View Full Version : Metal In Oil, How Much Is Too Much?
12-15-2002, 12:03:00 AM
I just got finished last week installing my new engine. I did the normal 30 min cam break in, drained the oil, and replaced the filter. There was some metal in the oil, but nothing big. There was some real small flakes in the filter also. Refilled and let sit until today. Readjusted all of the rocker arms and started back up. Let it run for another 30 mins, no knocks or abnormal noises coming from the engine. Engine ran really smooth, no misses. Oil pressure was steady about 55 psi after warm up. Shut down, drained oil and replaced filter. Small amount of metal in drained oil a lot less than the previous run, could not find much in filter either. On a previous rebuild, I had a lifter collapse and a cam lobe went flat and now I am a bit paranoid about ANY metal that I see. I know that there is going to be some from the new bearings and a lot is bad news but what should be normal? Thanks. RH
12-15-2002, 12:29:00 AM
I have never seen any metal come out before on a new engine or even an old engine. I would be concerned. Im not sure what you can do at this point unless you want to pull it and take it apart again. I think something is rubbing somewhere or is not cleananced correctly. Its up to you either run it and time will tell if everything is ok or you can pull the engine back out and pull it apart. Im not sure which way I would go, thats a hard call. Im thinking I would run it a while and change the oil again and if I found anything I pull it and find out why. If no metal then just run it.
12-15-2002, 12:39:00 AM
Based on my time working on aviation piston engines, if you can actually see metal flakes etc....then something is wrong inside there somewhere.
If this were happening to me ...and the motor ran well and sounded good....then I'd probably keep dropping the oil say every 500 miles for a few changes and see if the visible metal stops appearing. Also, it is possible to take a sample of the oil in for analysis - they can tell what type of material is in the oil so you know where the problem may lay. Usually, analysis of oil is carried out by heavy vehicle maintenance outfits or aircraft maintenance workshops....they could advise you who to send the sample to.
76 Trans Am
70 Camaro SS/RS
12-15-2002, 09:35:00 AM
Did you put a magnet to the shavings to be sure it was metal and not bearing? Chunks of stuff would worry me a little too but an engine is a hostile place and you really don't have any time on the motor. Run it for a few miles and check it out.
12-15-2002, 10:55:00 AM
I have a magnetic drain plug in the pan. On the last run, there was NO metal on the plug just in the drained oil. Thanks. RH
12-15-2002, 06:48:00 PM
I ran the engine again today for about 45 minutes. Drained the oil and there was very little in the drained stuff. Nothing at all on the magnetic drain plug. Engine still runs fine. Backed it out of the driveway just to check the transmission. Put it in low, gave it some gas, and it chirped the tires. Felt good! RH
12-15-2002, 08:04:00 PM
If you see it in the oil but no flakes on the magnetic drain plug it may be metal dust from the distributor gear wearing in. Is it a bronze gear. Did you prelube the engine before starting it. How detailed was the rebuild, complete bore, hone new pistons, etc?
12-15-2002, 08:35:00 PM
Not a bronze gear, but new on distributor. Everything brand new inside. New Comp Cams 265 and lifters, new .030 JE flat top pistons and new rings, new double timing chain and gears, new rod and main bearings (Clevite 77), new Melling oil pump, new hardened pushrods, new roller tip rockers, new Edelbrock performer, and new World Sportsman heads. All of the clearances were checked with plasti gauge. Block was completely redone, decked, bored and honed, hot tanked, new cam bearings and freeze plugs. Crank was turned .010. Rods were resized and the whole rotating assembly was balanced. Assembly lube used and especially the stuff that came with the cam. Before it was started the first time, I primed the oil pump and carburetor. It started witin 1/2 revolution of the engine and ran fine throughout the 1st 30 mins. RH
[This message has been edited by rogerh (edited December 15, 2002).]
12-18-2002, 01:11:00 PM
I ran the engine again for about 45 mins, readjusted the rockers and let run for another 30 mins. Almost nothing to see in the oil and filter. Just a flake or two. Any comments or suggestions? Thanks. RH
12-18-2002, 01:49:00 PM
if the block wasn't completely cleaned, you may be getting residue from the hot tank. If the machine shop has a large tank that holds several blocks you would be surprised the crap that winds up in your block. I run one of those screens that sits on top of the oil filter and a magnetic drain plug in my race 468. When I rebuilt it last year, the screen caught small specks of paint! Only thing I could figure is this trash was hide in the block somewhere, it took 3 oil changes to get it out. Never had any problem with the engine either. Race it every week.
