The Top Mitsubishi Galant VR-4 Resource

Join the best E39A 1991-1992 Mitsubishi Galant VR-4 community and document your GVR4 journey.

  • Software Upgraded - Reset Your Password to Login
    In order to log in after the forum software change, you need to reset your password. If you don't have access to the email address you used to register your GVR4.org account, you won't be able to reset your password. In that case, follow the instructions here to regain access to the forum.

The damage caused by a loose crank pulley

BoostedAWD91

Well-known member
Joined
Mar 1, 2007
Messages
2,937
Location
Danville,Pa
damn man that sucks!! I know what will help ya though if you sell me that nice JDM front bumper to pay for you repairs /ubbthreads/images/graemlins/grin.gif
 

TRBODSM

Well-known member
Joined
Feb 4, 2009
Messages
278
Location
Northglenn, CO
Nice try guys, I pretty much have everything to do a stock rebuild minus rings and bearings. I am still going back and forth on doing a stock rebuild or just getting a daily and doing something a bit better.
 

Barnes

Well-known member
Joined
Feb 9, 2003
Messages
6,249
Location
Richland, WA
Best GVR-4 mod ever = daily driver. DO IT!
 

TRBODSM

Well-known member
Joined
Feb 4, 2009
Messages
278
Location
Northglenn, CO
This was my daily and didnt really give me any major troubles until now. I thought maybe I could of put a new head on there and have it running the day afer but seems like the damage was more than I imagined. If the valve wouldnt of broke it might of still been repairable but it is what it is.
 

damn that sucks.
i've seen that happen to a couple of 1G dsm's before. at least it igves you an excuse to put some fresh parts on it.
 

bazeng

Well-known member
Joined
Feb 6, 2003
Messages
2,520
Location
Melbourne, Australia
So what happened exactly?

The crank pulley bolt came loose which made the harmonic balancer come off totally?

Then the lower Tbelt gear on the crank slid out or something?

Sucks mate..
 
Last edited:

NateCrisman

Well-known member
Joined
Nov 22, 2008
Messages
2,054
Location
Blairstown, NJ
I had seen major Tbelt failures which destroyed the engine caused by BOTH the harmonic balancer coming off or the main crank pully bolt backing out.

A: the harmonid dampner crank pulley gets loose....wobbles a bit, cuts into the plastic timing case like butter and either slices of AC belt or chunks of plastic case get between the Tbelt and pulleys and cause the jump & carnage.

B: the main crank bolt backs out (the one that has the 1/2" square hole) and allows the crankshaft timing belt pulley to walk back off the crank and when it gets about halfway off, the key aligning the pully/crank will snap and allow the two to rotate..causing carnage.

Either way is bad mmmkkkk /ubbthreads/images/graemlins/rofl.gif
 

4thStroke

Well-known member
Joined
Oct 22, 2007
Messages
1,864
Location
Vancouver, WA
This happened to Brianawd when I was with him once. Lucky for him though, the piston only kissed the valves in one cylinder before the motor shut down.
 

Brianawd

Well-known member
Joined
Apr 18, 2005
Messages
2,117
Location
Portland OR,
Quote:
This happened to Brianawd when I was with him once. Lucky for him though, the piston only kissed the valves in one cylinder before the motor shut down.




I got really really lucky. It could have been really really bad.

I ended up tracing my crank sprocket bolt coming lose because of a leaking water pump. Water some how made its way into the treads and turned the blue loctit I used into past.
Then the crank bolt backed out and the sprocket got lose and slipped on the crank. Mine only slipped by 2-3 teeth because the keyway dug into the sprocket.
 
Last edited:

I almost had a similar catastrophe when I lost the oil plug off the oil-filter housing.
the motor still had the balance shafts in it at the time, well the balance shaft behind the crank pulley seized up from not having oil and stopped the t-belt which stopped the head from rotating
but the rotating mass of the crank kept going and it stripped all the teeth off the t-belt it had in contact with it. I was so lucky that it all happened at a point when all the valves were closed.

but like someone said, this does give you a reason to put some fresh parts on the ride. good luck to you.
 

fuel

Well-known member
Joined
Feb 23, 2009
Messages
2,165
Location
Toronto, ON, Canada
I think the biggest downfall with Mitsubishi DOHC motors is they aren't non-interference which would totally avoid catastrophic engine failure if the timing belt breaks or slips etc. Toyota and Honda and many others have tried to make most of their engines, DOHC included, non interference - especially the ones driven by a timing belt.
 

gmp

Well-known member
Joined
Apr 1, 2007
Messages
549
Location
Denver,co
oh man that sucks, i just killed a clutch slave today woohoo whitey's keeping it interesting...
 

curtis

Well-known member
Joined
May 4, 2003
Messages
11,892
Location
Clarksville TN
don't do the JSB thing start working on it now.
 

AnotherNewb

Well-known member
Joined
Apr 25, 2010
Messages
1,472
Location
Orlando, FL
Dbossman has a 2g GSX that the harmonic balancer seperated and let the acc. belts walk into the timing cover /ubbthreads/images/graemlins/banghead.gif, with less damage, it just cost him a head. Sorry about your luck... Good luck with the rebuild...
 

TRBODSM

Well-known member
Joined
Feb 4, 2009
Messages
278
Location
Northglenn, CO
Exactly what Nate said. The bolt holding the pulleys together came loose and the timing belt was only about half way on as you can see the marks on the timing belt. The body of the car held the harmonic balancer and it didnt completley fly off. When the harmonic balancer backed off it pretty much tore up the alt belt but didnt rip it off and somehow it seized. My powersteering was going out so I think that is what caused the alt belt to seize. With the sudden stop of the alt belt and the timing belt half way on it skipped therefore causing all the damage when a valve broke. I dont understand how it happened a year after the rebuild but its a Mitsu thing.
 

Quoting curtis:
don't do the JSB thing start working on it now.



Is this a "Do as I say, not as I do" type thing you are saying there? /ubbthreads/images/graemlins/grin.gif
 
Support Vendors who Support the GVR-4 Community
Boosted Fabrication ECM Tuning ExtremePSI Fuel Injector Clinic Jacks Transmissions JNZ Tuning Kiggly Racing Morrison Fabrications RixRacing RockAuto RTM Racing STM Tuned
Top