Parinoid About Crankwalk

[Sernadaburna]

i am not sure if i am paranoid or just worried but i bought a 7bolt jdm motor for a $1000 from jersey. i installed the motor and did a compression test yesterday and the compression in all cylinders were 170 throughout. i was wondering is it possible to still get CW can someone please relieve me of my stress thanks rich

 

[erald01]

You should be fine as long as you keep up with the maintnance of the car, especially oil. A lot of people on this formu will tell you all kinds of different stuff, but the CW are not that common. Also if you want to be sure get the thrust bearing and crankshaft endplay checked by your mechanic.

 

[supercarbuilder]

like erald01 said run good oil. And I know that if you rebuild it you can drill out the oil ports that go to the thrust bearing to get more oil there. many think that was the main cause of cw. and if you can help it don't use a heavy pressure plate clutch setup. more side to side pressure on that bearing prematurly wears it down which could lead to early cw. also, how many miles are on the engine?

 

[dsmtalontsi95]

I wouldn't worry about it, people say it happens around 75k-100k and if it is fairly new you'll be fine for now. Your more likly to spin a rod bearing then to get crank walk.

 

[dsmsucks]

I notice when this topic come up, 2g guys always talk about it being overrated. Almost every mouth somebody is saying their crank walked.

 

[Sernadaburna]

The Motor Has 35k On It And I Have A Findaza Flywheel And Act2600 Clutch. Other Then That Thanks Guys For Calming Me Down I Think I Am Going To Rebuild Another Motor And Make It A Stroker So I Dont Have Worry Or Get A 6 Bolt. Thanks

 

[1LE]

Most people blow up their motors from poorly executed mods rather than crankwalk People always write on the forum when CW happens, but they don't 'fess up to all the motors they've blown up themselves. Don't worry too much. I'd have no fear of putting a 2g 7-bolt back in my car.

 

[silver bullit]

Crankwalk is about as common as a honda running 10's on street tires

 

[keslerkaiyu]

Let me tell you about my CW issue. I never had it but thought I had it because of all the overated BS I 've read over the year.

I was driving one day and made a hard left just like everyone said it could occured after doing, right? All off a sudden the Clutch stayed on the floor and wouldn't come up. The car had about 65K miles on it.

Damn it's CW I said to myself. So being pissed off I never checked the car out, just let it sit.

Anyway I had a 6 bolt built by RRE and finally I intalled it in the car. This was about 2 years later. When I was putting the engine back into the car. I still have the same problem.

The clutch would not come up from the floor and would not hold any pressure no matter how much we bled it.

There was a small seal inside that needed to be replaced. That's all it was that caused me to lose pressure in my clutch 2 years ago.

The lesson here is that If you think you're gonna have CW, you will.

anyway I probably have a good 7 bolts laying in the garage with 65k miles on it if anyone is interested.

 

[tlikethedrink]

if its an early 7 bolt(you didnt say what the motor came off of) you dont have to worry about CW.
i would worry about more common engine killers... just have to have a proper running engine before you start tryng to make big HP numbers.

 

[Red97Eclipseboy]

Let me tell you about my CW issue. I never had it but thought I had it because of all the overated BS I 've read over the year.

I was driving one day and made a hard left just like everyone said it could occured after doing, right? All off a sudden the Clutch stayed on the floor and wouldn't come up. The car had about 65K miles on it.

Damn it's CW I said to myself. So being pissed off I never checked the car out, just let it sit.

Anyway I had a 6 bolt built by RRE and finally I intalled it in the car. This was about 2 years later. When I was putting the engine back into the car. I still have the same problem.

The clutch would not come up from the floor and would not hold any pressure no matter how much we bled it.

There was a small seal inside that needed to be replaced. That's all it was that caused me to lose pressure in my clutch 2 years ago.

The lesson here is that If you think you're gonna have CW, you will.

anyway I probably have a good 7 bolts laying in the garage with 65k miles on it if anyone is interested.

Damn that sucks!

But since your lack of detail, I must ask: what seal inside of what are you talking about? Just wondering.

 

[n55long]

what do you consider an early 7 bolt?

 

[keslerkaiyu]

Damn that sucks!

But since your lack of detail, I must ask: what seal inside of what are you talking about? Just wondering.

I'm not sure, but it was an "O" ring actually. it was dry rotted and would not hold pressure.

I wish I could tell you the name but not being a Mechanic, I can't even begin to say what it is.

 

[Red97Eclipseboy]

I'm not sure, but it was an "O" ring actually. it was dry rotted and would not hold pressure.

I wish I could tell you the name but not being a Mechanic, I can't even begin to say what it is.

I assume it was in the master cylinder?

 

[keslerkaiyu]

It's the portion that move back and forth when you step on the clutch. At one end of it, there is an "O" ring. My friend and I drove around to all the parts store looking for it.

But the good thing is that I wanted to do a 6 bolt swap anyway, and I dont think my wife would've approved unless she think the car was dead

 

[Red97Eclipseboy]

It's the portion that move back and forth when you step on the clutch. At one end of it, there is an "O" ring. My friend and I drove around to all the parts store looking for it.

But the good thing is that I wanted to do a 6 bolt swap anyway, and I dont think my wife would've approved unless she think the car was dead

Oh, okay. Yeah, it sounds like it was in the master. Good to have a 6-bolt anyway!

 

[Sernadaburna]

The motor came out of a 95 gsx with about 35,000 miles i guess from 95-97 would be earlier 2g and 98-99 would be the more common cw motor.

 

[Defiant]

On this site, you'll be better-off to worry about your spelling, rather than crankwalk.

 

[turboglenn]

Crankwalk is about as common as a honda running 10's on street tires

+1 as far as i've seen anyway. I've "heard" about tons of people getting it, but every car i've ever checked around here was fine. Mine was near the service limit for factory spec for most of it's life untill it died of too much boost and too lean of an AFR at 95k Miles.

