Bearing Analysis Please

[Flyin Brian]

I blew a head gasket last year and finally finished tearing down the motor.
I got some water in the oil when the gasket blew. Bearings do not look too good. About 1000 miles.
Crank was turned during last refresh and still looks perfect. Line bore was done when installing the steel center mains and ARP studs several refreshes ago but I am beginning to question the main bore alignment. The rod bearings look funny too. I don't know how much of this is due to the water getting in the oil. I had the big ends of the rods measured last time and they were in spec. I had a machine shop check the main bore last time and they said it was ok but I do not know how they checked it. I have since changed machine shops and am going to do all of the assembly work myself this time. My plan is to get everything checked and do all of the necessary machine work as well as replace any parts that are out of spec. This will be the re-build where I finally get everything right. Here are the bearing pictures. What do you think?

 

[Chuck Leeper]

How was the crank polished? All the brgs look to me as tho they were run against a rough journal. The polishing has to be done in the correct rotation, so the "fuzz" doesn't go against rotation direction.
Also, was this crank set up tight?
Did the water have antifreeze in it?
Water displacing the oil film could also be an issue. How long was the engine run, after the h/g failure?

 

[bison]

Its really hard to see the bearings in the pics. The mains dont look too bad other than the score lines from debris. Doesnt look like a lot of embedded debris but cant say for sure in the pics. The rod bearing uppers look like they saw some uncontrolled combustion events. Center of the upper bearing insert is worn

 

[Flyin Brian]

How was the crank polished? All the brgs look to me as tho they were run against a rough journal. The polishing has to be done in the correct rotation, so the "fuzz" doesn't go against rotation direction.
Also, was this crank set up tight?
Did the water have antifreeze in it?
Water displacing the oil film could also be an issue. How long was the engine run, after the h/g failure?

I believe the crank was polished in the right direction but I will have to check. The guy that cut the crank 10/10 polished it. He is the best crank guy in town. Had a pile of Bryant cranks he was working on. He is the one that measured up the crank last time and found that it had almost a thou of taper on some of the journals (GN1 crank I bought new in 2010) from the factory.
The crank was set up "tight" meaning it was within the factory clearances. It was on the wide side of the factory specs, .0018 to .0020 I think. I will have to dig that info up. I know many people set them up looser.
The water was just water and RMI 25. The motor was run some after the head gasket let go but when I drained the oil it did not look that bad. Only the oil that was left in the bottom of the pan had the milkshake look to it. To be honest I drove it home about 8 miles after the head gasket let go as it sounded fine when not under boost and I did not know I had blown a head gasket. I won't do that again now that I know what a blown head gasket sounds like.

 

[Flyin Brian]

Its really hard to see the bearings in the pics. The mains dont look too bad other than the score lines from debris. Doesnt look like a lot of embedded debris but cant say for sure in the pics. The rod bearing uppers look like they saw some uncontrolled combustion events. Center of the upper bearing insert is worn

I will post some better pics today of the mains. It was number 1 cylinder that blew the head gasket this time. This motor saw very little detonation ever according to my logs and knock sensor. The knock detector would beep once when rolling into the throttle under very low boost sometimes. The most knock it ever saw was about 1 degree of retard near 20 psi boost. The motor never saw more than 20 psi boost. It looks like I was pulling in some oil mist through the PCV as the inside of the intake manifold had some oil on it as did the tops of the pistons.

 

[Flyin Brian]

more pics

Looks like a little debris passed through a few of these. Probably tiny pieces of the vaporized head gasket that blew into the lifter valley when it let go.

 

[bison]

I will post some better pics today of the mains. It was number 1 cylinder that blew the head gasket this time. This motor saw very little detonation ever according to my logs and knock sensor. The knock detector would beep once when rolling into the throttle under very low boost sometimes. The most knock it ever saw was about 1 degree of retard near 20 psi boost. The motor never saw more than 20 psi boost. It looks like I was pulling in some oil mist through the PCV as the inside of the intake manifold had some oil on it as did the tops of the pistons.

All cylinders had detonation. #1 was worse than the rest. Gauges showing or not showing doesnt matter. If you're blowing head gaskets then you have to re-assess


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[Flyin Brian]

I am trying to figure out the detonation thing but it is hard to figure out when it does not always show up on the data logs or the knock sensor beeper. I wonder if the valves floating or the oil getting sucked in through the PCV could contribute to the detonation? I am going to go richer and reduce the timing more when I get it back together. I have the right valve springs in it now and will go back to plugging the PCV line like I used to in the past. I will check out my fuel supply situation as well.

 

[No disintegrations]

engine oil can detonate, too much timing or not enough fuel, or poor meth distribution all should be considered.

edit : I see you're on e85? please ignore meth comment.

 

[Flyin Brian]

Step one is to get the short block built back right. I will be taking the block to the machine shop next week to get everything measured. I am already .035 over and will probably have to go .040 and get new pistons and rings. I feel like I should have them do an align hone on the mains just to be sure that they are right. Also need to get the big ends of the rods checked. I also plan on getting the block decks resurfaced. If that block ends up being a boat anchor I have another block that is .030 over now that I can get checked out and use if necessary. If that one turns out to be a boat anchor too I will be block shopping. As I mentioned before this build will be done right. Once everything is mechanically correct I will get it in the car and running and figure out my tuning issues before I floor it again. Is there anything else on the block I should get checked when I take it in? Deck height? Crank to cam centerline?