Rebuilt 280zx engine oil analysis report back...

[Lee280zx]

I received the Oil Report for my 1982 280zx. This is the first oil analysis I've ever had done.

There were a total of 163K miles on the engine at the time the sample was taken, but I had the engine rebuilt at 160K miles by a reputable Z shop.

At the time the sample was taken I had 3,290 miles on my rebuilt engine, 1,790 miles on the oil that was analyzed (Valvoline 20w-50 at the suggestion of the shop that rebuilt the engine).

I don't really know what to make of the numbers. In the comments Blackstone said that the engine rebuild is definitely okay ("without reservation," they said). They also noted that the insolubles were low at 0.3%, showing good oil filtration and complete combustion, and there was no moisture or coolant present in the oil.

Here are the numbers:

Mi/Hr on oil: 1,790
Mi/Hr on unit: 3,290
Sample Date: 05/20/03

Aluminum: 2
Chromium: 1
Iron: 8
Copper: 3
Lead: 10
Tin: 6
Molybdenum: 1
Nickel: 0
Manganese: 0
Silver: 0
Titanium: 0
Potassium: 2
Boron: 2
Silicon: 3
Sodium: 10
Calcium: 1885
Magnesium: 7
Phosphorus: 769
Zinc: 965
Barium: 1

All of these numbers are lower than (or equal to) the "Universal Averages" listed, with the exception of the Calcium, Phosphorus, Zinc and Barium, which are slightly higher.

Blackstone said "These wear levels will probably improve as the engine breaks in--we think you'll be able to go longer [drain intervals] once the engine is past the wear-in period."

What do I make of all of this? Do you agree that this indicates a good rebuild? Why?

 

[Pablo]

I agree with the lab. No excess metals, dirt ect..clean engine. Good rebuild. Fe at 8 and Pb at 10ppm may seem high but for 3.2K run on the same oil on a rebuilt motor, not too shabby.

Mostly now watch for trends.

What about the oil? TBN and viscosity?

 

[Dominic]

It looks very solid. Im not sure I would run a 20W-50, I might run a 10W-40, but thats a solid report nonetheless.

What 20W-50 valvoline was it? Full Synthetic?

 

[Lee280zx]

Thanks for the responses...

Pablo--actually the oil tested had only been in for 1,790 miles (and 4 1/2 months--this car isn't a daily driver). After the rebuild I had changed the oil at 60 miles, 440 miles and 1,000 miles. This oil went in when the rebuilt engine had 1,000 miles on it. Does that change your opinion?

I didn't order the TBN because I didn't intend to keep using the same oil. Under SUS viscosity the report reads 83.9.


Dominic--It was just the basic dino Valvoline 20w-50. The shop recommends using it in all the early (pre-'84) Z engines. I stuck with it for the break-in period because some told me that it protects the bearings early on, and I was looking for some wear before switching to synthetic.

The car now has Mobil 1 10w30. After that I've got 0w30 Series 2000 Amsoil I'm putting in. I had the Mobil 1 lying around in my garage, so I thought I'd use it as a sort of "rinse/flush" before putting the good stuff in.

 

[Pablo]

Sorry my bad. Misread it....doesn't change my opinion too much, it's not like you have a lot of wear chunks.

Good early break in change philosophy!!

 

[Schmoe]

Uhhhh......maybe I'm lost here but why is moly so LOW???? I guess it's true to what we've been reading that Valvoline is not using moly anymore.

 

[Al]

Congratulations-looks like you goot a good rebuild-so far.

 

[MNgopher]

Looks like a nice, clean rebuild. Nothing to worry about here!

Schmoe - Valvoline does not use moly in any of its passenger car oils. Maxlife was the only one that did contain moly for a time, but it no longer does.

Their fleet oils targeted at Diesels do use moly though.

[ May 29, 2003, 11:43 AM: Message edited by: MNgopher ]

 

[Bror Jace]

Lee280zx, so far so good.

Do you have any idea what you are going to run in this car on a regular basis? I have 5 quarts of Valvoline All-Climate 20W50 I need to get rid of. I can't find a machine we have that I like so little that I'll use that stuff in it.

For moderate high-performance driving and regular drain intervals (4,500 miles max) I would use one of the 15W40 fleet oils like Pennzoil Long Life or Chevron Delo400. Your engine won't labor as much as with a 20W50 and wear protection should be improved because of the improved additive package these oils (as a class) provide ... especially the Pennzoil with its ~180ppm of moly.

Of course, for real high performance driving (higher RPMs and/or oil temps) plus extended intervals, consider one of the better synthetics in 10W30 or even a little heavier.

--- Bror Jace]