Cam Pics - What do you see?

[Skates97]

A friend is looking at a Mooney, O-360. It flew about 10 hours a year since a prop strike/repair in 2003. Then 2018 and 2019 about 80 hours per year. These pics are from early 2020 when a cylinder was replaced. I don't know enough to know what I am looking for or not looking for but told him I would post these up for you all to pick over...

[GeeBee]

Corrosion at the top of the lobe. Stick a fork in it.

 

 

[Skates97]

7 minutes ago, GeeBee said:

Corrosion at the top of the lobe. Stick a fork in it.

 

 

In the second picture? That's what I was wondering or if it was reflection off the side of the case.

[GeeBee]

First, second and third picture. Lobe on the right.

 

[Lionudakis]

I see corrosion on a lobe, factor an overhaul into the price. It might last a while, or not. 

 

AP/IA and M20C driver / owner

[Andy95W]

Richard- I see what you mean, I've made some notes on the photo.

It might come down to how many hours are on the engine, and just run it until the cam spalls.  Then either overhaul or replace the camshaft and install DLC lifters.

 

[Lionudakis]

This looks ugly from the pic.  I’m with Andy, run it until metal shows up, then tear it down. 

[GeeBee]

Trust me from experience, it will start making metal pronto.

I got a Lycoming cam out on my workbench in the basement to remind me.....with a red tag on it.

 

 

 

[Andy95W]

53 minutes ago, GeeBee said:

Trust me from experience, it will start making metal pronto.

I got a Lycoming cam out on my workbench in the basement to remind me.....with a red tag on it.

 

 

 

@Lionudakis and I are both A&P/IA's, so some experience as well.

A cam like that could go 50 hours or 250 hours.  If it was forged before 1995, it's a lot more likely to go longer.

I'd cut open the oil filter every 25 hours and check the suction screen every 50.  Every annual I'd check valve lift like it mentions in Lycoming SB 301B (normally a 400 hour inspection).

[Skates97]

Thank you for the education guys, much appreciated. 

[jetdriven]

The left set on this photo looks like a spalled lifter and accompanying cam damage. Look at those carefully. 

[Yetti]

Can you find out what year the cam is?

[Skates97]

41 minutes ago, Yetti said:

Can you find out what year the cam is?

Serial number of the engine is the same as the original serial number in the engine logbook when it rolled out of the factory. Only thing I can find is a major overhaul in 87 but do not see it mentioned in the entry that the cam was replaced. There was a prop strike in 2003 and the logbook entry specifies the work done but again nothing about a cam replacement, so I would say it is from 1968?

[MB65E]

Looks like that second picture is the worst looking one in the bunch. It’s Not unsafe to keep running it and roll the dice. Be prepared for at least a new camshaft. 
Glad they took photos. That alone is good form and worthy of working with the guy. 
-Matt

[Skates97]

24 minutes ago, MB65E said:

Looks like that second picture is the worst looking one in the bunch. It’s Not unsafe to keep running it and roll the dice. Be prepared for at least a new camshaft. 
Glad they took photos. That alone is good form and worthy of working with the guy. 
-Matt

There was a cylinder replaced recently, he took pics of the cam while it was off. Seller has seemed very straight forward and forthcoming, but I think this is enough for my friend to keep looking. He's not in a hurry to buy, and as I've told him the only thing worse than not having a plane is buying the wrong one.

[ArtVandelay]

Serial number of the engine is the same as the original serial number in the engine logbook when it rolled out of the factory. Only thing I can find is a major overhaul in 87 but do not see it mentioned in the entry that the cam was replaced. There was a prop strike in 2003 and the logbook entry specifies the work done but again nothing about a cam replacement, so I would say it is from 1968?

I recently had my engine overhauled, cam replaced, there is no mention if this in the log entry. Just generic wording about all parts being to new limits. Only accessories were listed with serial numbers. So you don’t know if it was new, or what. They should have followed the Lycoming overhaul service manual.

Notice the cam, there was no substantial metal in the filter or the oil analysis. It simply just slowly worn down. I put 700 hours on this engine after years low activity by PO.

 

 

 

 

Tom

[GeeBee]

6 hours ago, Skates97 said:

There was a cylinder replaced recently, he took pics of the cam while it was off. Seller has seemed very straight forward and forthcoming, but I think this is enough for my friend to keep looking. He's not in a hurry to buy, and as I've told him the only thing worse than not having a plane is buying the wrong one.

I don't think it is a killer. Just adjust the price. If the airframe is what he wants and he can hang a new engine on it within the budget, that is a great deal. He will have the airplane he wants with a NEW engine.  Better than buying a mid time "unknown" because you can't see inside. 

The advice here is correct. The airplane is not going to fall out of the sky. I flew a PA-18 from SEA to ATL with a corroded cam. Eventually it will start wearing enough the engine will make noticeable metal and maybe become a little anemic. In my case it generated about a teaspoon of metal. At that point I pulled it off and overhauled it.

 

[carusoam]

Go MS!

Great pics.

Great details.

Great explanations.

Thanks for sharing.

Best regards,

-a-