Metal in engine oil? We are stumped!

Technical and Repair Discussions

Still Learning to Type
Still Learning to Type
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PostPosted: Wed Sep 09, 2015 7:24 am
Thanks Sal!

I suspected aluminum because it was not attracted to a magnet. It was otherwise very shiny and white for a metal. The oil pan plug has a magnet on it and it had picked up smaller bits of metal, and they seemed relatively minor. I did not see the much of the bronze haze in the oil you get when big bearings go out. But things were hectic on that day. The CSR was crewing a dozen cars and I was a sideshow. They did the best they could, but it was rushed and a bit dismissive.

I wish I had gotten the filter to cut it open, but it is with the CSR now.

I am probably going to get another sitrep out to Enterprise and see what they suggest. They have been very friendly and attentive to my concerns. I want to lay out some options if the engine only makes it 3 or 4 more races. I am making sure I have video of all of the sessions to be sure to show no over-revs or anything like that!

Forum Hermit
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PostPosted: Wed Sep 09, 2015 9:12 am
I too had an newer engine that drops oil pressure to zero for a heartbeat but only after hard braking followed by a hard right hand turn, then instantly returns to normal. It is more likely to do this with the oil level set at mid range rather the filled to the top of the dip stick range.

I changed the gauge to another brand and it still does it. Both gauges were stepper motor type and are known to react quickly.

It's been a good engine for two seasons al still is.

I have never noticed any aluminum in the oil. Could this be trapped oil from an early engine failure. There are very few places a SRF motor that can shed aluminum for very long with a major failure

Thoughts:
a) I often wonder how my SRF pulls out of a corner so well when the oil pressure was just at zero as don't the lifters need pressure to work.

2) Maybe it is more normal then we all think but unless you have a certain type of gauge/sensor you simply never see it.

Needs a Life!!!
Needs a Life!!!
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PostPosted: Wed Sep 09, 2015 9:24 am
LT - a few years ago I had an oil gauge that gave erratic readings - both the CSR and myself changed the gauge and sending unit - still was erratic - finally I found it wasn't getting a good ground from the threads to the block - changed that connection and no more problem. Maybe when you are in a corner the ground is momentarily lost due to lateral g force?

Still Learning to Type
Still Learning to Type
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PostPosted: Wed Sep 09, 2015 4:44 pm
Thanks guys! Much food for thought here...

Clay, the gauge could certainly be an issue. We just replaced that and it will be ready for the next race. It was the first thing the CSR suspected. He also replaced my spark plug wires. I will breath easier knowing the gauge is new and working right!

The confounding thing is how many things came together in a single incident.
We had:
-Small engine stutter at apex
-oil pressure to zero for a second or so
-erratic pressure readings at high g-forces
-unexplained metal shavings in the oil.
All Taken together is what is scary!

The engine was supposed to be a full remanufactured engine, so it should not have any gunk from any previous failures. When we got it, it was shiny, new and ran nice. Damn, was it powerful too!! During the first race weekend , I was checking the oil constantly after each run. The oil was clear as a bell. It did not even burn any oil that we could see on the levels going down. It seems that wherever the aluminum came from, it came during that second race weekend.

If these things came with a proper warranty, I would just run it and let it blow. But, l want to be thorough, and not waste a motor (or a race weekend!)

Thanks for the thoughts guy! Keep them coming. I am making notes and these things will help me if I need to trouble-shoot on the fly at the next race!

Ready to Write a Book
Ready to Write a Book
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Joined: Thu Dec 01, 2011 10:23 pm
Location: Swaziland, Rhodesia
Chassis:
11&245
PostPosted: Wed Sep 09, 2015 10:25 pm
Depending on how your oil lines are plumbed, and if you did have a blown-up engine in the car before you got this rebuild, you might have had trash stuck in the oil cooler which may now be making its way into the sump. Did you take out a tired engine or a blown-up one? If the latter, you may need to sonic clean the cooler (or replace it as they're not terribly expensive). Just a thought. Good luck.

Still Learning to Type
Still Learning to Type
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PostPosted: Thu Sep 10, 2015 7:51 am
Thanks Dave. Another great suggestion!

No, my old motor had a nice, gentle seize from oil starvation. The only thing in the oil was some bronze. It seized at low RPM when I was trying to get off of the track after one of those small oil lines on the back of the car popped.

BTW, thanks for always helping me at the track!!!
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Needs a Life!!!
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Location: Greenwich, Connecticut
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860
PostPosted: Thu Sep 10, 2015 9:21 am
LTJohn wrote:Thanks Dave. Another great suggestion!

No, my old motor had a nice, gentle seize from oil starvation. The only thing in the oil was some bronze. It seized at low RPM when I was trying to get off of the track after one of those small oil lines on the back of the car popped.

BTW, thanks for always helping me at the track!!!


Well, if you saw bronze in the drain oil from the previous engine, some of the shiny bearing "babbitt" layer material resulting from that engine's oil pressure failure may have gotten trapped in the oil cooler, as Dave suggested, and then popped loose now.

Let the flushing begin!

Also, your CSR may on the right track with changing the plug wires and securing them away from metal surfaces. Sometimes the plug wires, especially the Motorcraft pieces, can rub on metal surfaces around the head and inductance ground momentarily under hard cornering. It feels like a flutter or fuel starvation. It happened to me with my first Spec Racer about 15 years ago. Of course, this would be coincidental to the oil pressure drop.

Still Learning to Type
Still Learning to Type
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PostPosted: Thu Sep 10, 2015 11:34 am
Thanks Bob! I will contact the CSR with the whole list today.

It looks like the plan we have:
1) get the oil cooler off, inspected and flushed
2) cut open the oil filter
3) flush clean oil through the whole motor & see what else comes out

I think these are great bits of advice!! Thank you to all of my fellow SRF brothers!

Forum Hermit
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PostPosted: Sat Sep 12, 2015 9:44 am
Small engine stutter at apex
oil pressure to zero for a second or two

Sounds like an electrical issue.
Last edited by Robert Mumm on Mon Sep 14, 2015 9:29 am, edited 1 time in total.

Ready to Write a Book
Ready to Write a Book
Posts: 58
Joined: Thu Dec 01, 2011 10:23 pm
Location: Swaziland, Rhodesia
Chassis:
11&245
PostPosted: Sun Sep 13, 2015 10:38 pm
"Small engine stutter at apex
oil pressure to zero for a second or two

Sound like an electrical issue".

I second this. Check and make sure you don't have the B+ wire on the alternator worn though and grounding against anything (usually the edge of the heat shield).
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