yah I dont care what anybody says(Sorry Mannybrew ) but the BS belt/shafts are just that, BS! I have been running without my balance shafts/bs belt for a few months ago and the extra vibration is not bad at all. If you use Mitsu OEM parts to block off the front BS and use the Mitsu stubby shaft for the rear BS, you shouldnt have any problems.

I seriously have no idea what you guys are doing to the balance shaft belts.
You must be dramatically overtightening them, or something, because they last LONGER than the regular belt.

[DOHCstunr]

i had the dealer do my first one. sam swope mitsu. largest dealership /mitsu dealer in kentucky. pretty nice shop too.
that belt snapped. and it took out my crank position sensor on my 2.4dohc.

this one i did myself and i measured the deflection with a metric ruler per service manual specs for the tension.

i'm just glad i caught it.

now i'm stuck w/ no vehicle until my parts arrive. oh well, after these parts arrive i'll debut my new setup.

[SkylineG1]

Damn man sorry to hear about this, and I like your G too. Does this happen alot too on 8G's?

[SuperGALANT]

if u have a i4..

[seth98esT]

<div class='quotetop'>QUOTE(manybrews)</div><div class='quotemain'><div class='quotetop'>QUOTE(seth98esT)</div><div class='quotemain'>Yah I dont care what anybody says(Sorry Mannybrew ) but the BS belt/shafts are just that, BS! Â*I have been running without my balance shafts/bs belt for a few months ago and the extra vibration is not bad at all. Â*If you use Mitsu OEM parts to block off the front BS and use the Mitsu stubby shaft for the rear BS, you shouldnt have any problems.</div>
I seriously have no idea what you guys are doing to the balance shaft belts.
You must be dramatically overtightening them, or something, because they last LONGER than the regular belt.</div>
Yah I dont know why John keeps breaking them. I am surprised mine didnt snap when one of my balance shaft bearings spun. Both timing and balance shaft belts were fine. I saw somewhere that they make an aftermarket kevlar belt for the Evos, wonder if they make one for the 4g63/4 as well.

I cant say that I noticed a difference in performance between balance shafts and no balance shafts. But I can say this, when spining the crank manually without balance shafts, it spins a lot smoother/more freely then it did with the balance shafts. Obviously the ~6lbs removed from the rotating mass will increase performance, but how much, who knows. Is it worth it? Depends on what kind of driving you do in the car.

[peanotation]

<div class='quotetop'>QUOTE(seth98esT)</div><div class='quotemain'><div class='quotetop'>QUOTE(manybrews)</div><div class='quotemain'><div class='quotetop'>QUOTE(seth98esT)</div><div class='quotemain'>Yah I dont care what anybody says(Sorry Mannybrew ) but the BS belt/shafts are just that, BS! Â*I have been running without my balance shafts/bs belt for a few months ago and the extra vibration is not bad at all. Â*If you use Mitsu OEM parts to block off the front BS and use the Mitsu stubby shaft for the rear BS, you shouldnt have any problems.</div>
I seriously have no idea what you guys are doing to the balance shaft belts.
You must be dramatically overtightening them, or something, because they last LONGER than the regular belt.</div>
Yah I dont know why John keeps breaking them. I am surprised mine didnt snap when one of my balance shaft bearings spun. Both timing and balance shaft belts were fine. I saw somewhere that they make an aftermarket kevlar belt for the Evos, wonder if they make one for the 4g63/4 as well.</div>

my b/s belt went out with only 40K miles on it. had it serviced at the dealer...so i assume it was properly set by a mitsu mechanic.

no one is doing anything to their balance shaft belts. there is such a thing as faulty engineering. A LOT of people have had their b/s belts go out on them even if the belt was installed professionally. it is another inherent problem with the 4g6x that has little to do with the installation process

[manybrews]

<div class='quotetop'>QUOTE(peanotation)</div><div class='quotemain'>
no one is doing anything to their balance shaft belts. there is such a thing as faulty engineering. A LOT of people have had their b/s belts go out on them even if the belt was installed professionally. it is another inherent problem with the 4g6x that has little to do with the installation process</div>
see, the thing is, its NOT faulty engineering. mitsu has used these belts and shafts since 1971. 71! the engineering has been well done in the last 30 years.
And keep in mind, ive been working on these 4g engines for 15 years now. Whilst I do occasionally see a broken balance belt, its never been below 100K miles. EVER. Ive seen MANY, MANY primary belts break much, much earlier than that.
so really, it is about the installation process.. I have seen aftermarket shops apply massive amounts of pressure to the poor little belt, until they're tight like piano wires. Obviously, thats way too much.
I believe you guys are suffering broken belts, but Im still gonna stick with them being incorrectly installed.

