Attention 7 bolt 4G63 owners!!!! The truth about crank-walk

[1000whpTSi]

Lots of people speculate about the cause of crank-walk,but none have done as much R&D on the subject as Magnus. I have never ran a 7 bolt in any of my cars,but I know there are guys/gals out there that still do. Well,this is for those of you that are among those people.
http://www.magnusmotorsports.com/tech/crankwalk.htm

[DsmRob]

There was a lot of good info, thanks for the link.

[97TurboDSM]

didnt read the article but my 7bolt with 133k miles, 16g, act2600, and supporting mods had no signs of crankwalk and was strong as hell. dunno what the big stink about crankwalk is. i'll read that article eventually.

[2G_TSi]

Thanks for the link

[1000whpTSi]

didnt read the article but my 7bolt with 133k miles, 16g, act2600, and supporting mods had no signs of crankwalk and was strong as hell. dunno what the big stink about crankwalk is. i'll read that article eventually.

They are out there. I've just heard about more crankwalking 7 bolts than I have about good 7 bolts.
As they said in the article an early sign of crankwalk,the noise the trigger plate makes when hitting the cranksensor.

You can also measure endplay with a dial indicator to see if your out of spec.

[Fastrick25]

I highly doubt if your 4g63 especially if it hasn't walked already wil do so now, oem motor is what 16-19 old now.Do your maintenance and turn the boost up and enjoy:cool:

[Got Insulin?]

97-99 thrust bearings were junk and got borked by heavy clutches and their inheirent weak design. My 93 origional shortblock has seen over 400hp and a 2600lb clutch with ease. It's all in that bearing and clearances.

[Eclipse GSX 61]

My stock 1997 7 bolt has 143,XXX and it is still running strong. I don't see the big stink about 7 bolts.

[90blacktsiawd]

I ran my old tsi for 50k with crankwalk. I didn't know what that was when i bought the car :o

[1000whpTSi]

I've been working on DSM's since they came out. I worked for Dutchess Dodge Mitsubishi for 9 years. I've seen thrust bearing failure on cars with high mileage,low mileage,and some right off the showroom floor. The reason they were not recalled was due to the fact that these failures were inconsistant.
I have a 7 bolt in my shop right now that walked. It belonged to a kid that had been using the car for DD'ing for over 125,000 miles with no issues. He purchased an upgraded pressure plate and a few days later,Tadah'.....crankwalk!

Eclipse GSX 61, you said "My stock 1997 7 bolt has 143,XXX and it is still running strong". Stock is the key word here. start increasing power output and upgrade your clutch than see how long it lasts. Maybe it will last,maybe it won't. I've never been the type to leave things up to chance.
I can't say that all 7 bolts walk. Back a few years ago Extreme motorsports had a FWD 7 bolt car that made close to 600hp. But in the long run they experienced crankwalk as well.

I think you guys are taking this post the wrong way,lol. We could sit here and discuss this all day long. The truth is 2G 7 bolts walk. Maybe not all the time,but enough to deter people from running them in anything but a stock DD. Some people won't even use them for that. ****,my 1993's 7 bolt has been sitting in my garage for the last. I swapped it for a 6 bolt with 40K miles on the clock and the crank is fine. I just was'nt going to try to run mid 10 second passes in an AWD car with a 7 bolt. This does'nt mean I think everyone should do the swap. ****,run it till it shoots the crank out like a cannon. I just wanted to share this info with those of you who run 7 bolts.

[97TurboDSM]

not arguing they walk, its a given. I, personally, have never experienced it nor do i know anyone that has. I've owned two 7 bolt's one was completely stock, 2nd one, not so much. i guess i've had good luck but solid maintenance and anyone that pays attention to it should be able to prevent it.

[laser92dsm]

I just bought my first 7 bolt thats in my talon but i havent had any problems with it and i have an intake on it running stock psi. I only plan on putting in a 6 bolt if the motor is done for good. and thanks that article had alot of good info.

[Eclipse GSX 61]

I'm running an intake and exhaust and I have had an ACT 2600 and a Fidanza Lightweight flywheel on there for the past 25k if that makes a difference.

