How to repair crankwealk?
Apr 12, 2008, 11:03 PM
#16
Speaks the truth!! Nitriding isn't cheap because the metal expands, and has to be milled after nitration, but worth it. Honda's cranks come stock like this and is the reason they're almost impossible to kill.
What causes crank walk? I've never really heard much about the subject until I got an evo (honda kid at heart). Sounds like it would be ****ty thrust washers...
What causes crank walk? I've never really heard much about the subject until I got an evo (honda kid at heart). Sounds like it would be ****ty thrust washers...
Apr 12, 2008, 11:07 PM
#17
Nitride treatment is chemical case hardening of the outer layer of the bearing surface. I'd be surprised if your client had a billet crank that, untreated, was harder than the case hardening layer formed by nitriding, but I sure like to learn, so if there's more to this story, please explain.
Apr 13, 2008, 12:11 PM
#19
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Just removed the oilpan and measured the freeplay. It was 0.047 inc (1.2mm) 
!
How i know that crank is useless? Is the only way to put new bearings and measure it again?
!How i know that crank is useless? Is the only way to put new bearings and measure it again?
Apr 13, 2008, 12:15 PM
#20
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What i have understood Evo 5 -> they don't share crank walk problem.
Which Evo engine's can i use and are they bolt on? Or are there other Mitsubishi model's which i can take the engine?
Apr 13, 2008, 06:23 PM
#21
Your original post stated that you here noises when you push the clutch pedal. That noise comes from the crank moving so much it pushes on the rods . the noise you here is the pistons being pushes sideways as they turn. thats why I told you from the beginning that you need a new crank. installing new bearings is a complete waste of time.
Apr 13, 2008, 07:17 PM
#22
|
|
|<------ damage
|______________|
(bearing rides here)
Take a look at your crank and you'll see the damage on the side -- replacing the bearings will not fix this. If it were a valuable antique limited production crank, they'd try to weld in the damage and then regrind the side face of the journal, but the grinding process is very difficult because of its location and the physical geometry of the grinding machines, which are made to grind the horizontal surfaces, not the vertical sides.
Often the block is also damaged in that area as well. That is why you will need at least a different undamaged crank, and maybe a block as well.
Apr 13, 2008, 07:24 PM
#23
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In 1998/99 Mitsu changed the thrust bearing to a 3 piece unit. This must have been done for a reason! In fact since this change I have seen very very few crank walk issues. If you are goiong to replace your motor make sure it is replaced with on that has the new thrust bearing design!!!! Dont waste your time on the older 2 piece thrust bearing motors.
Apr 14, 2008, 05:25 AM
#24
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with every engine known to man kind billions were built with the 2 piece main/thrust bearing and never had crank walk issues so I will never believe the bearing design was ever the issue. But almost all crank/thrust failures are do to machining and oil failure. The thrust is a very low volume low preasure oiling point in the engine to begin with and when you add a failing oil pump, lack of maintanance, poor grade oil, heat, and heavy clutch in traffic it will fail in good time.
Apr 14, 2008, 08:34 AM
#25
Crankwalk on IVs is very common. It is not common on the 5 and up due to design changes, so you are unlikely to gey a used walked engine. The newer the engine, the better the likely condition, so try to get one from an 8.
Apr 14, 2008, 01:17 PM
#26
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Yeah.............right, 
Please enlighten me as to how surface hardening the crank will help this guy stop eating the thrust bearings. I'm all ears. Nitriding is good for adding extra strength but it wont stop you from wearing into the softer bearing material. The crank could be made out of Kryptonite but if you've got something removing the lubrication from the thrust surface it's going to cause excessive endplay (crankwalk).
Perfect example- A customer of ours has a 706 ci Chevy motor with a $3500 billet crank, harder than any nitrided crank out there. He's put a number of passes on it in the last few years with no problems. He decides to change out the torque converter, it's not installed properly and it pushes on the back of the crank causing the thrust to be worn almost immediately. The point I'm trying to make here is that hardening the crank isn't going to stop the original poster's problem.
T-55; Like I said earlier, try to find out what is causing your issue and don't just treat the symptoms. You must identify the root cause of your problem and fix it or you will continue to have thrust problems. If you have any questions as to what could be causing it and how to remedy the situation, feel free to give us a call at the shop, 410-859-3269 or shoot me a PM.
Please enlighten me as to how surface hardening the crank will help this guy stop eating the thrust bearings. I'm all ears. Nitriding is good for adding extra strength but it wont stop you from wearing into the softer bearing material. The crank could be made out of Kryptonite but if you've got something removing the lubrication from the thrust surface it's going to cause excessive endplay (crankwalk).Perfect example- A customer of ours has a 706 ci Chevy motor with a $3500 billet crank, harder than any nitrided crank out there. He's put a number of passes on it in the last few years with no problems. He decides to change out the torque converter, it's not installed properly and it pushes on the back of the crank causing the thrust to be worn almost immediately. The point I'm trying to make here is that hardening the crank isn't going to stop the original poster's problem.
T-55; Like I said earlier, try to find out what is causing your issue and don't just treat the symptoms. You must identify the root cause of your problem and fix it or you will continue to have thrust problems. If you have any questions as to what could be causing it and how to remedy the situation, feel free to give us a call at the shop, 410-859-3269 or shoot me a PM.
. I am from Europe so it is litle bit big distance for your shop. Thanks anyway. But please give us all information about the crankwalk. I believe i am not going to be the last one who is going to deal with this problem.
Apr 14, 2008, 01:20 PM
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Apr 14, 2008, 01:25 PM
#28
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What i have learned wiring isin't same in Evo 4 and Evo 5, but is all "hardware" same?
Apr 14, 2008, 04:13 PM
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I believe it it caused my poor engineering by Mitsubishi . I am from Europe so it is litle bit big distance for your shop. Thanks anyway. But please give us all information about the crankwalk. I believe i am not going to be the last one who is going to deal with this problem.
. I am from Europe so it is litle bit big distance for your shop. Thanks anyway. But please give us all information about the crankwalk. I believe i am not going to be the last one who is going to deal with this problem.
