Metal Particles in Freshly Rebuilt Motor

[Britalia]

105 series 1300 motor, professional rebuild on short block. I installed the head, etc. The block had been in storage for many years, but was professionally cleaned.
Motor was run briefly, and oil drained. I found a lot of small bright shiny particles (non-magnetic), and not big enough that you could feel them with your fingers. I drained that oil, and refilled and ran the motor for about an hour. I just pulled the oil filter and drained the oil from it, and found the same small fine particles.
Any advice/experience appreciated. I was supposed to take this car to the track in two weeks, but I think that would be a great risk. The block was drilled for direct oil to the 2 and 4 mains, so there may have been some aluminum debris created, but these particles don't look like irregular shavings. They are tiny, sparkly, and non magnetic. I think I have to pull the motor and start over. Any suggestions on where to look, or what might be wrong are appreciated. I think my racing season is over... maybe next year.

[gprocket]

Apart from the metal particles, how does the motor run? Does the oil pressure hold once the motor is at temp or does it drop significantly. Is there any unusual valve train noises?

It certainly seems likely that the metal particles are from the drilling. There just isn't much non-metallic besides aluminum and there isn't much aluminum that is in contact with something rotating that would create small particles. I would also think you would be hearing some horrible noises.

Assuming it is from the drilling, the next question would be did they travel through the oil passages to get to the sump or were they already lying there in some corner waiting to scare you.

Were it I, the first thing I would do is remove the cam cover and look for any signs of particles. Then I would pull the motor, remove the oil pan and pull the #2 and #4 main caps and see if there is any sign of scoring. Then, assuming they have threaded plugs on the outside of the block I would pull those and run a small pipe cleaner down the bore and see if there is anything in there. Did you replace the oil filter? If so, were there particles there also?

Probably the smart thing to do is tear it down and go over everything but I was never accused of being too smart.

Good luck!

[Britalia]

Thanks for your reply and suggestions,
The motor seems to run fine. No unusual noises, idles smoothly. Water temperature normal. I did have the oil pump modified with a ball bearing pressure relief, so the oil pressure behaves a bit differently, but there seems to be adequate pressure.
I checked some old bearings and they are magnetic, but I wonder if the thin coated wearing surface of the bearing is not ?? Would worn off (abraded) bearing material be shiny ?
Thanks again for your help. I think I see myself pulling the motor out.
Chuck

[genericwood]

Chuck, if you had then engine "professionally" done, the first thing to do is talk to the engine builder. Depending on much debris is there, I might be tempted to run it. The oil filter will pick up even the really small stuff before it reaches the bearings. Unfortunately, there are so many sources of aluminum in our engines that you might not ever find the source.

Just how much debris is there? And is it less after the oil change, or the same?

Erik

[Britalia]

Thanks Erik,
The amount is hard to quantify, and I think/hope it is concentrated in the filter. The flecks from the oil in the filter cover the bottom of a medium size (15 inch diameter) oil change pan, but it does not feel "gritty". The second oil change seems to have a bit less than the first one, but not enough to indicate a trend.
I think my engine builder may not have been very thorough in cleaning out the block, and I could be looking at debris that was there from the first life of the motor.
My engine builder has not responded to my questions, but when I picked up the short block, he thought it might be time to turn the car into a museum piece. Maybe he had a premonition.
Chuck

[Gordon Raymond]

Sounds like the old dirt-in-the-toolbox excuse from your builder. These particles could come from anywhere, cam bearings, loose timing chain carving the front cover, machining debris in the head oil galleries, block galleries, crank galleries, or, even bearing material. Reworking old oil pumps can create all kinds of small stuff, particularly if the idler stud and gear were not replaced, and have a worn the stud or bottom of the gear. Then the idler will shave microscopic chips from the inside of the pump housing.
Most of these microscopic chips can be seen, but by the time they are large enough to feel, they will eat up the engine in short order.
It IS time to revisit your engine builder, WITH samples of the particles.
Just my opinion.

[gprocket]

Again the prudent thing to do would be to tear it down (or have the builder tear it down). But I would think that if you were seeing the babbet from the bearings coming off you would be either hearing something or I would expect the oil pressure would drop to zero once the motor got up to temperature. As the oil starts to thin and the gap widens in the mains, oil pressure drops and the cams starve for oil. Lots of noise and oil pressure goes way south. This doesn't sound like it is the case.

The other thing to do would be to run sludge remover through the motor. Perhaps (I'm just talking out loud here) you could drain the oil, filtering it through cheeze cloth and reuse it. I'm thinking about filling it, run it a bit, drain and filter and repeat. If the particles go away and everything else seems normal then... off to the races.

Good luck

[junglejustice]

I'll probably get shot (or at least shot at a few times) for saying this, but here goes;

Any engine-builder who wants to be a bit honest (and who has at least seen dozens - if not hundreds of rebuilds), will readily admit - if he wanted to be honest - that it is quite "normal" to see a bit of fine crap in the filter at the time of the 1st oil-change!

It is VERY hard to get it ALL out of every single little oil-passage in a block (especially if you did something like a line-bore, if you decked the block or if the motor spun a bearing before rebuild. Like Eric also said - the filter catches it (even the fine stuff), before it reaches the bearings.

It is quite frightening when you see it for the first time, but cut open the new filter from a fresh rebuild sometime and see what is in there!

[180OUT]

Personally, I don't think you should drive any motor, to say nothing of racing it, unless you are 100% confident that it is good. You have too much invested to just drive it around and see if it's going to break---which is what you'll be doing if you drive it now. Further, generally speaking, shops will not stand behind a blown up motor that's been raced.

So, if it were mine, before I did anything else I'd have a sample of the oil analyzed by a lab. That can tell you a lot (like whether or not you have bearing material in the oil---bad) without doing anything else. The next step is to pull the motor and check the bearings. That's not all that hard to do because you don't have to take the motor completely apart to do it.

[ncipps]

when you rebuild a motor you will always have metal particles. Your installing new parts into your motor and they have to seat and in turn they produce metal particles. After about 500 miles you drain the oil and filter and retorque the head and adjust the valve clearance. After the break in period of which you shouldn't push the car too hard you should be fine.

[La Voce]

Good advice from 180OUT, and I second it. I recommend Blackstone labs: Blackstone Laboratories. I used them when I owned an airplane and they saved my backside once. They know engines and oil analysis and it's well worth the modest cost of a sample.