Engine Bearings Gone

[The Devils Own Chariot]

I have a build with around 3000 miles on it. Engine has no signs of a problem when its running and driving.
I changed the oil last night and cut the filter open. Gold bearing material the size of small rice.
I noticed oil pressure was falling slightly when you give it gas. Lets talk about reasons this could have happened.

Is the dropping pressure directly related to bad bearings?
Can the oil pickup possibly have fallen off then causing improper oil pressure?
Did the builder just F up and how?

 

[JSM]

Re: Engine Bearings Gone

Few possible reasons I see.

Oil starvation: missing pickup, low oil, slosh issues, etc. (had this happen to me twice)
Detonation: Detonation hammers the bearing out. Bent cranks can do similar.
Clearance: Bad clearances on the bearings to start with.

I would put the above in order also in terms of what happens most often.

 

[canadian]

Re: Engine Bearings Gone

Could be any one of those things. Send the oil to Blackstone Labs and they'll tell you exactly what is going on with your engine. You won't know much more unless you take the pan off to inspect what's going on in the engine.

 

[tylex]

Re: Engine Bearings Gone

Not to forget a wrong air fuel ratio!!!Happened to me.To much fuel will wash out the bearings!!!!!

 

[JSM]

Re: Engine Bearings Gone

Not to forget a wrong air fuel ratio!!!Happened to me.To much fuel will wash out the bearings!!!!!

Too much fuel can wash past the rings and dilute the oil yes. You would have to be extremely rich for a long time and not change oil though.

 

[The Devils Own Chariot]

Re: Engine Bearings Gone

Yeah engine is coming out. I hope this weekend. The AFR just driving around was good. AFR at WOT was way rich. It could be a combination of all those things I guess. WOW Jeff two times!! Same engine?
Thanks for the info guys.

 

[JSM]

Re: Engine Bearings Gone

Installed an accumsump after the 2nd time, problem has went away.

I doubt you washed rings down.

 

[TYTILIDIE]

Re: Engine Bearings Gone

Dude that sucks. Beware of your machine shop. I always take my crank and have another shop mic it to make sure it is right. I had a shop once say my crank was done and it only lasted 100 miles. It took it back out and they re-did it, i took it to another guy and clearances were all over the place. Some shops are crap. Hopefully this is not your case. If you lost pressure on the incline, I am thinking maybe a pick up tube fell off?

 

[WyoSyclone]

Re: Engine Bearings Gone

Wow, pieces that size make me think they're off the edge of the bearing... possible thrust failure?? When you give it gas the converter pulls the crank and without the thrust surface possibly blocks the bearing/passages. If you don't run it any more you may luck out and not see a lot of damage.
Sorry to see this happen.. I know how hard you've worked on your Sy. Good luck with the fix.

 

[DaveP]

Re: Engine Bearings Gone

In another thread you recently mentioned "rings didn't seat until we had 20 WOT dyno pulls". I'm thinking there was detonation during those pulls on the brand new engine. While WOT on a brand new engine won't hurt it if it's assembled correctly with the correct clearances, detonation will.

I had the same set of circumstances. 30psi overboost, with SEVERE detonation. 5,000 light miles later, 8psi hot oil pressure, and main bearings and crank were junk. I feel the deto causes the crank to bend and get banged into the bearings causing brief metal to metal contact. The bearings get damaged. Over time the bearing continues to deteriorate, eventually manifesting itself as low oil pressure, and a deep knock on start up or at idle.

Fuel-diluted oil doesn't help matters either. Especially diluted 10/30. It's so thin in the first place, it doesn't take much fuel to get it too thin to prevent metal to metal contact.

You worked hard to get it running again. Sorry to hear of your setback. Hope your re-fresh of the crank and bearings goes smoothly, and you get it going again with minimum expense and effort.

 

[BMFB]

Re: Engine Bearings Gone

In another thread you recently mentioned "rings didn't seat until we had 20 WOT dyno pulls". I'm thinking there was detonation during those pulls on the brand new engine. While WOT on a brand new engine won't hurt it if it's assembled correctly with the correct clearances, detonation will.QUOTE]

Thats true, also, I have to ask about that 20 pulls. Perhaps someone will step in and correct me but I would be looking at who built the motor. When I had my engine built the builder assured me that he had it to where the rings would seat instantly, and they did. I would be currious if anything else like that happened with the rest of the build.