If it runs and sounds okay with good oil pressure and good water temp I'd run it but be easy on it for a while.
12-20-2002, 03:35:00 PM
I ran the engine again today and found more flakes in the oil. Engine is coming back out this afternoon. I think that there is a rod or main bearing problem now for sure. RH
12-20-2002, 10:35:00 PM
Man that sucks. Let us know what you find.
12-21-2002, 11:38:00 AM
Greg, thanks for the sympathy. I'll let you know. It will have to wait until after Christmas. RH
12-23-2002, 12:49:00 PM
I use Blackstone Labs for oil analysis. http://www.blackstone-labs.com They'll send you free drain kits. You'll want to get a drain right after the engine's been run, though- otherwise, it won't be a good sample (particles will settle in the pan). $18 for a test. I check mine occasionally (1x/year) just to see what they say.
They'd be able to tell you what's in the oil.
01-03-2003, 12:56:00 PM
I pulled the oil pan off the engine yesterday and checked each of the main and rod bearings for anything abnormal. I only pulled the caps from the mains since that is where the most wear would show up under normal conditions. When I pulled the rod caps, I pushed the piston down far enough to check the upper rod bearings also. The only bearing that shows any real abnormal stuff is the rear main. I have some copper color showing on the rear edge of the rear main. This is defintely not normal wear and it looks like there may be a problem with maybe a torque converter. This is the only thing that I can think of that would cause this problem. Can anyone give me some ideas on this? Thanks. RH
01-04-2003, 09:42:00 AM
Bad you had to drop the pan, good that you found a problem. Post a question in the engine topic or email Marv. How much space between the torque converter and the flywheel.
01-04-2003, 06:31:00 PM
Did you plastic gauge the crank?I don't think it would be your converter.Also sometimes if the block needs a line hone or bore it will show signs of wear on the edges of the bearings.
01-07-2003, 01:20:00 PM
Thanks for all of the replies. I did plastigauge the bearings initially. I did keep the previous set of bearings from the first run and comparing that rear main from this one shows that the wear is about in the same area. I am going to pull it back completly apart, get new bearings, and re-check everything again. I am not really sure now that the crankshaft may have a problem that I did not catch. Looking closer at the main caps, I noticed that the bearing wear from the front of the engine to the back of the engine increases from no wear on the front to lots on the rear, and this was evident on both sets of bearings. Hopefully, I can make some kind of sense out of this mess. It's too cold to work on this now and I am going to wait till it gets a bit warmer. RH
01-07-2003, 03:36:00 PM
With just the crank in the block does it turn freely? It's by no stretch a test to check main alingment but if it turns with resistance then you know you have a problem.
We used to have the contract for Toyota industrial engines. Part of the spec per rebuild was field testing of oil. we sent it to their lab and had a complete report of more things than I understood,ha. They never got too excited with initial reports of some metal but past 500 hrs they expected almost none. I think it is a good guide and for the money worht it on a fresh engine. Let us know what you find.
01-07-2003, 08:08:00 PM
By the GM book, it says that without any of the rods attached and all of the mains torqued to the proper settings, you should be able to turn the crankshaft with the torque wrench set at 35 ft/lbs and it should not click. This was true in my case. I could just barely spin this with my hand. It took a very little amount of force to turn it freely. Thanks for the replies. RH
03-05-2003, 03:15:00 PM
The weather here has been nice for awhile and pulled the engine apart again. I mic'ed the crank and all of the journals were well within specs. I went down to the machine shop and showed the machinist both sets of previous bearings and the similar wear on both sets. He told me that doing an align bore/hone on the mains should take care of the problem, so I took the block and the crank back over to have the work done. I got the block and crank back yesterday and installed the new bearings and used plasti-gauge again to make sure. ALL of the plasti-gauge readings on the mains were .0015 - .002. I will be putting the rest of the engine back together soon. Hopefully, this will take care of the bearing problems. RH