Crankshaft not centered
#1
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Hi -
I had my clutch blow out and the flywheel too, this was replaced but there was a engine vibration that my tech said could be a bad flywheel. On opening he said that the crankshaft is not centered and that the engine replacement is the most ideal solution. Below are two images one of the crankshaft alignment tool that does not fit due to the crankshaft being not centered (there is a gap on the top and no gap below).
Is engine replacement my only solution.
Thanks
![](http://img27.imageshack.us/img27/5190/download1rj.jpg)
I had my clutch blow out and the flywheel too, this was replaced but there was a engine vibration that my tech said could be a bad flywheel. On opening he said that the crankshaft is not centered and that the engine replacement is the most ideal solution. Below are two images one of the crankshaft alignment tool that does not fit due to the crankshaft being not centered (there is a gap on the top and no gap below).
Is engine replacement my only solution.
Thanks
![](http://img27.imageshack.us/img27/5190/download1rj.jpg)
![](http://img27.imageshack.us/img27/6531/downloadxm.jpg)
#2
Parts Specialist
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what?
OK in order for that to happen the cradle would have to have shifted off...OR the crank is bent (more likely)
rotate the cranck and check again
if the motor runs my guess is that the cradle did NOT move
report findings
OK in order for that to happen the cradle would have to have shifted off...OR the crank is bent (more likely)
rotate the cranck and check again
if the motor runs my guess is that the cradle did NOT move
report findings
#4
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light weight flywheel / or stock dual mass?
for $15k I want to know more before I start throwing away a running engine - contact Jake Raby (google search him) start gathering info and tell that tech to hang on!!
for $15k I want to know more before I start throwing away a running engine - contact Jake Raby (google search him) start gathering info and tell that tech to hang on!!
#6
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Have him put a dial indicator on the sealing surface of the crank and rotate crank. He'll be able to see any wobble on the indicator.
Sounds like the crank got bent. Replacement is the standard fix.
Phil
Sounds like the crank got bent. Replacement is the standard fix.
Phil
#7
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I just spoke to him and he is checking, should have the answer in 15 mins. Is it as expensive to replace the crankshaft. According to him it sounds like they both cost the same.
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#8
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Sorry, this must be a huge bummer for you.
Phil
#9
Burning Brakes
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Unfortunately that is why the go-no-go gauge is used in RMS issues and they usually have to replace the engine if out of spec. Hopefully there is another solution, if not rebuilt eng's from Porsche or good Indies (Autusse Newport) and offer 1 and 2 year warranties.
#13
Drifting
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So if the crank is out of spec, (nicer term then bent!) what would cause this? Over rev? A bearing die and overheat a section of the crank allowing it to twist or distort?? Anyone?
#14
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so IF the crank is off center (and not bent) what happens is the seal will never seal. Turns out the cradle was most likely machined off center at the factory and was never caught. The tool designed to check concentricity is pretty simple to use and give a GO/NO-GO result. If the motor is deamed out of range by the tool it must be replaced. There is NO fix and even rebuilding it would require a donor motor to make it right...
The other thing that "could" be wrong is a bent crank due to the flywheel/clutch issue. In this case if the motor is continued to run the crank will frac. and the rear section with the flywheel /chutch most likely will saw thru the bell housing and leave the car needing a new motor AND transmission.
Well - the news is just wonderful today (and seriously to the OP I feel rotten for you)
A call to Jake raby will confirm this info and according to what I have heard, there is not much even he can do. i would imagine he knows a few tricks and might be able to coax you thru a thourough checking to issolate exactly what is the problem and lead you down the correct path.... but be prepared, there is an extreamly high likelyhood that your motor is toast and needs to be replaced
again, so sorry about the news
to answer above - the crack might have become damaged when whatever the OP called "clutch blow out and flywheel too" took place ?????
The other thing that "could" be wrong is a bent crank due to the flywheel/clutch issue. In this case if the motor is continued to run the crank will frac. and the rear section with the flywheel /chutch most likely will saw thru the bell housing and leave the car needing a new motor AND transmission.
Well - the news is just wonderful today (and seriously to the OP I feel rotten for you)
A call to Jake raby will confirm this info and according to what I have heard, there is not much even he can do. i would imagine he knows a few tricks and might be able to coax you thru a thourough checking to issolate exactly what is the problem and lead you down the correct path.... but be prepared, there is an extreamly high likelyhood that your motor is toast and needs to be replaced
again, so sorry about the news
to answer above - the crack might have become damaged when whatever the OP called "clutch blow out and flywheel too" took place ?????
#15
Drifting
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The crank and supporting bearings are held in a girdle or cage which is bolted into the crankcase halves. The crank can be pefectly true, yet due to machining tolerances and other issues, the crank may not be concentric with the RMS bore in the case. This is one reason there are RMS leaking issues.
The go/no go tool checks the crank to case concentricity to determin if a seal will adaquetly hold back the oil in the case. Seals are somewhat forgiving but not if variances are too great.
Another thing, with all the RMS issues, I'd bet that RMS bore in the case halves is not individually machined using the center of the girdle that will be used in that very case. If it was, the RMS bore would be on center with girdle, and there would be no concentricity issues.
The go/no go tool checks the crank to case concentricity to determin if a seal will adaquetly hold back the oil in the case. Seals are somewhat forgiving but not if variances are too great.
Another thing, with all the RMS issues, I'd bet that RMS bore in the case halves is not individually machined using the center of the girdle that will be used in that very case. If it was, the RMS bore would be on center with girdle, and there would be no concentricity issues.
Last edited by nick49; 05-13-2010 at 11:35 PM.