[4-G-rim]

faulty engineering is a bit much concerning balance shaft belts. I am with Manybrews on this one. Balance shaft technology is a patented technology of Mitsu even some other automakers used in their motors. I have several friends that have owned more DSM's than fingers on both or their hands and they say the same thing as Manybrews...its installation error most of the time. Though I don't think BS shafts are a bad thing...I prefer not to have them because of the somewhat performance gain you get by a more high spirited revving motor....thats just my own opinion.

[seth98esT]

I dont think it is something with the engineering persay, they are there for a reason and they do their jobs. But for $40 in genuine Mitsubishi parts, I can elimintae 7lbs off the rotating mass and never have to worry about that belt snapping and causiing more damage then its worth repairing. I dont know, Id rather worry about other things then that stupid belt

[peanotation]

when i said an engineering flaw, i meant that theres got to be some slight minor problem with the 4g6x engines and their particular balance shafts. the balance shaft on a 6g72 is obviously different than the b/s on the 4g64, how come the 6g72 b/s belts rarely snap? the entire design is great and works most of the time, but something about the 4g6x application just pisses the belt off

[DOHCstunr]

the only problem i could think of with the belt would be they are so short and spin so fast. thats a recipe for heat.
but i'm not saying that they aren't designed to take it.

honestly i don't think its an engineering flaw at all. the balance shaft system is fantastic.

but the belt on my 2.4dohc went bad after not many miles, and it was installed at mitsu by mitsu techs.

i did my past one and set it to spec. exactly how it was said in the manual. but i'm not here to argue for the cause of b/s deletion. i'm just saying it happened to me again.

so screw it. i'm going to make sure that never occurs in the future.

[Cali]

<div class='quotetop'>QUOTE(peanotation)</div><div class='quotemain'>when i said an engineering flaw, i meant that theres got to be some slight minor problem with the 4g6x engines and their particular balance shafts. the balance shaft on a 6g72 is obviously different than the b/s on the 4g64, how come the 6g72 b/s belts rarely snap? the entire design is great and works most of the time, but something about the 4g6x application just pisses the belt off</div>

6g72 does not have balance shafts.

actually, i dont think any v formation motors have balance shafts.

[peanotation]

<div class='quotetop'>QUOTE(Cali)</div><div class='quotemain'><div class='quotetop'>QUOTE(peanotation)</div><div class='quotemain'>when i said an engineering flaw, i meant that theres got to be some slight minor problem with the 4g6x engines and their particular balance shafts. the balance shaft on a 6g72 is obviously different than the b/s on the 4g64, how come the 6g72 b/s belts rarely snap? the entire design is great and works most of the time, but something about the 4g6x application just pisses the belt off</div>

6g72 does not have balance shafts.

actually, i dont think any v formation motors have balance shafts.</div>

no wonder why i havn't heard of any of them snapping.....well pick any other engine then

[DOHCstunr]

New parts came today.

-brand new complimentary manifold. fully ported.
-tial 38mm external wastegate stainless gaskets.
-mitsu ralliart 4 layer exhaust manifold gasket
-new lower injector seals to eliminate a boost leak
- throttle body gasket set
-RC 720cc injectors
- 60mm stainless turbine inlet gasket.
-a new t-bolt clamp for my throttle elbow coupler

- mitsu part number MD098626 oil pump stubby shaft for my balance shaft elimination.

all sent 2nd day air from sbr.
the guys hooked me up with free shipping and discounted my entire purchase. Very satisfied w/ their customer service.
highly reccomended

now i have to go work in my cold ass driveway cause i'm at school far far away from the comfort of my garage.

[manybrews]

<div class='quotetop'>QUOTE(seth98esT)</div><div class='quotemain'>I dont think it is something with the engineering persay, they are there for a reason and they do their jobs. Â*But for $40 in genuine Mitsubishi parts, I can elimintae 7lbs off the rotating mass and never have to worry about that belt snapping and causiing more damage then its worth repairing. Â*I dont know, Id rather worry about other things then that stupid belt </div>

actually, each shaft is only 2.2 pounds.. so you only save 4 and a half.

[manybrews]

<div class='quotetop'>QUOTE(Cali)</div><div class='quotemain'>

6g72 does not have balance shafts.

actually, i dont think any v formation motors have balance shafts.</div>
not on a mitsu, but there are many, many, many V engines with balance shafts.
chevy 4.3, ford v-10, chrysler 3.9 V-6, blah blah blah.
Hell, even my yamaha V-max (which has a V4) has a balance shaft.

Those engines (and others) are not naturally balanced for different reasons. The 4.3 is a V-6 that is actually a chevy V-8 with two cylinders removed. Because a properly balanced V8 has a 90 degree V, hacking 2 cylinders off makes it unbalanced. Hence the need for a balance shaft.
a naturally balanced V6 has a 60 degree V (which is what mitsu uses).