generator oil analysis?

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BlindHog

Senior Member
Joined
Nov 7, 2014
Messages
128
Location
USA
Vessel Name
Southern C's
Vessel Make
Cabo 31 Express
Looking at a 5kw westerbeke diesel generator and the oil analysis came back with aluminum at 13 PPM. All other numbers are within range and generator has under 1400 hours. Any cause for concern?
 
I get a "universal average" from Blackstone Labs on my oils analyses, and that's their average for all engines of a type they test. You don't see such a number on the report?
 
There is not an average but google showed under 12 as normal range (assuming my search was good) so I’m now thinking that 1 ppm could be a test analogy or even the sample tube scraping the bottom of the oil pan? No other items showed outside of the normal ranges. I’ve only seen a couple of oil analysis so was hoping to tap into the collective TF knowledge. Thanks!
 
Did you look at the oil?
A lot depends on how clean the oil looks. If the oil is almost new, 13 PPM is horrible bad. If the oil is black on the dip stick, maybe not quite so bad. For reference, my 9 KW Onan averages 2 PPM after 100 hours. The universal average for that motor is also 2 PPM.

Ted
 
My rebuilt 3.5 KW Nextgen generator is right now sitting in the bed of my pickup awaiting the warm bodies to wrestle its 185 pounds into the engine compartment (my boat's engine's living quarters are too small for me to occupy the space so not a "room"). It suffered from a crap exhaust hose installation by Mainship which ensured water would run back into the engine. Aluminum content for the last 11 hours after oil change was 19, BUT in the 44 hours of operation after a previous oil change the reading was 359. So how many hours did this oil have on it before you sampled it? If it was, say, a hundred, you may be just fine. In the end, my little one lunger just had so much corrosion at the valves and seats that it could not generate the compression to start. Hopefully, for me, the nightmare is over with the redesign of the exhaust.
 
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Thanks for the replies! Just to be clear - I am the seller and the buyer sent the report. I had the electrical side rebuilt by broward armature in April and we installed the generator back in the boat after it had been out and sitting for several years. This is the first oil in it since it’s back in the boat and probably under 30 hours. Starts and runs fine with zero issues. It did shut down once because the new impeller bite the dust but other then that it’s been running fantastic. Maybe change the oil, run it for a few hours and retest?

IMG_8968.jpg
 
Thanks for the replies! Just to be clear - I am the seller and the buyer sent the report. I had the electrical side rebuilt by broward armature in April and we installed the generator back in the boat after it had been out and sitting for several years. This is the first oil in it since it’s back in the boat and probably under 30 hours. Starts and runs fine with zero issues. It did shut down once because the new impeller bite the dust but other then that it’s been running fantastic. Maybe change the oil, run it for a few hours and retest?

View attachment 141387

I would opine it needs enough hours to get a comparable retest, at least as many as it had on the oil before the last test.
 
Thanks for the replies! Just to be clear - I am the seller and the buyer sent the report. I had the electrical side rebuilt by broward armature in April and we installed the generator back in the boat after it had been out and sitting for several years. This is the first oil in it since it’s back in the boat and probably under 30 hours. Starts and runs fine with zero issues. It did shut down once because the new impeller bite the dust but other then that it’s been running fantastic. Maybe change the oil, run it for a few hours and retest?

View attachment 141387

Clean oil tests mean nothing. I would view that as high, but not sure I would tell the buyer when it was changed last. One test means little, several tests over a period allow you to spot a trend. What’s the buyer asking you to do?

Ted
 
That looks like fresh oil with high aluminum, and high aluminum for its hours.

My guess? It's breaking back in after the years of not being used. Maybe some oxides are being polished off. Maybe things are reseating. I bet it cleans up.

I'd be worried about that coming out of nowhere on an engine. But, even then, unless there was some recent service history to give a hint there wouldn't be much to do other than to double down on oil change and tune up items. It could be a lot of things, most hard to get to.

I'd keep testing it to see if it goes back down. If all is running well, I bet it will. But I can't promise that.
 
Clean oil tests mean nothing. I would view that as high, but not sure I would tell the buyer when it was changed last. One test means little, several tests over a period allow you to spot a trend. What’s the buyer asking you to do?

Ted

With those numbers, including the soot that low, it is pretty clearly pretty fresh oil.
 
Post the ENTIRE report in PDF. Little snippets or summaries are often of little help. They miss a lot.

Which test lab did you get the report from? Both CAT SOS and Blackstone show averages as already asked about as do others I have seen. Was there a lab opinion offered? Often the opinions are pretty cursory but it is worth finding out.

I have used Cat SOS for 30+ yrs.

As mentioned the aluminum may come from having sat for so long and it may settle down , not rise, as the engine operates. Of course that will take another test of two.
 
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If normal is 12 and you have 13 I would not worry about that 1 ppm. I doubt measurements are that accurate.
 
It could be from the oil filter, they are made of aluminum.

pete
 
Who took the sample? Did they drag the sample tube across the bottom of the oil pan? Was the lab given the lube time? Did they flag this as high?

If, for instance, the lab was told the oil had 0 hours (or the space was left blank), then almost any amount of contamination is too high, and flag worthy.

Oil analysis (and how to properly sample)

Oil analysis in detail https://stevedmarineconsulting.com/wp-content/uploads/2014/03/FluidAnalysis143_Final.pdf
 
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