crankshaft crack detection

[philb]

just checking a crank before install for cracks anywhere in yorks or mansfield nottingham leicestershire ...or is it possible to do it yourself not sure of the techniques involved tbh
tia

 

[doubleboost]

Depends on what sort of crank it is.
If you hang it by a end web and tap it with something metal
It should ring like a bell
If it sounds dead and dull it will be cracked
Penatrant spray also works

 

[Moose McAlpine]

Drop it. If it splits in two it has a crack.

At least that's one method i've heard of..

You can use crack detection dye spray.

 

[8ob]

Magnaflux is just about the only home proven way of crack testing cranks.

Bob

 

[DAPPH]

Put a big magnet on one end after swiping it from end to end several times and spray it with magnetic crack detection fluid ( used to be red colour ) any cracks will show up as a fine red lines

 

[Ali]

Magnaflux is just about the only home proven way of crack testing cranks.

Bob

Home? Please explain, I looked into that for some gears and it was silly money (for my hobby purposes).

Edit: maybe I’m thinking of some other process

 

[Moose McAlpine]

Home? Please explain, I looked into that for some gears and it was silly money (for my hobby purposes).

Edit: maybe I’m thinking of some other process

It's £300+ i think.

 

[Screwdriver]

Problem with doing something like this yourself for the first time is the chance of a false negative. Just because you don’t find a crack doesn’t necessarily mean there isn’t one.

I’d be looking up local engine tuners, dynos, performance parts suppliers etc. They would know where to have a crank tested.

 

[gordon stephenson]

The proper magnets are laminated flexible yoke shaped and at a push rusty water will find any cracks, Wedgie that was a popular member worked in NDT, And at one time he was giving away lots of close to date cleaning fluid and lots of dye pen items,

 

[500e]

Dye only works with surface cracks, you can get sub surface problems.
We used do all steel cranks before use, surprising failure rate
Google Magnaflux

MPI Equipment

Magnaflux magnetic particle inspection (MPI) testing equipment is designed to be fast, reliable and high-value.

magnaflux.eu

hence the cost
Different use of name Brad

 

[ranchero]

Magnaflux is MPI

Magnaflux is a trade name they make dye penetrant equipment as well.
could just go over it with a magnifying glass as that's how i check any indications i find.

 

[Robert Weaver]

Colour contrast dye (red, with developer) is the entry level test it's good for small surface breaking defects if you've access and it's done properly (cleaning, application, patience, wiping, developing, cleaning). Fluorescent dye is more searching, it'll find smaller defects, but needs more kit. Magnetic particle does surface and can also reveal subsurface defects. It needs simple kit but is more difficult to interpret.

I've done red dye on valve stems to show cracks, easy enough to do.

A crank should be easy, if you can clean it well.

 

[Hitch]

Magnaflux is a brand, not a process.

They supply MPI equipment as well as FPI and LPI.

 

[8ob]

Plenty of huge tube vids on home/diy magnaflux, its a simple process. No doubt there will be a vid along any time soon .


Bob

 

[philb]

interesting thanks all i will have dig on ur suggestions and report back