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Discussion Starter · #1 ·
Well guys, I pulled the oil pan off the 396 last night -- bearing material everywhere. Here's what else I found in there:

Those bolts are supposed to secure the oil pump pickup to the pump. You can see the bolt holes just in front of the pickup tube in the pic.

So here's what happened: When the pan hit something (a block of wood on the road I think) it smashed the pan onto the oil pump pickup screen. Even though it didn't get blocked enough to cause low oil pressure in normal driving, it probably starved the bearings when I went WOT. It dislodged the pump so much that it sheered off the two bolts securing the pump pickup.

I'm not sure if the copper looking shavings on the pickup screen are the the backs of the bearings or perhaps what's left of the nuts that went with those bolts. I couldn't find any nuts and the holes in the pump weren't threaded. Anybody else have any ideas that that could be?

So my suspicions about the big oil pan dent being the cause were correct. I would take this as a big warning to those running the Moroso pan. It only hangs about an inch lower than the stock pan, but obviously it's just low enough to be a problem.
 
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Discussion Starter · #2 ·
Hey Ron,

Thanks for the heads up. It would drive me crazy not knowing why something happened like that.

It just goes to show you that no matter how careful you are, something can alway happen.
 
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Discussion Starter · #3 ·
I could swear that bolts holding the pump cover (and in your case, the pickup bracket) just thread right into the pump housing. If you say that the housing is not threaded, either someone torqued them down too tight and stripped the housing, or someone has modified the pump to have through bolts with nuts. Those bolts do look pretty long to just screw into the housing. :confused: What do the other 2 bolts do?

My personal opinion is that you could just as easily have a coincidence here. The dented pan may or may not have contributed to the engine failure. As likely, the pickup could have just been installed incorrectly, letting it rest against the bottom of the pan when it failed and you just happened to notice that the pan was externally modified when investigating the failure. It's tough to tell from the pic of the dented pan exactly how far the metal moved (you also need to know the original clearance). I also can't tell if there is an impression of the pickup in the dented area, which should be there if the pan hit the pickup hard enough to make it break something inside. Those pickups are pretty tough compared to a stock style pickup because of the angle and thick bracketry. I would first be trying to find out why those bolts came out, and not worry too much about the dented pan other than popping it back out.
 
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Discussion Starter · #4 ·
Scott,
You're right -- the bolts don't require nuts. I went to Summit and looked up the P/N for this Moroso pump. Here's a pic:


So I must missed seeing the threads in the pump. I'm confident that whatever dented the pan smashed it into the pump. The bolts are clearly sheered off, the pickup tube is misaligned with the pump, and the pan is caved in all around the bottom except where the pickup tube resides. Also the pickup comes from Moroso already installed/assembled on the pump (and I bought it new) so I know that wasn't a problem.

Now my question is what the heck are the copper/brass looking shavings on the pickup? Is that part of the bearing backing plates? Those are *shavings*, not bearing sludge (although there's plenty of bearing sludge everywhere as well).
 
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Discussion Starter · #5 ·
Ron,
Looks worse than I thought :eek: Give me a call tonight and give me the skoop. Let me know when you are ready to take the 396 rotating assembly to the machine shop. We will let Certified pay for the transportation(work van) :D
i'm glad I wasn't there to see this.
We will get up and running agian better than ever. I have faith in our abilities.

Frank HVY SS
 
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Discussion Starter · #6 ·
Sorry then, I didn't see that the bracket holes were misaligned or the pickup was bent. You say the bolts were sheared off...the 2 perfect looking bolts you are holding? :confused:

Anyway, if the is the case, then the pan really did sustain much more damage than is visible in the picture in the other thread. There should be a pretty good impression of the pickup in the bottom of the pan in this case. If so, I can see where the pan caused the pickup to fail.

The copper is probably bearing material. It doesn't take very long for the bearing to unravel when they are starved. As a previous suggestion, inspect everything very carefully. Mag the crank and all bearing bores that showed any bearing damage, even if they are not discolored. When the bearings are shredding like that, they usually push the metal around and damage the bores more than you can see. Every piece of that mill is going to have to be examined and cleaned thoroughly. I feel for you :(
 
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Discussion Starter · #7 ·
<BLOCKQUOTE>quote:</font><HR>Originally posted by Scott Knight:
Sorry then, I didn't see that the bracket holes were misaligned or the pickup was bent. You say the bolts were sheared off...the 2 perfect looking bolts you are holding? :confused:
<HR></BLOCKQUOTE>

Hi Scott. They did look like they sheered. You can kind of see it in the above pic on the bolt on the right. The end of the bolt doesn't taper and the bottom surface is angled and has two "faces". Of course I'll look more closely at it tonight. I really just pulled the pan and took a quick look last night.

There is another good possibility. Perhaps the movement of the pan/pickup didn't sheer the bolts, but just pulled them out of the threads. That would make sense because I didn't see any threads in the pump housing last night. Also if they did sheer from the movement of the pickup, they didn't do it in an intuitive spot. You can see the misaligned bolt holes in the first pic, but the bolts go in from the top relative to that pic. That means that they should have sheered at the bolt head, not the bottom.

So anyway, perhaps they were pulled out and the bolts got hit by the rotating assembly after they were loose and sheered the tips off.

I'm glad to hear that copper/brass colored shaving are indeed that bearings. I was hoping to hear that.
 
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