M1 TDT 5W40, run 14hrs, racecar Miata 1.6 turbo

Status
Not open for further replies.
Joined
Jun 2, 2009
Messages
7
Location
southern CA, United States
I run a Miata in a cheap endurance racing series. The engine is a assemblage of used stock (but basically serviceable) components, which we then turbocharged.

Before its most recent race, we put new main bearings in it and added an oil cooler. Then we refilled it with virgin M1 Turbo Diesel Truck 5w40 and ran a 14 hour endurance race. Then we did a UOA.

First, here is the VOA of the M1 TDT 5w40. Sorry for the goofy formatting, I can't seem to get the numbers to line up nicely under the respective column headings:

Cu Fe Cr Al Pb Sn Si Na K B Mo Ni Ag Ti Sb Ca Mg Zn P Ba
0 2 0 1 1 0 5 0 2 86 1 0 2 0 1 2596 556 1444 1252 0

ST OXI NIT SUL W A V100 TBN ISO
0 0 0 0 N N 15.0 12.0 17/14

5μ 10μ 15μ 20μ 25μ 50μ 75μ 100μ
1000 217 101 61 43 22 18 13

--------------------------------------------------------------
Here is the UOA after the 14hr race:

Cu Fe Cr Al Pb Sn Si Na K B Mo Ni Ag Ti Sb Ca Mg Zn P Ba
7 14 0 5 3 1 41 42 1 89 16 2 0 0 0 1469 792 1198 1094 0

ST OXI NIT SUL W A V100
0 15 10 18 T N 11.7

---------------------------------------------------------------

Unfortunately I forgot that the TBN test was extra and don't have a TBN for the UOA.

The UOA report notes "TRACE LEVELS OF WATER DETECTED. SODIUM LEVEL IS ELEVATED. NO GLYCOL DETECTED. SILICON AND
ALUMINUM LEVELS ARE ELEVATED AND MAY INDICATE DIRT ENTRY. INSPECT FOR SOURCE OF DIRT ENTRY INTO THE SYSTEM."

I'm new to UOA. Anything else here jump out to you guys as concerning? OK to run another 14hr race with this oil as-is?
 
No. Yes.

Formatting is a pain. You can use "fixedsys" as a font and ...'s or ___'s to separate things, but it always looks bad.

TBN probably wouldn't have shown much anyway.. IMO.
 
They probably still have your sample if you want a TBN from it, just call them and ask. Putting the info vertically makes it easier to read, look at a few other UOAs for examples. Silicon is worrysome at 41, if I'm reading it right.
 
Good idea. Here's the same data in columnar form so its somewhat easier to understand.

The first column of numbers is the VOA, and the second column is the UOA:

Cu 0 7
Fe 2 14
Cr 0 0
Al 1 5
Pb 1 3
Sn 0 1
Si 5 41
Na 0 42
K 2 1
B 86 89
Mo 1 16
Ni 0 2
Ag 2 0
Ti 0 0
Sb 1 0
Ca 2596 1469
Mg 556 792
Zn 1444 1198
P 1252 1094
Ba 0 0

ST 0 0
OXI 0 15
NIT 0 10
SUL 0 18
W N T
A N N
V100 15 11.7
TBN 12
ISO 17/14
5mu 1000
10mu 217
15mu 101
20mu 61
25mu 43
50mu 22
75mu 18
100mu 13
 
You really beat the h%ll out of that oil - TDT doesn't usually shear that much - M1 0W-40 is usually the one that shears. You put it comfortably in the 30-weight range.
 
This was a just re-assembled engine, right? So we're basically seeing break-in.

Nonetheless, you also beat the [censored] out of the oil. I've never seen M1 TDT shear to a 30 weight without substantial fuel.
 
Pablo--yes sodium at 42.

JoeFromPA--it was newly reassembled, but the only actual new parts were the main bearings. The rings and all else were re-used.

So no break-in per se, as break-in pertains primarily to seating the rings.

We are running this oil pretty hard by streetcar standards as we feed it full load and a 7krpm redline over and over for 14 hours.
 
Quote:
I've never seen M1 TDT shear to a 30 weight without substantial fuel.


I looked a couple of times. I see neither fuel %'age or a flashpoint. How do we know it wasn't fuel
54.gif



..or did I miss something?
 
How did this part of the report change so much? :

Ca 2596 1469
Mg 556 792
Zn 1444 1198
P 1252 1094

Doesn't even look like the same oils. One looks like CI and one looks more like CJ.
 
Originally Posted By: Gary Allan
Quote:
I've never seen M1 TDT shear to a 30 weight without substantial fuel.


I looked a couple of times. I see neither fuel %'age or a flashpoint. How do we know it wasn't fuel
54.gif



..or did I miss something?


You are absolutely right...I skipped over the fact that i DIDN'T see those indicators. And I assumed since it was a straight run at the track that it wasn't fuel diluted.

My bad....this car could be dumping fuel in the oil like crazy with it's tune.
 
There's some dilution as the car runs rich at part throttle / low rev / idle. Full load is relatively lean as boost is low and we're trying to stretch the fuel supply.

Jaymus--I dunno why those elements are lower now. Any theories?

Also I goofed, we replaced the rod bearings, not the mains.
 
Last edited:
My theory is you got back the wrong UOA. I'm really curious to hear other thoughts on this, as well. The difference is too big in each additive that it can't be a 'minor discrepancy'. Unless you had a quart or two of a different oil left in there after your change to M1 TDT 5W-40. But it sounds like this engine was opened up and when put back together, refilled with TDT 5W-40, so surely that isn't the case.
 
that is one beat up oil, which is really surprising, the miata engine is usually a kitten with oil. i am assuming that the turbo is doing much of the damage here, a NA miata will go 10k on 0w40 and have another 5k left in the oil. i certainly would change it before running another race, it might come back as a 20wt.

i doubt RL or anything other than perhaps RLI BioSyn would do any better. at the price points, you are better with TDT and a per race change.
 
It looks like this one particular UOA has spread life wildfire in people's minds on this site that ZDDP gets 'eaten away'. I'm not saying it doesn't, but I've seen this particular post linked to to 'prove' a point and lots of threads brought up asking about how much ZDDP gets used during a UOA. I still think these oils aren't even the same oils. EVERYTHING changes about them. The Calcium goes down, the Magnesium goes UP?!

Has anyone ever figured this out? It wouldn't be the first time a company got a UOA mixed up with another customer's UOA. I just don't see this VOA and UOA being the same oil.
 
Interesting. FWIW the company that did the VOA and UOA was Quinn Company (Caterpillar) in Fresno. Dunno what position in the oil analysis totem pole they sit but there it is.

This was a nearly totally 'pure' fill of a reassembled engine--the only residual oil was in the oil cooler, and that had been draining for days prior. So no real contribution by old oil.

Wait, maybe some assembly lube was in there?? I'll have to check with my teammate.
 
Status
Not open for further replies.
Back
Top