[cobra513]

Looking for someone that has either done one of these or is very familiar with the process. Twenty some years ago when I went to School for auto tech we magnafluxed with a hand size magnet and the powder, a few years back the machine shop I was using (from an auto parts supplier) used the same technique when I brought in a couple of blocks to be cleaned and checked out. (they have since closed their machine shop). What I am trying to find out is where I can get the magnet or what size or style I would need, I found the powder but the parts house says I have to have an expensive electro magnet ($500.00 +) and I know for a fact the guy that did it at the machine shop had just a hand sized hand held magnet because we walked out to my truck and checked some common crack areas before even unloading it and the cracks showed up right away. Someone also told me recently that there was a liquid you could get to test them but they couldn't remember the name, I have a few blocks and several heads I would like to check before deciding what I'm going to do with them. Thanks for any info I can get.

[S10 Racer]

Not sure about where to get the magnet but the liquid type is what is called dye penetrant. The dye test is usually a three part step. First is a cleaner that you spray on suspecting areas then you spray on a developer and let dry. The dye should be sprayed on from the opposite side of the others because it will penetrate through the crack and show up behind the developer as a red mark or streak wherever it is cracked. The good dye stuff is pretty expensive though and not being able to do it correctly on say a cylinder wall, it may not be an accurate indication of anything. Normally after a block is hot tanked, cracks in a cylinder wall usually shows up white. Around my neck of the woods, a hot tank job is $40.00 and mag testing is $50.00. It may not be worth buying the equipment for just a couple blocks unless you were going into a business of building engines.

[racecar100]

Goodson sell automotive shop equipment...
http://www.goodson.com/

[CNC-Dude]

Originally Posted by cobra513

Looking for someone that has either done one of these or is very familiar with the process. Twenty some years ago when I went to School for auto tech we magnafluxed with a hand size magnet and the powder, a few years back the machine shop I was using (from an auto parts supplier) used the same technique when I brought in a couple of blocks to be cleaned and checked out. (they have since closed their machine shop). What I am trying to find out is where I can get the magnet or what size or style I would need, I found the powder but the parts house says I have to have an expensive electro magnet ($500.00 +) and I know for a fact the guy that did it at the machine shop had just a hand sized hand held magnet because we walked out to my truck and checked some common crack areas before even unloading it and the cracks showed up right away. Someone also told me recently that there was a liquid you could get to test them but they couldn't remember the name, I have a few blocks and several heads I would like to check before deciding what I'm going to do with them. Thanks for any info I can get.

The Magnaflux Company offers eqiupment and supplies for this process. Larger machine shops have a magnaflux machine specific for larger volumns of blocks,heads,cranks,etc. that is done by placing the part onto a supported fixture at each end so a large magnetic ring can be moved along the entire length of the part and be energized while soaking the part to be checked with an extremely fine flourecent powder mixed with equally fine metal particles in a mineral spirit bath. Then with a black light, the stresses or cracks glow and are able to be seen.

[cobra513]

Thanks for the info guys but as I said I remember seeing the guy at the machine shop do this with just a large (about hand size) magnet before we even unloaded it and I'm almost sure it wasn't an electro magnet. Has anybody seen this or have any info about what size magnet it woul take ?

[CNC-Dude]

I've see those also. I don't know how trustworthy those types are, especially if the block or heads are still greasy. I believe Goodson made a handheld one like you are descibing. I saw that someone had posted a link earlier to them so you might check them out.

[redsdad]

Looks like $500 might be a bargain.

http://www.goodson.com/store/templat...e0b1b485a186e8

Dye pen may be the way to go.

http://www.goodson.com/store/templat...e0b1b485a186e8

[cobra513]

I already checked them out, the one they have is a little bigger and again has to be plugged in (electo magnet). What I'm looking for is basically a strong U shapped magnet. As far as reliability, on these particular parts I have some suspect areas that I can't confirm one way or another and none of them had other symtoms but I would like to try to confirm before deciding what to do with these. One had upper valve train problems, one has minor imperfections and discoloring on deck from a blown head gasket. I would like to sort of pre check these as well as others in known problem areas and suspect areas. The one he used imediatlely showed a small 1 inch crank on a deck and another with a crack across the top of the lifter valley.

[cobra513]

Redsdad saw your post after I did the previous reply. That might work I'll have to give them a call and see. I'm still trying to track down the machinist that worked for the machine company that did my other blocks to see if he has any info on what he was using.

[redsdad]

I've done both. They each have their advantages and disadvantages. I was actually certified for a while in dye pen (low level cert - couldn't do Code vessels). IMHO, PT is messier but less cumbersome. Based on the cost and relative ease of use, I think I would go dye pen.