Snapping A Crankshaft

[vspecR]

hey guys,

i want to know what are the usual subsquent events when a crankshaft is snapped? rods break? bearings? pistons? all gone too?

the car im about to buy had snapped a crankshaft and required a full rebuild, its all been fixed now, but im just curious as to what happens when it snaps? what will need replacing and repairing? this question is in relation of a rb26, not that it should make a difference.

i asked this qn in a thread before but i think my title was not appealing enough to attract attention and repsonse.

cheers guys

Edited March 3, 2011 by vspecR

[N1GTR]

The only way you will know for sure is to pull the motor down and inspect if a crank snaps or something else goes wrong inside that serious.

Have you got a receipt from the rebuild?

[N1GTR]

Oh also you'd want to get the car cheap given that damage.

Crank $1300

Rods $1000 for decent ones like Argo

Pistons $1300

Oil pump (N1) $300 odd

Water pump$200 odd

Timing belt $100

Bearings, machining, assembly etc with stock bolts depending on where you go start around $4000 and R and R.

Hope that helps.

[vspecR]

Thanks Steve, it does help

No the previous owner of the car lost the receipt, but the workshop that did the work said the bill ended up to be around the 17k. does that sound about right?

but they cant remember exactly what they replaced as it was over a year ago. i know they replaced the shaft, rods, rings and piston and turbos. if an engine goes would the turbos get damaged too?

[N1GTR]

Turbos may have been ceramic stockers and replaced cause they're pretty much useless on a built motor. Or maybe something from inside the motor went through them - who knows

17k sounds right, there must be some decent bits on there now for that money

[simpletool]

Wondering why he didn't just buy an RB26 crate motor.

[t_revz]

amazes me when people spend this much money on something and cant even keep the receipt in a safe place.

[N1GTR]

Wondering why he didn't just buy an RB26 crate motor.

Cause then you're back at stock and stock sucks!

[MrStabby]

amazes me when people spend this much money on something and cant even keep the receipt in a safe place.

Yeah I find that hard to believe. Since having the receipt is so important when selling the car, you'd have to be a retard not to hang on to it.

OP - will the workshop provide a copy of the receipt? Shouldn't be a problem as they have already confirmed verbally that they did the work. If not, I'd assume there is no build and you are buying stock, and work out the value on that basis.

[vspecR]

The price this GTR r34 is going is basically the price of a stock one. so anything performance part in the car is just a bonus.

I dont know why the workshop hasnt got the recept either, but they have gone out of their way to trace the suppliers the some parts numbers for me, so i dont want to hassle them too much.

this is what the tuner/builder told me:

the owner had a stock engine and turbos, with just a boost controller. he decieded to run over 25psi and eventually snapped the crankshaft

he then rebuilt it using forged pistons and rods (not much detail and he coudlnt rememeber)

after he rebuilt it, they keep the ecu and set the boost contorller to 12psi.

that was the last time he saw the car lol.

anyways to me, the owner is basically a bogan that works up in the mines that earns too much cash and know literally nothing about cars. When i asked him about the build, he just said, i dont know, i just knows its FAST AS f**k. lol

so i asked for the builder/tuners name as i couldnt get anything info off the owner.

thanks guys appreciate your opinions

[Bronx]

25psi and snapping a crankshaft???? thats a pretty hard thing to do. unless you had some very bad oil problems. usually would be a fked bearing, or melted/broken piston. the crank is most likely going to be the last thing to snap

ive gotten some cranks strength tested, and most of them snapped after about 700hp and 700nm tourque.

(BMW, VW and Audi cranks ive gotten tested) so nothing jap. but these were from the 1.8l engines too

just make sure you can get a receipt, or its stock. no proof no purchase i guess

or just offer him 5k below that price and just buy yourself a second hand motor and swap it out as a just in case, if its already going for that cheap

[MrStabby]

The price this GTR r34 is going is basically the price of a stock one. so anything performance part in the car is just a bonus.

I dont know why the workshop hasnt got the recept either, but they have gone out of their way to trace the suppliers the some parts numbers for me, so i dont want to hassle them too much.

this is what the tuner/builder told me:

the owner had a stock engine and turbos, with just a boost controller. he decieded to run over 25psi and eventually snapped the crankshaft

So the stock turbos survive at 25 psi but the crank doesnt? WTF? Too many weird and convoluted stories with this one - my dodginess alarm is going off. Personally, I wouldnt buy it.