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 Post Posted: Tue Nov 29, 2011 12:28 am 
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Yes, what Ken said.
Apparently I am not making myself clear, but at least Ken understood me. #-o

This is a block that I used in a different engine making at least 100hp more than the 414ci engine which just had the bearing problem. It never had any bearing problems with the higher power higher rpm engine. It ALWAYS had oil pressure loss in the shutdown ,,, same full depth pan on both engines.

Ken is also correct about the rpm of the current combo. Shift was set at 7200.

The current combo only had 2 passes where the pressure went low, my dragster has a lite.

Ken I don't think leaving it in gear in the shutdown is a big deal. The rpm drops off a lot as soon as the throttle goes back to idle. It's the way I've always done it.

Rick


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 Post Posted: Tue Nov 29, 2011 12:40 am 
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More pics as Don requested.

On another note I also verified the rod bearing from the other pic that gearhead asked about was actually in the correct half. The "upper" and "lower" marks are still visible inside the rod that was next to the spun bearing. The copper side on it was rubbing on the spinning and very flattened #7 bearing.

First is 2 pistons before cleaning the top. These are 7 (the spun bearing) & 5 on the right.
Image

Next is the right piston from the previous pic after wiping as much carbon off as a rag and wd-40 would clean. No sign of detonation on the pistons that I can see.
Image

Here is the #4 main saddle and cap turned over next to it. There is a little fretting that I hadn't seen before. Definitely visible in this picture. This main is closest to the spun #7 rod bearing.
Image

Here is #3 cap and saddle. No or at least very little fretting.
Image

Thanks for your input.

Rick


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 Post Posted: Tue Nov 29, 2011 2:05 am 
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In the picture of the 2 pistons with brown on them what is with the rings on the left piston. Are they dark from heat or what?


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 Post Posted: Tue Nov 29, 2011 7:26 pm 
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Rick,

I don't see enough of anything that would really point its finger ant any one thing.... Like you said no real signs of detonation on the domes. Not real bad dancing of the caps. imo any way.

I think the first thing I would do is recheck the balance of this combination. Not pointing any fingers of course. Just somewhere to start and confirm. How was this balanced,...50% 51% or 52%

btw,..I like the rounding of the corners around your valve reliefs.

Sorry for not being any more help. I have seen this same kind of thing in the past, way in the past [-( , so I can't remember what we found that cause it. But I do remember the #7 rod bearing looking like that. Why is the problem child usually the #7 hole anyway?

Don

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 Post Posted: Tue Nov 29, 2011 9:15 pm 
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want-a-be wrote:
I have seen this same kind of thing in the past, way in the past [-( , so I can't remember what we found that cause it. But I do remember the #7 rod bearing looking like that. Why is the problem child usually the #7 hole anyway?
Don

I have a theory on that based on a fairly old (1990) TSB concerning the 302 Ford.
Ford TSB 90-4-14 wrote:
Spark knock or an engine miss may be caused by induction cross fire. This occurs because of misrouted spark plug wires. The firing order of the 5.0L engine is such that the #8 spark plug follows the #7 spark plug. Placing wires #8 and #7 next to each other at the separating bracket may induce cross fire. Eventually, cross fire will cause electrode deterioration of the #8 spark plug.

The 302 Ford firing order is 15426378 and is numbered RB 1234 LB 5678 and the Chevy is 18436572 RB 2468 LB 1357. With both the SBF and SBC the 2 rear cylinders follow each other in the firing order. I know I've been guilty of parallel routing plug wires because it looks neat but since I became aware of this inductive crossfire I stopped it. I sell and install Jasper engines and they started including warnings with their engines about the time this TSB was released. I think the Jasper warning included possible engine damage. Of course none of this applies to the HO version of the 302 with a different firing order or any SBC with the 4/7 cam swap.

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 Post Posted: Tue Nov 29, 2011 9:40 pm 
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I don't see how this could be anything but an oiling issue. The block was used at a higher power/rpm level with the berings looking fine. That's most likely when the main cap fretting happened. I've seen main caps move so bad the mating surface looked like there had been electrical arcing between them, and the registers got beat loose. I'd sand the mating surface flat and run the same berings again. They never came apart looking like that.

I'd be thinking the accumulator some how because that's what's different than when it was ran with the 18* heads.

The crank is new too. Maybe the oil holes in it?

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 Post Posted: Thu Dec 01, 2011 9:14 pm 
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shrinker wrote:
In the picture of the 2 pistons with brown on them what is with the rings on the left piston. Are they dark from heat or what?

I looked at the higher res original and the rings closer. The top ring looks darker on part of the ring due to lighting. The 2nd ring is black on the upper surface and half of the face from the original oxide (or whatever) coating from the manufacturer. The lower half of the face of the 2nd ring is the worn/contact area and is normal bare metal colored. I don't see any signs of heat.

Rick


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