Well my small shop i own with my partner, had our good buddies 2004 Evo 8 come in to get fixed up. * Car only has 18k miles as well*

Car was parked 5 years go after losing boost. Finally we pinned it down to a plugged cat converter. wierd. Customer bought all new turboback, intake and some others goodies. Everything was installed, ran like crap so obviously we treked the few miles to AMS and got it all tuned. Car drove great then started to have clutch issues.

long story short, come to find out while diagnosing a no start after doing a new exedy clutch, that the crank is moving in the block. you can visually see the crank pulley move when depressing the clutch. thus it took out the crank sensor because the sensor wheel had enough movement to clip the crank sensor. so the car just keeps eating crank sensors and wont run.

so the car needs a new shortblock.

My question is Ive been reading and talked to a few shops as well, and people are stating that if you are the " lucky one" to get crankwalk, that the block is not re-usable?

Im kind of stumped as to why the block and crank in the car cant be re-used? I used to work in a engine shop, and would see all kind of motors blow,break or whatever and the block and crank where still able to be used in the rebuild... We thought about tearing it all down, doing all new bearings and having the crank remachined, which would be the least expensive route for him. Or do we have to find a good stock shortblock, or bare block? he doesnt want nor need any 2.3L big turbo motors.

Just looking for some info if it is possible to still re-use the stock block and parts or as to why is not able to be rebuilt?

Thanks yal!

 

Usually if you get crank walk the cause is excessive wear in the thrust washers and they often spin and cause irreparable damage to both the block and the crank surface where the thrust washers ride. The washers are supposed to seat in the block and the crank rides on the oil, when the crank makes contact with the washer surface it quickly "wipes" the face of the washer and shortly after spins when it should not be spinning. I've only seen this in one Evo so far. Sorry for your bad luck.

Josh

 

It sounds like most of your information is coming from or is carryover from the DSM crowd. The seven bolt engines in those cars, once they crank walked you could fix them but they just crank walked again. If anyone ever figured out for certain why this was they never told me.

Anyway, supposedly, the Evo 8 engine has all of this fixed. I'd give the block a good look over before deciding to pitch it.

 

thats what i was thinking as well, at least check it out.

Im guessing we caught it pretty early. Cars had maybe 500miles MAX put on since it was pulled from the 5 yr hibernation.

 

what kind of clutch. I had a pretty reputable mechanic hypothesize that a pretty agressive clutch could cause this as wel.

 

http://magnusmotorsports.com/tech-ar...ankwalk-theory

interesting read about crankwalk, not sure if it applies to your situation

 

very unusual for a later type block to do this what centre bearing was in it ??? separate thrust washers ??

 

Since crankwalk on DSMs is full of half beliefs, missinformation, and possibly a little mysticism no one really knows the 100% root cause. What is known is that if a block crankwalked beyond 5-10k miles (Before that is due to assembly or machining errors) then replacing the crank and bearings is probably not addressing what caused it in the first place.

Through out my 12 years with DSMs Ive read lots of thread titled "crankwalked again" or along those lines.

Im of the mindset that if you got true crankwalk, then something is a little off with that block. It can happen to any motor, in fact I have a 167k mile 6 bolt that was completely stock from my GVR-4 with nasty crankwalk. So if it has real crankwalk, replace the shortblock.

 

Umm, I think you are about an order of magnitude off on those measurements.

I don't recall the evo's specs but I think DSM 4g63s are something like 0.008-0.017". 4mm is 0.157" and is far outside normal thrust play, ie not even close to a limit.

 

my all data shows .011" is max play in crankshaft movement recorded from a dial indicator.

car had a ACT2600 in it first time.

whats interesting is back in 05' when he had the clutch done the shop that did that clutch told he had crankwalk issues already then. he then forgot about any of that over the 5 years until we found his posts on here from 05.

its just odd we got the car running and back together and ran strong and good, put down 270hp for a intake/exhuast/bov/MBC car. sounded about right. then the clutch started having bad engagdment issues. so he did a exedy stage 1 we just put in, and upon start up we threw a CEL for no signal from crank sensor.

yanked that out to notice the signal tip worn off. so the car obviously has too much crankshaft movement as that disc is pushing out when depressing the clutch and clipping off the tip of the sensor.

just looking on info as to why really nothing could just be rebuilt but im uderstanding now. the Evo tech at a shop also spoke about how if it happens early like this is it could because of manufacture defect for the most part.


customer/buddy just looking to not have to dump another like 3k+ in the car when all he wanted was a few goodies and to just drive it as it was. So thats why we expressed rebuilding the current one but sounds like it wont be possible.

 

Apologies 0.05 to 0.25mm limit 0.40mm from wsm

 

Makes more sense. Values correct, magnitude a touch off

 

Tell him to sell it, if he can't afford to fix it. He can get a good chunk of change for a '04 with 18k miles.

 

Check thrust bearings first before trashing the block.

 

the thrust bearing is the issue, we already know that.

but from what ive read and talked with people on , and like posted above, the washer i guess turns in the block and cuts the block and damages it. thus putting in a new one would just result in the same problem down the road.

Moneys not an issue, if he wanted a crazy built car he could pay AMS to build whatever he wanted. he just wants a nice quick daily driver, so he can sell his junk *** GTO.