Oil analysis on IO-520A

[PeterNSteinmetz]

Question for the engine mechanics.

I am looking to purchase a share of a Bonanza with an IO-520BA high time engine. It is running great but is past TBO at 1843 both since overhaul and new.

Oil analysis performed for past 3 years shows some normal values for Nickel and Chromium, but higher than what is on the engine in my Cardinal. To wit:

Nickel 2018 - 11, 2019 - 10, 2020 - 14
Chromium 2018 - 6, 2019 - 6, 2020 - 8

Does this set off red flags? It is priced for the TSMOH accordingly and clearly the hours past overhaul are just a bonus.

 

[TCABM]

How well has the partnership funded an engine reserve?

 

[Radar Contact]

Are they only getting one analysis a year or is that the yearly average you are posting?

 

[schmookeeg]

No red flags.

It's not a lycoming. Borescope the jugs, check for exhaust valve leaks or jankitude. Oil Analysis isn't super helpful on these. They eat jugs with alarming regularity. I've had the best luck with Millenium Standard Cast and have run those on 3 big contis now.

 

[PeterNSteinmetz]

Thanks for the replies. In answer to some queries:

The partnership is being formed and will fund the reserve at a fixed rate per flying hour.

The values are from a single oil analysis at change with the annual. It has only been flown about 30 hours per year.

The exhaust valve in one cylinder was replaced but apparently the rest of that cylinder and others is original. Borescoped each annual with no signs of other problems.

 

[schmookeeg]

No red flags.

It's not a lycoming. Borescope the jugs, check for exhaust valve leaks or other top-end jankitude. Oil Analysis isn't super helpful or predictive about impending costs/life remaining on these. They eat jugs with some regularity. I've had the best luck with Millenium Standard Cast and have run those on 3 big contis now.

 

[Radar Contact]

The values are from a single oil analysis at change with the annual. It has only been flown about 30 hours per year.

*I am in no way an expert on this*

Over the past 5 years I always have the oil analyzed. I run 2 big bore Continentals. In my opinion it would be VERY hard to get much relevant data from only one a year…especially with 30 hour years mixed in. These reports are about trends. Subtile things can cause elevation at different times. i.e. Inactivity, indoors vs outdoors, hours/time between changes, change in oil brand, etc.

My goal is to see the trends that show up with 3-4 changes per year. I was able to catch spalling lifters before they damaged the cam lobes (could have also been done purely by bore scope down the oil filler neck). Conversely I triggered an alert for them when it was parked in FL for a few months during the paint job that went back to normal after regular mid-west flying.

Long way of saying I wouldn’t be concerned about those reports.

 

[Jdm]

You mentioned hours, but how many years has it been since overhaul?

 

[Clip4]

Fly it a few months and get a new engine.

 

[Salty]

I’d suggest to the partners that an engine fund should be jump started when the partnership forms. I’d like to see 10-15k in the fund at the start in this scenario. Odds of needing at least one cylinder soon are extremely high.

 

[luvflyin]

I’d suggest to the partners that an engine fund should be jump started when the partnership forms. I’d like to see 10-15k in the fund at the start in this scenario. Odds of needing at least one cylinder soon are extremely high.

And following through on that thought, another one soon after that etc etc. I wouldn’t go into it without the money already in place for a new/overhauled engine. If you beat the odds you can incrementally lower the monthly fees to make up for it. Or you can celebrate your good luck with goodies. Like a cool paint job, fancy interior, neato avionics, etc.