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So I've got a 2002 outback ej25 that got it's oiling system clogged one way or another. I contend that it was due to left over blasting beads in the heads from the machine shop. What I need to know, but can't find with searching, is what size the oil holes in the crank are. I'd like to run a test on the oil I saved from the blown engine and see how much vacuum pressure is required to suck the oil thru a hole of the same size as the crank oil hole. I checked the repair manual and have looked all over the internets for the answer but can't even come up with the size of an over-sized hole. Any one have any ideas?

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Assuming having a machine shop work on the heads means you recently did a headgasket to it, the bearing damage is often due to overheating if someone let it run out of coolant. Having rod bearings go shortly after doing a headgasket on an overheated engine is unfortunately a common issue.

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Car never overheated and the oil was drained after the heads were put back on so not likely that coolant was in the oil either.

 

Texan, sorry I wasn't as forthcoming as I should have been with my age. Kinda odd that you check that though. I'm guessing you don't have the answer?

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Car never overheated and the oil was drained after the heads were put back on so not likely that coolant was in the oil either.

 

Texan, sorry I wasn't as forthcoming as I should have been with my age. Kinda odd that you check that though. I'm guessing you don't have the answer?

 

 

it's a joke. (you see, I didn't list an age at all)

 

Someone here probably has a crank sitting around. Should be easy enough to check, even if roughly with a drill bit.

 

maybe you could use some compressed air - from a coupla different 'directions' to move the obstruction through, or 'reverse' of normal oil flow. - though, if you KNOW where it is now, having it shift to an unknown spot might be bad. You sure a bearing hasn't spun a little and is blocking some flow somewhere? Are the beads glass or ceramic?

 

A hole may not create the same drag as a 'passage' so, might not be a helpful data point.

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So I've got a 2002 outback ej25 that got it's oiling system clogged one way or another. I contend that it was due to left over blasting beads in the heads from the machine shop.

 

Glass bead blasting is not an effective cleaning method for cylinder heads unless fully dissasembled to the casting and then properly washed... As you surmise it's because the glass beads get into EVERYTHING. It's too hard to clean them out of all passages and crevices. No machinist worth his salt would glass bead a cylinder head in most cases.

 

What I need to know, but can't find with searching, is what size the oil holes in the crank are. I'd like to run a test on the oil I saved from the blown engine and see how much vacuum pressure is required to suck the oil thru a hole of the same size as the crank oil hole. I checked the repair manual and have looked all over the internets for the answer but can't even come up with the size of an over-sized hole. Any one have any ideas?

 

Your test will be meaningless - a hole is not the same as a drilled passage and never will be. There are too many twists and turns and a passage will have friction just due to it's length that will cause pressure drop.

 

And what would vacuum show? Engine oil is under pressure from the oil pump. It's not drawn through the engine with a vacuum.

 

Also - oil flows from the main galleries drilled in the block to the heads and then back to the sump. Oil in the galleries that feeds the crank would first pass through the oil pump and then the filter on it's way there. The filter would trap glass bead and glass particulate before it ever got to the crank. There is no scenario I can think of where glass beads from the cylinder heads would end up in a rod or main bearing. The lubrication system just doesn't work that way.

 

GD

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I'm not absolutely sure what type of blasting media it was but there are full, clear beads in the oil filter shell about 1mm in diameter. There are also remnants of the blasting media all throughout the engine and clearly in the oil pan and draining back onto the metal plate of the oil pan from above, presumably crushed from the oil pump. See the two images below.

DSC_1358.jpg

 

DSC_1339.jpg

 

I know the beads didn't make their way into the bearings since they weren't scoured, but what I do know is that the oil channels were blocked such that the whole short block toasted itself so bad that the block is unusable.

So, what I was trying to do with a vacuum tester is get an idea how much pressure (negative in this case) would it take to draw the crushed blasting media and oil mixture thru a hole the same size as the oil delivery passages. I know the bypass valve pressure of the oil filter and I know the filter had crushed media in it, so if the filter was clogged and the bypass opened then the slurry of crushed media and oil made it's way into the oiling system. On a cold start (10*F) I know the viscosity was quite high and that's when the oil light came on and then the engine went kaboom!

 

So yeah, the vacuum test isn't perfect, but in small claims the judge may want some pressure data. I'd rather be more prepared than not.

 

Glass bead blasting is not an effective cleaning method for cylinder heads unless fully dissasembled to the casting and then properly washed... As you surmise it's because the glass beads get into EVERYTHING. It's too hard to clean them out of all passages and crevices. No machinist worth his salt would glass bead a cylinder head in most cases.

 

 

 

Your test will be meaningless - a hole is not the same as a drilled passage and never will be. There are too many twists and turns and a passage will have friction just due to it's length that will cause pressure drop.

 

And what would vacuum show? Engine oil is under pressure from the oil pump. It's not drawn through the engine with a vacuum.

 

Also - oil flows from the main galleries drilled in the block to the heads and then back to the sump. Oil in the galleries that feeds the crank would first pass through the oil pump and then the filter on it's way there. The filter would trap glass bead and glass particulate before it ever got to the crank. There is no scenario I can think of where glass beads from the cylinder heads would end up in a rod or main bearing. The lubrication system just doesn't work that way.

 

GD

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What/why are you trying to figure this out?

 

Bottom line ,if you have substantial amounts of blasting media in your engine( if you can see it, you do) , its toast.

 

No its not normal and no its not OK for the shop who did the machine work to have left it in there.

 

Yes it could easily clog the oiling system. If the filter clogged, the filter bypass would open and unfiltered oil would go through the engine.

 

Complain to the shop.

 

This brings up another point , even though its the shops responsibility legally and ethically to do the job according to certain standards , its your responsibility to make sure( if you are the engine builder) that all the parts are clean( and sized right for that matter), before putting the engine together( the buck stops with you).

 

This does not let the shop off( financially) in any way though, unless they gave you the heads unassembled and told they need to be cleaned before assembly( which would be very unusual).

 

If you want proof for court, take the engine to another or a few other machine shops and have them write on their letter heads/ receipts what they see and what likely caused it. This , along with receipts from the shop who did the work and pictures will be good proof for court. Contact the shop with your complaint by email if you can, so you have a record of what was said back and forth. Don't mention law suit.

Edited by Robert Harik
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Take apart the oil pump and bypass. If the oil light came on, it was because there wasn't pressure in the system. If your oil passages were clogged, there would be great pressure, just no flow.

 

If the pickup screen in the pan was clogged with blast media, the bypass valve in the pump was stuck open from chunks of media, or the pump rotors or housing were trashed, then you wouldn't have pressure.

 

With that much glass in the filter, you should be able to take some pretty pictures of the inside of the oil pump.

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I see no reason the filter clogged with glass media, along with pics and any paperwork from another shop wouldn't be good enough for a Judge. perhaps with a print-out fro wikipedia or ehow, etc. explaining the bypass valve function.

 

The other problem with using vacuum is, it maxes out at a little over 14 psi. that wouldn't open an OEM filter's bypass valve(25 psi IIRC ?).

 

sending an oil sample to Blackstone labs for a report would also look good in court.

 

 

You might get some relief in SCC, or from the shop by the threat of a suit, but , be prepared for disappointment.

 

good luck

Edited by 1 Lucky Texan
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Thats a huge amount of glass beads in the pan. That could easily have clogged the filter. Only the poster knows where and how far the beads got. It will be obvious. It doesnt really matter, leaving that many beads in the engine will destroy it in short order, whatever the method. This isnt a "maybe",

'well it could" ... its a major screw up by whoever did the head. The OP has not given very much info though .

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