odd 4age oil pressure issues. up and down in pressure.

[oldcorollas]

is weird.
is probably not oil temp, would have to get really hot to drop pressure that much

also probably not actual bearing clearances..
is there anything else in the system that could give intermittent oil loss, apart from relief valve?
if there is shit floating around in the engine,it could temporarily stop relief from closing.. then later get blown out and seat again? perhaps?

could also be that shit is killing each pump in turn? but pressure coming good again would be odd if pump was shagged...

dunno man, see if there is shit in oil or sump.. dunno if you can try and blow out the galleries with air or?

[allencr]

MAHLE Clevite - Bearing Analysis - BETA v3
Here's a link to Clevite's bearing failure analysis pictures so you can get a handle on what actual lack of lube failure (12 & 16) looks like compared to what your engine is doing to'em.

[wiso]

something tells me I might have something wrong with that crankshaft. I span a main bearing the other day. checked it 400km ago and it was ok, didn't show any worse wear than the other 4. has a few lines in the bearings you would probably put down to foreign particles in the oil.

pulled it out now to have a look see number 1,2,4,5 are about the same, no worse but number 3 has the condition that guide above refers to as hot shot. the bearing face has been ripped off and the bearing is cracking everywhere.


So hypothetically could a slighty bent crank or block be giving me the odd oil pressure issues I have been seeing?

I guess I will have to pull the crank, take it in again and get it checked out.

[wiso]

the 2 halves on the left are from number 5. and the 4 look about the same, these are the worst 2.

the 2 halves on the right is the number 3 middle bearing

[oldcorollas]

geez that doesn't look happy... never good to see
clearances before being assembled?
if crank is straight and clearances ok....

shit in oiling system or blocked gallery to that bearing?

[wiso]

gallery, do you mean the oil hole in the crank? might be blocked, or is there one in the block above the crank? heaps of oil poured out of the hole in the crank when I span it to get the bearing out.

Clearences were about minimum clearence on all. I can't remember exact, I did the assembly work quite awhile ago.

like I said considering only the middle bearing is shot the rest are slightly marked it leads to be either a bent crank or warped block. according to the internets.

[dnegative]

For the 1000km on them, they are absolutely fucked. Something has gone through those.
Ive pulled bearings out of motors with a million km on them that have looked better than the ones on the left.

If the block was fine before and so was the crank then I doubt they became bent or warped over night.
Either its significant contamination, poor assembly or incorrect journal finish.

[oldcorollas]

what are all the little bits embedded in the ones on the left?

if you dunno what they are, you can send me a couple of bits and I can analyse their composition

[wiso]

the block and crank are from differant motors. i honestly don't know if they were ok before never drove the engines.

i assumed the bits in the bearing are rolled up bits of the surface from the scratches.

[TERRA Operative]

I'd be checking the journal surfaces on the crank, and check straightness for good measure, then flushing out the oil galleries to get rid of any swarf etc.
Also, have you cleaned out the oil passages in the crank? When I rebuilt my silvertop, I had the ball bearings pulled out so I could clean out the passages then tapped the holes and threadlocked grub screws in. There was a bit of coked up oil in there causing a reduction in oil flow.

Also, just for interest, pull the cams and check the journals and lobes there too.

[dnegative]

Cams are good, they ran in my motor without issue but yeah the journels in the head don't like no oil conditions.

If your getting the crank cut, get the block hot tanked, decked, honed and get the tunnel bore checked.
Better to eat noodles for a week than kill another crank and set of shells.

[allencr]

Really way past time 4 another set of hands& eyes to look at it, as there's something/s that you aren't seeing & aren't knowledgeable about. Repeating isn't going to get any better.

[andrew_mx83]

Did you mix up the main caps, put one on facing the wrong way, or use one from another block?

Also ALL the galleries need to be cleaned out before that fires again. Tear the whole lot down, clean the main oil gallery in block and head properly, any oil lines, cams, sump, oil pump, etc or you will be doing this yet again


Edit: when you turn the motor over by hand after reassembly how does it feel? Any tight spots? It should glide easily before pistons go in and have a bit more resistance but still turn smoothly once they are in

[allencr]

[color size bold bump
howsit go'n?[/
Run your fingernail across rod & main journal surfaces for roughness. Smooth as or almost smooth as glass is preferable.

[wiso]

haven't touched her since pulling the bearing out. really heartbroken.

the $300 ish people want for crank grinding and checking for straight and then $150 for new bearings again i honestly won't have for a long time now. too many other big bills lately. so tearing down to redo cylinders is not what i wanted to do.

the journals aren't that smooth now. they were on the first bearing change out. but now that middle one has some scrathes your nail drops into.