CRACKS inside 3.0 Block???

T77911S · 01-19-2009, 12:54 PM

i just bought this 82 3.0 engine. i pulled the oil sump cover off and noticed these cracks. are these a common problem? can they be welded or are they nothing to worry about?
they are on the left side, (1,2,3)

fireant911 · 01:33 PM

T77911S,
This looks like veining or finning. The mold appears to have developed a crack - which is not too uncommon in the foundry business. Look closer, the cracks appear to be raised rather than recessed into the casting (run your fingernail over the suspect surface).

edit: A pencil lead over the surface may work better to determine if it is veining/finning or the dreaded crack. In close re-examination of the picture, my money is on the veining/finning (this comes from ten years experience in foundries).

Porsche_monkey · 01-19-2009, 01:36 PM

I had a 915 case I was absolutely sure was cracked. It turned out to be veining as Daryl G suggested.

You should be able to inspect the upper 'crack' where it ends in the casting window. If it has any 'depth' it needs to be repaired. I would guess it is just on the surface.

T77911S · 01-19-2009, 02:50 PM

here is another angle.
should i try scraping some of the metal away to see how deep it is?

fireant911 · 03:26 PM

T77911S,
After seeing the second picture, I am very confident that the earlier prognosis (fins or veins) is indeed correct. The cracks are clearly raised, therefore you simply have a case of a small bit of excess metal... which, of course, is much better than the other way around. I would not worry about doing anything with this area. Sleep well knowing that the metal integrity is completely in place.

edit: cracks like this often appear on molds. It is very common in green sand molds and can occur for a variety of reasons. Permanent molds, which the case was made in, are not immune to this cracking either.

T77911S · 01-20-2009, 03:03 AM

thanks daryl.
anyone have a 3.0 open they can look at. i would like to know if anyone else has these "cracks"

Zeke · 01-20-2009, 08:05 AM

Why not put some grease on the "crack" and file it? Lots of fancy files can be found that will file from any angle. You will know the story when you wipe up the grease/filings.

Porsche_monkey · 01-20-2009, 10:30 AM

Or emery cloth.

Nine9six · Nine9six's Garage

I'm gonna go out on a limb here...
How about some dye penetrant dye, followed by the proper dwell time, followed by a proper cleaning, and then a light spray of developer. Reverse capillary action will indeed settle the mystery.
Some call this the visual Dye Penetrant method of Non-Destructive Testing (NDT)
HTH

dshepp806 · dshepp806's Garage

Quote:

Originally Posted by Nine9six

I'm gonna go out on a limb here...
How about some dye penetrant dye, followed by the proper dwell time, followed by a proper cleaning, and then a light spray of developer. Reverse capillary action will indeed settle the mystery.
Some call this the visual Dye Penetrant method of Non-Destructive Testing (NDT)
HTH

I agree with this quantitative "limb" as Nine9six put it,...

.,.....a very informative thread, certainly had me doing my homework, just with the terminology used within everyone's observations,...good stuff...

Thanks for sharing.,..and feel free to "expound" on these terms..Pelican University loves great Authors/teachers/professors.....let the info flow, baby.

Best,

Doyle

emcon5 · emcon5's Garage

Mine had "cracks" them when I did my rebuild. I freaked out as well, but upon further investigation they were veining and are fairly common.