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Dropped the pan and did some diving last night.

The rod bearings in the front of the motor were smeared a little - nothing too bad, but I had new ones on the shelf so I just went ahead and put them in. A couple rod bearings in the back of the motor were flattened pretty good - which I thought was unusual. It's still plenty fat, so I'm not beating the bearings up, and if it's due to low oil pressure, why aren't the bearings in the front of the motor that bad - they are the last ones to get the oil

Starting to get a bad feeling about this. I'll pull the mains tonight and see if there's a clue in there.

Why can't I just burn holes in pistons like Mike

Why can't I just burn holes in pistons like Mike

OUCH!! ^^^^ But funny still the same.

What did the plugs look like in those cylinders??

Sorry - that wasn't meant to be a jab at Mike - just that once in a while I'd like to have a 'common' problem with this thing.


That cad on the plugs is still shiny all the way around - only the cad on the electrode is burned off - it's fat. There's no sign of detonation. It's running clean, so I don't think it's so fat that I'm putting out cylinders and hydraulicing. (I've done that in the Veney motor in the pulling truck and it does nasty things...) This motors got over .125 piston to head clearance, so I don't believe that I'm running into an interferance issue.

Perry,

That is kind of a strange one. Keep us in the loop on what you discover.

Rapid

Great report, keep us posted.

EDB

The engine's coming out so that I can tear it down and look at it closer. (Got it down to an oil line and motor mount bolts last night...)

Here's what I discovered so far:

I pulled #4 main cap - The first outer bolt was good and tight, the other 3 were just snug. The lower half of the bearing is flattened pretty good, and, for some reason the crank has been rubbing on the back side of the cap.

I grabbed a light and looked up in there - the upper bearing is shoved clear over toward the front of the motor - the aluminum around where the bearing tang is supposed to be is pushed away.

Grabbed a scew driver and pried at the crank around the thrust bearing. It moves back and forth just a little bit - end play is about right. So why the bearing is shoved over ??

I looked around a bit more and I can see the lower half of the rear main bearing sticking out from the edge of the cap - although from what I can see it looks like the top half is still in place. The front bearings and thrust bearing look to be where they belong.

I'd seen enough - stuck the pan back on it with a couple nuts and started the removal process....

My current hypothesis about the flattened bearings is that with the top bearing shoved over, the oil hole isn't lined up any more, which restricted the oil to those bearings. Plus the bearing groove that normally lines up with the oil holes that go to the rod journals wouldn't be lined up with those holes, putting a double whammy on rod oiling. My current thought is that I don't have an oiling problem, I've got a bearing alignment problem.

Perry
Chaotic Headache Racing

Sounds like the #4 main studs are starting to pull out. Was the block welded in this area?

How much torque on the mains Perry? Check em and see when you take em loose. You know, kinda reverse detective work.

The good news.....you caught it before it took itself apart.

How much torque on the mains Perry? Check em and see when you take em loose. You know, kinda reverse detective work.

Yeah - that's what I'll do. I that I'd just changed 8 rod bearings - which are torqued to 100, and when I went to loosen the first main stud, it felt about the same, but when I went to do the other 3 they were nowhere near as tight.

The good news.....you caught it before it took itself apart

Tell me about it! Even it the block's broke, it's a bunch cheaper than replacing all the other parts that get taken out. Plus everything only has 8 runs on it - give me a block and I've got a nearly new motor!