High aluminum on 450C oil sample

[Ed Hanscom]

I’m currently in contract on a 2002 Sundancer 460 with 450 Diamonds with less then 300 hours. Got the oil samples (CAT lab) back yesterday. The port motor is ‘yellow’ listing ‘Excessive Aluminum content’. It shows 22ppm, whereas the starboard motor shows 10. According to the Cummins dealer, all of the other numbers (on both) are OK.

According to the seller, the oil was changed in October and has approx 30 hours on it.

How concerned should I be? The mechanic is recommending a flush, then new oil/filters, then 10 hours of operation under load then re-run the samples. He’ll also cut open the current oil filter and look for particles.

Not sure if the seller will be willing to go through that. If he instead wants to reduce the price, what would be a reasonable worst-case scenario?

The sea-trial is scheduled for next week. Don’t think I want proceed if this Aluminum level could mean a major rebuild.

Thanks for your help with this. I coming out of a boat with gas motors, so this is new territory.

Topic

[Fireisland1]

Offer to pay to have the IC’s serviced. You will need to do it anyway. If you don’t like what you see, either walk or renegotiate. Owner wins and you don’t get stuck.

[Philip]

Engine Temp is only the small part of the aftercooler equation – you can monitor that with a gauge.

The big part of the aftercooler servicing equation is sea water getting past the end cap o rings and spraying the inside of your engine. There is no gauge to monitor that so the only option is to remove the cooler from the engine and service the cooler on the bench with new ones rings after cleaning the mating surfaces and using lots of grease,

As to the question about factoring the service into the purchase – anything can be negotiated….

Phil

[Ed Hanscom]

Sea-trial was today. Fully loaded with fuel (400 gal), water (100 gal), and 7 adults. WOT was 2700 RPM, speed was 24 Knots, temp was 170. Ran for 15 minutes at WOT per Cummins mechanic.

Also, the tachs had been changed by the previous owner, so the actual engine hours are about 900. To me that is actually better than 300 as they haven’t been just sitting for as long, no?

Vessel has no way to monitor fuel burn, so not sure on fuel flow rate. How best do we test that?

Finally, owner is unaware of any aftercooler service. He has his own “guy” that takes of the engine room. Based on temp readings and chipped paint around the flanges, I’d say someone has at least rodded them in place. As they were within spec, nothing will probably be listed in the survey. Would it be reasonable to ask for a service as part of the final price negotiations? Or would it be OK to run as is for a while and see how it goes?

Thanks again for the help…

[Ed Hanscom]

Thanks, Tony. Did a lot of reading on your site. Greatly appreciate you sharing all of that.

Sounds like we’ll proceed with the sea-trial. I’ll learn a lot more about the engines then (Max RPM, fuel burn, Temps, etc).

Not sure when the aftercooloers were last serviced. I’ll ask the seller, but if it has been a while that will show itself on the sea-trial, no?

Thanks again for your help…

[Tony Athens]

Concern yourself about what really matters ( and probably the “why” on the samples).. When was the last time the aftercoolers were removed from the engine and serviced on the bench per my protocol?

17+ years of “Marine Age”…………………

Learn this term and learn about the highest maintenance item on any high performance marine engine in this class, “ANY COLOR”————A “Saltwater Cooled Aftercooler” made from “mixed metal alloys”..

[Ed Hanscom]

Trying again… here are the reports…

[Ed Hanscom]

By the way, attached are the oil sample reports…

After digging deeper into the forum, it seems as though 22ppm is not that high relative to others. Why would this cause it to be flagged ‘yellow’?

[Author]

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