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Onefast99gsx
01-16-2005, 06:12 PM
Hello.

I don't really know much about crankwalk nor do i ever want to. I have a '99 GSX with about 80,000 miles on it. It's got a Fidanza flywheel and a ACT 2600 clutch. Can you tell me if my symptoms point to crankwalk. If not, what does the problem i describe seem like?

I got the car in late August from a respectable person. He told me up front that the tranny would need synchros so i just planned on doing over the winter. From about the point when i got it, it seemed to engage almost right off the floor, probably 1/2" or less even. That made if difficult when shifting. Often for 1st and reverse, you'd be better off shutting the car off and shifting to your gear and restarting the car up.

I got down under the dash and adjusted the master cylinder rod according to a vfaq. It does not take much at all. I would adjust it about a 1/4 turn out, retighten the nut.... So then it would be fine. It was disengage about 1 1/4 to 1 1/2" off the floor or about where it should be at. Well then after driving the car for 20 to 30 minutes the clutch would disengage WAY off the floor almost to the pedals idle position when your foot isn't on it. This would cause the clutch to slip very badly. So then you'd get under the dash, loosen the nut and turn the rod back in 1/4 turn so it engaged at around the stock position. Well then after the car sat for awhile unrun, it would engage off the floor again. This whole process would loop time after time. I rebled the system numerous times. I have the tranny out now. The flywheel, pressure plate and clutch disk all appear to be fine as i figured they would be. The clutch fork is also fine appearing. I figured that if it were any of the 4 things i just mentioned that it would do it ALL the time. Last night i took the slave cylinder all apart and showed it to a friend that's a mechanic. He didn't see anything out of the ordinary. The seal and piston looked good. Today I took out the master cylinder and took it apart. I really don't know how to tell if its bad or not. There is a rubber seal on each end of the pistona and they are both in tact.

Can someone please help me on what they think the problem might be? I would hugely appreciate it.

I show really no signs of crankwalk like the pedal sticking on a left turn or clicking noises, etc... However when my clutch is disengaging right off the floor i tend to have to take the tip of my foot to bring to pedal back in its idle position.

Thanks for ANY help!!!

AJ
01-16-2005, 06:19 PM
http://www.roadraceengineering.com/walkingcrankshaft.htm

http://www.magnusmotorsports.com/crankwalktheory.htm

http://www.prostreetonline.com/pso/pages/techtips/showarticle.asp?articleid=5

Justa few good reads with info.

Onefast99gsx
01-16-2005, 06:36 PM
Shit! According to some of that reading. I might have Crankwalk. I have the tranny completely out. I had a ticking sound before i parked it but i ran a can of the Mopar combustion cleaner thought the throttle body and the ticking went away. Is there any way i can check for crankwalk while the car is up on jackstands?

Thanks.

john
01-16-2005, 06:44 PM
Measure the crank endplay with a dial indicator. That is about the only way t check. QPR can do it and Elite may also be able to.

Onefast99gsx
01-16-2005, 07:04 PM
I have a dial indictator at our shop here. So i would basically take like a crow bar and go between the block and the flywheel and check for any variance in the dial indicator. Correct???

Onefast99gsx
01-16-2005, 07:08 PM
I know this isn't the wanted sections.... but does anyone have a 6 bolt for sale just in case? I would want the complete head and block.

Thanks!

1ViciousGSX
01-16-2005, 07:40 PM
It sounds to me like you never really got the clutch rod into adjustment correctly. 2g's will get a "ghost" pedal and pump up if the rod is too tight or the clutch/cruise switch is out of adjusment at the top.

Onefast99gsx
01-16-2005, 08:14 PM
Thanks for your input 1Vicious--- I can agree with you there. I never used a "proper" tool or method to adjust the clutch rod. When i sensed a problem, i would just loosen the nut and then turn the rod in or out about 1/4 turn.

I'll be heading home soon with the dial indicator to check for play. I pray! I just don't need this right now. I spend most my money on mods.

Can someone answer this. Let say i check and find out i do have CW. Can you take the engine apart and put in new crank bearings and it will be fine for awhile or does it physically ruin the block, crank and crank cradle? If i do have CW, i would like to do a 'get by' fix until late this year.

Thanks again!

1ViciousGSX
01-16-2005, 08:17 PM
From what I've seen, if it has crank walk, junk it. I haven't heard of anybody having success with a cankwalk repair.


Hopefully that won't be the case. If it is, I do have my old '99 7-bolt sitting around. 58k on it. No signs of crankwalk.

Onefast99gsx
01-16-2005, 09:34 PM
UPDATE: If got home and mounted the dial indicator on a magnetic surface. I put the needle on the outter most area of the replaceable section of the fidanza flywheel. I used a crow bar type tool and pryed between the back of the flywheel and the black. I would have been in a sense pulled the flywheel towards the passenger side of the car. I physically could not make the needle move any more than .002 to .004" at most. I think those readers derived from mostly flexing of the flywheel from pulling on it so hard with the crow bar. Now i did not try moving the crank towards the driver side of the car. Not sure how i could do that unless you pry between the block and the crankshaft pulley. If that's the case i'd need a 2nd person on hand to watch the needle while i pry on it.

You think things are looking good so far????

1Vicious- I hope i don't need that 7bolt block, but if i do, i will be calling upon you.

Thanks again.