Has anyone seen or tried this crankwalk fix

[JEsse Thomson]

I saw this on another site. It's 6 or mor years old but when I got crankwalk it was immediately after I got head studs Installed and I was hoping for your thoughts cuz I am going to try it.

http://www.dsmtuners.com/forums/bolt-tech/8817-update-crankwalk-fix.html

[Brett Haviland]

Yeah thats a big read.

From reading it they think the main causes of crankwalk are

1) Bad quality meteralgy in the 2G blocks causing blocks flex wierd causing stress on the thrust surfaces.

2) Misalignment of the trust surfaces of the block from heavier torque on ARP head studs

3) Honing/line boring and line honing the block WITHOUT a torque plate installed (imitates a cylinder head being torqued down to the block)

4)Using precision machined/installed dowel pins/holes in the mains/girdle on the 7 bolt engines to eliminate missalignment  of the mains upon installing the bottom end.






Personally i think its a combination of Bad/cheap metal used in 2G blocks...  Increased thrust loads due to stiff Pressure plates....improperly line boring and boring of the cylinder block on rebuilds.


but its all theories... maybe its global warming??

[Amir Ali]

Yeah thats a big read.


Personally i think its a combination of Bad/cheap metal used in 2G blocks...  Increased thrust loads due to stiff Pressure plates....improperly line boring and boring of the cylinder block on rebuilds.

[JEsse Thomson]

I've just never seen this take on it I always hear about the oil squirter theories. In any case it can't hurt to try a little extra work to make it perfect. It made sense to me so I thought I'd share cuz if it's true everyone ought to know

[Jesse Veitch]

Warped and/or improperly machined 7-bolt cranks is a popular one too.

People building 7-bolt strokers with a new crank don't seem to have any problems, nor do the people with 7 bolt 4g64s with the same girdle.

If you CSI that shit the only variable is the crank.

7 bolt engine is a better design than the 6 bolt, mostly because of the main girdle. So a 7 bolt stroker crank is the best fix I think. Get more displacement and no crankwalk with a main girdled and ribbed block. 6-bolt swap can stick that in it's pipe and smoke it.

[GlenMartin]

Warped and/or improperly machined 7-bolt cranks is a popular one too.

People building 7-bolt strokers with a new crank don't seem to have any problems, nor do the people with 7 bolt 4g64s with the same girdle.

If you CSI that shit the only variable is the crank.

7 bolt engine is a better design than the 6 bolt, mostly because of the main girdle. So a 7 bolt stroker crank is the best fix I think. Get more displacement and no crankwalk with a main girdled and ribbed block. 6-bolt swap can stick that in it's pipe and smoke it.

i like this post........might stroker my motor now. ya me.

[JEsse Thomson]

The improper machining makes sense cuz it would explain why people like me ( I'm surer there's more out there) getting crankwalk after a head stud install and why some people get crankwalk after high kms.  I've never heard the cranks being machined improperly but it's likley 6 of one and half dozen of the other. I found a dowel kit at Mach-v so this is probably more of a common thing than I think.

[KevinBuckham]

I don't believe that 7 bolt 4G64s have oils squirters.  The primary symptom is the thrust bearing getting chewed away and Marco's impressions seem to be the most logical.  Between the 6 bolt and 7 bolt blocks the squirters are fed differently absolutely exposing the 7 bolt motors to low main bearing oil pressure in the case of a clogged squirter. 

It also seems that re-built three piece 7 bolt motors have less issues, but that could be simple hear-say with no real evidence.

Besides installation fuck ups, and the batch of bad 7 bolt cranks I really think the rest of the cases are oiling issues.  (Low RPM, pressure lost in in the main bearing feeds, clutch pushed in for start-up.)

[JEsse Thomson]

Of course that makes sense but the oiling dosent explain how mine personally walked immediately after my head studs. My thrust is toast it was a 98 block and was checked for endplay when it went in. It was ok. I literally drove it home and it kept stalling out. Maybe if there's anyone else with similar stoy they can chime in. Maybe a head gasket job perhaps or something else Maybe a clutch?

[Jordan Kruger]

I heard the best fix is to lose a bolt   

[JEsse Thomson]

Yeah but I've heard they walk sometimes also but that's pure speculation

[Amir Ali]

I heard the best fix is to lose a bolt   

The best answer to that Q.

[kevin derhouson]

out of curiosity before you changed your headstuds did you have "lifter tick"? :\

[JEsse Thomson]

I don't believe so. I had the car for only a month and that was 2 years ago. Thehead studs were put in cuz I had a head gasket blow and I chose to upgrade while I could. Apparently the guys at evolution checked it before they did the head gasket. It was ok. They did all thework on thecae from the previous owner

[KevinBuckham]

Of course that makes sense but the oiling dosent explain how mine personally walked immediately after my head studs. My thrust is toast it was a 98 block and was checked for endplay when it went in. It was ok. I literally drove it home and it kept stalling out. Maybe if there's anyone else with similar stoy they can chime in. Maybe a head gasket job perhaps or something else Maybe a clutch?

That's a *super* fast failure.  That seems very suspicious to me.  Something is missing here.  It's likely completely unrelated to your head studs unless someone installed the head studs with an impact wrench.  For it to start stalling out immediately after means the bearing already had been destroyed and had excessive end play.

Anyway we are second guessing several well known DSM shops that will see more 4G63 motor failures than most of us will ever see.  If we can't take their explanation for it, I doubt we can solve it.   Personally I've seen two walked 6 bolt motors, and never a 7 bolt.  (I know that isn't usual, and my sample set is small.)  There is a very big problem applying what you've learned from a limited sample set. 

-Kevin