[BlkWhtTSI]

My stock 1997 7 bolt has 143,XXX and it is still running strong. I don't see the big stink about 7 bolts.

only 1995-1996 were at risk of crankwalk. Mitsu cheapped out on the thrust bearing which caused the problem. after 96 they fixed the issue. all 95-96 owners have to do is replace their thrust bearing and the motor should be fine.

[98GSXdude]

:lol:

http://i27.photobucket.com/albums/c152/awdaddiction/crankwalk.jpg

[dufflebagboyz]

my 7 bolt is running very strong and nice.. only 105k though.. but its all good i always got a 6bolt swap waiting to happen =]

[gtsiawd96]

I have glanced over that before, but never entirely read it. There theory makes sense. The only noticable difference was the oil squirters construction, location and place where the oil squirters gets its oil supply from.

I love the people who say they have no crankwalk. But they have never actually got the dial indicator and accurately measured what is in spec of (.05-.18mm). I will guarantee you are out of spec or very close to being out of spec. I drove on my last 7 bolt and it was 1.8mm of endplay!! Thats 1,000 percent more endplay that the highest allowable specification at 185k miles. Still going. Just changing the thrust bearing will only prolong the inevitable. If the thust bearing is not being properly feed the right amount of oil/pressure. A new bearing will fail again.

[laser92dsm]

:lol:

http://i27.photobucket.com/albums/c152/awdaddiction/crankwalk.jpg

My friends always bug me with that pic :mrgreen:

[Fabian]

my 7bolt has a 133k miles on it with 14b turbo, 510 injectors, intake, full exhaust, 16psi, no emissions, FMIC, evo fuel pump and some others but all stock drivetrain. No signs of crankwalk yet. Of course I havent measured the endplay yet cause I dont know how to. But the car runs good and strong! I've definitely been thinking about replacing the bearings and thrust bearing though just to make sure.

[1000whpTSi]

I have glanced over that before, but never entirely read it. There theory makes sense. The only noticable difference was the oil squirters construction, location and place where the oil squirters gets its oil supply from.

I love the people who say they have no crankwalk. But they have never actually got the dial indicator and accurately measured what is in spec of (.05-.18mm). I will guarantee you are out of spec or very close to being out of spec. I drove on my last 7 bolt and it was 1.8mm of endplay!! Thats 1,000 percent more endplay that the highest allowable specification at 185k miles. Still going. Just changing the thrust bearing will only prolong the inevitable. If the thust bearing is not being properly feed the right amount of oil/pressure. A new bearing will fail again.

Thank you! Could'nt have said it better myself. I think you were the only one who actually read that far into it.

I've worked in my uncles machine shop for the last 15yrs.We've done some research in the past on 7 bolts and decided it was not worth our time.However I gotta' give it to the old man (my uncle) he nailed it on the head when he said it was due to an oiling issue......over 8 yrs ago!

[1000whpTSi]

Heres another informative little page.
http://www.scribd.com/doc/4570538/Mitsubishi-4G63-4G64-Engine

[gtsiawd96]

my 7bolt has a 133k miles on it with 14b turbo, 510 injectors, intake, full exhaust, 16psi, no emissions, FMIC, evo fuel pump and some others but all stock drivetrain. No signs of crankwalk yet. Of course I havent measured the endplay yet cause I dont know how to. But the car runs good and strong! I've definitely been thinking about replacing the bearings and thrust bearing though just to make sure.

I shouldn't have made a complete blanket statment in saying every 7 bolt is out of spec. But most 7 bolts that have heavy clutches installed are out of spec. Putting in new bearings is a good idea if your just trying to be proactive to save an already failing 7 bolt or just wanted to get a good idea of what your current thrust bearing is looking like. Pulling the T-case if you have one and the oil pan down is not very hard to do. Buy a new set of main bearings. Pull the main girdle off, slid the old bearings out, clean the backsides of the bearing surfaces off nice and clean and slide the new ones in.

[BlackBulletTSi]

i love this writeup, read it not to long ago myself