 

[DaveP]

Re: Engine Bearings Gone

I just remembered something. Oil in the chambers (ie, "rings not seated") will promote detonation as the primary cause.

I too wondered about the "rings didn't seal" comment. I've built and assembled hundreds of engines. I've only had one that didn't stop using oil almost right away. What kind of rings did you use? If you used a chrome top compression ring, that could be the culprit. Chrome rings are very hard, and take some time to seal. Moly-filled rings are well suited for use in performance-street engines, and seal almost as soon as the engine is fired. Respected shops and builders have been using moly-filled top rings, and a cast second ring for decades on street-performance engines with good results.

I feel the ring-seating issue is secondary to why the bearings failed, but it could have contributed to detonation if there was chamber-oiling during the dyno pulls.

 

[The Devils Own Chariot]

Re: Engine Bearings Gone

You could see blue smoke out the exhaust all the time. The 20 WOT pulls on the dyno the burning oil smell finally went away. I later checked the compression. The lowest was 140 and the highest was 155. I think it was #1 that was low.
They did use Molly rings.
Im really devastated about this. I have 1000 of hours into this thing. I have a baby due in 7 days and Im sure the money is just not going to be there like it was. The funny thing is the truck runs strong and it made 475 at the motor on 22 psi with only 12 or 13 degrees of timing pump gas and alky (later found the alky feed to the pump had a massive leak on the dyno) You would never know it had engine damage.
Enough of the pitty party. The motor should be out on Monday. I talked with the engine shop. They are going to take a look at it. Dirt oval track racing is big around here and hey build a lot of serious big blocks for that. The one guy that works there pulls at turbo tractor competitions. The other guy has a low 9 second Camino. They seem to know their stuff. Im hoping they stand behind their work. If they dont Im sending my long block with everything on it to Nolan so he can get it straitened out. We also talked about an E85 tune that would be 95% turn key once I get the motor back in the truck.
If anyone is looking for an Alky Control setup and 60# injectors they should be going up for sale.
Thanks for everyone's comments.

 

[turbodig]

Re: Engine Bearings Gone

I have a build with around 3000 miles on it. Engine has no signs of a problem when its running and driving.
I changed the oil last night and cut the filter open. Gold bearing material the size of small rice.
I noticed oil pressure was falling slightly when you give it gas.

The last line is somewhat telling.

Worn bearings tend to show higher oil pressure which falls and knocks when warm.

Normal pressure *increases* with RPM.

Yours decreases with throttle.

What may be happening, is that the pickup fell off or cracked, and that oil sloshes away from where it can be sucked in on acceleration. Thus, the loss of pressure on accel.

Could also be the cracked oil pump housing thing... there was a rash of these a while back.

As an aside... Any chance you had a bronze dissy gear?

 

[ItsMyTy]

Re: Engine Bearings Gone

I noticed oil pressure was falling slightly when you give it gas.

Main bearings that are bad have very large clearances. When the engine is under load, the crank moves away from the top half of the main bearings, increasing the hole for pressurized oil to gush out between the bearing and the crankshaft.

IMO what you are seeing now with the oil pressure dropping under load is a result of the bearing failure, not the cause of failure. Only way to know the cause would be teardown and inspect.

 

[The Devils Own Chariot]

Re: Engine Bearings Gone

As an aside... Any chance you had a bronze dissy gear?

I do not have a bronze distributor.

 

[Don W.]

Re: Engine Bearings Gone

In my experience rings seat fairly quickly. Although I've had bearing issues in the past due to knock I've yet to see ANY oil consumption problems. My own humble opinion is that rings seat almost immediately. IF (big if) they are installed properly with correct end gaps AND those gaps are installed in the correct position. Bearings can go for a lot of different reasons. But if you're getting metal you're gonna have to take it apart and see what's going on.

 

[The Devils Own Chariot]

Re: Engine Bearings Gone

Here is a pic of the filter. NAPA Gold,I didnt know that meant the filter came with gold in it.

 

[canadian]

Re: Engine Bearings Gone

time to pull the motor... suxxorz

 

[The Devils Own Chariot]

Re: Engine Bearings Gone

I was doing some thinking. Crank Bearings are not brass/gold. They are silver. Then I thought about rod bearings. The ones I have seen are rarley brass or gold. The only thing I can think of that is gold or brass is the valve guides......... I think the top side of the eagle H-beam rod has gold/brass also. That seems like an unlikely place for metal to wear Its not really rotating 360 degrees.
Someone chime in.