You'll be fine. From what i've heard, it was more common in the 7 bolts that were built at the plant here in the US. My general concensus is that it isn't hardly common at all on any of the motors produced in japan. My reasoning for this other than just by head count of what motors did and didn't and where they originated. Is that the US made motors had to have every crank journal bearing individually matched with a block casting # and then the size of the journal ( i think there were either 16 or 24 diff bearing sizes for 7 bolt US cranks). And while this should lead to better QC of tolorances, i think it lead to more out of tolorance bearings in some journals putting extra load on the rest , some of which being teh thrust bearing since it takes loads from 2 axi

EDIT: For those who believe that crank walk is ONLY a late model 7 bolt issue. This is supposedly not true according to Robert H. at RRE. He told me that he's seen a few 6 bolts crank walk. But i've never heard anyone else say that so take it for what it's worth. I'll take it as "hearsay" untill i see it personally.

 

[romeen]

The motor came out of a 95 gsx with about 35,000 miles i guess from 95-97 would be earlier 2g and 98-99 would be the more common cw motor.

The other way around. CW was most common on motors made between late 1995 and mid 1997, although all 2G's were susceptible. For some reason the 1G 7 bolts didn't have this issue.

 

[TSG59_Steve]

The other way around. CW was most common on motors made between late 1995 and mid 1997, although all 2G's were susceptible. For some reason the 1G 7 bolts didn't have this issue.

I'm sick of seeing all this speculation and hear-say on which years did what, blah blah blah. Show me some numbers or some kind of proof. Otherwise I think you're all just full of it.

Romeen, I'm not pointing you out directly. Rather everyone that claims that certain years are more prone to crankwalk then others. I'm tired of it. I haven't been in this game very long but in the 2+ years I have been, all I've heard is speculation. Not once have I seen a SINGLE case of real crankwalk. Spun bearings? Hell yeah, a lot of them. PERSONALLY my 95 and two 97's have spun bearings. I'm not saying cw doesn't happen, but it's a hell of a lot more rare then spun bearings. Some people say the spun bearings are because of cw... maybe, but guess what, I've seen two BRAND NEW Subies spin bearings. Imagine that huh?

And if you do have some kind of proof, even of the difference b/w 95/96 motors and 97-99 motors throw it up. I don't mind learning something. I've heard a lot of talk about it. Never any proof.

/rant.

 

[2gGSX]

I recall reading on here a LONG time ago about an alternate theory of crankwalk. It dealt with the actual composition of the 1g 7 bolt and 2g 7 bolt blocks. Supposedly the 1g 7 bolt and early 95 engines had a higher concentrate of either iron or nickel, but the later 7 bolts did not. This actually allowed those blocks to physically "flex". The actual writeup was very intricate and it's a shame that I haven't been able to find it again.

Another fact that points to this was brought up by Hal Landry recently:

As far as I know, the only difference is to the lower cap/girdle assembly.

It's NOT machined on the side faces of the cap for the #3 bearing.

That is so the it can retain the thrust pieces of the bearing. No thrust surface on the lower half of the #3 main.

Yes, that means the motors do indeed use 180 degree thrust bearings.

This design (imho) defines what the factory thinks causes crankwalk, and it's not an oil supply issue.

Hal

Since the design divorces the thrust surface from the crank bearing I would extrapolate that the root cause of crank walk is actually block "flex" or warping.

The design lets the thrust plate actually "float".

If people could get sample filings to me of various engines, I might be able to get someone to run a spectrophotometric determination of alloy concentrations within the various engines. I would need filings of a 1g 7 bolt, and an EARLY 95 (e.g. 94 build date) 7 bolt, and I could provide the late 2g 7 bolt sample.

 

[romeen]

I'm sick of seeing all this speculation and hear-say on which years did what, blah blah blah. Show me some numbers or some kind of proof. Otherwise I think you're all just full of it.

Romeen, I'm not pointing you out directly. Rather everyone that claims that certain years are more prone to crankwalk then others. I'm tired of it. I haven't been in this game very long but in the 2+ years I have been, all I've heard is speculation. Not once have I seen a SINGLE case of real crankwalk. Spun bearings? Hell yeah, a lot of them. PERSONALLY my 95 and two 97's have spun bearings. I'm not saying cw doesn't happen, but it's a hell of a lot more rare then spun bearings. Some people say the spun bearings are because of cw... maybe, but guess what, I've seen two BRAND NEW Subies spin bearings. Imagine that huh?

And if you do have some kind of proof, even of the difference b/w 95/96 motors and 97-99 motors throw it up. I don't mind learning something. I've heard a lot of talk about it. Never any proof.

/rant.

The info that I gave is based upon conversations with a tech at a local Mitsu dealership (Rey Reece Mitsu here in Portland) who has apparently gone over the service records to look for a trend, as well as the results of an internet survey (which I'll try to find and post up), in addition to something on the RRE website that I had read which I will also try to find and post up.

As far as an actual, confirmed case of CW it happened to ME. It was confirmed upon tear down of the motor (after my car made an awful noise and just shut down in traffic one day).

Anyway, I don't blame anyone for being skeptical of something they read on the internet because you have to sift through alot of BS to get some accurate info. Like I said, I will try to find and post some of the info that I have previously seen.

 

[Defiant]

I still wonder if the full-girdle of the 7-bolt contributes to the increased thrust bearing failure rate over the "floating" thrust bearing web of the 6-bolt.

 

[97gsx_zeclipse]

I stumbled upon this information. I was just curious of the differences between the 1g vs 2g, and saw the percentage of CW and years they were in.

Model Guide: 1G vs. 2G Comparison - DSMtuners