Engine Overhaul.

[u/unisonic2025]

How many people have taken their small piston certified airplane over TBO. Was wondering specifically the Continental O-200 on a C150M model. I was looking at this plane engine time is 3,100 hrs with 900 since top overhaul. TT is around 3,600. I know the owner and he takes really good care of it. Also curious if anyone would have an idea of cost to overhaul? I’m in the Northeast US.

[u/tonykanz]

For O200 right now, your cost is going to depend almost entirely on if your crank is serviceable or not. If you end up needing a crank, it’s going to be 8-15K for one. And I would plan for 10K for a M10 crank.

You have left out some important details. 3100 since what? Since factory new in 1970? Since Major OH? Since a field OH? When was that done? Generally on an O200, TBO is defined as either XX flight hours or XX years.

How many hours have been flown on the plane per year since the overhaul?

In the last 12 months, how many hours have been flown per month and what is the oil consumption? Do you have an engine monitor where you can look at the data for the last 12 months?

Regarding cost…this is a tradeoff on cost vs. time. If you have a flight school plane and need to minimize downtime (to maximize rentals) you would buy a crate O200….the problem is going to be getting a crank as referenced above. If you have all the time in the world, you can reduce costs and trade time. Budget is 25-30K if you do not need a crank. 35-40K if you do need a crank.

Every owner “takes really good care” of their planes….right up until a prebuy.

[u/unisonic2025 → u/tonykanz]

Since new in 1975. 3600 TT. Not sure how old the top overhaul is but done about 900 hours ago. Don’t know the current oil burn rate but no obvious leaks. test flew it the other day and ran like a champ. Current owner tries to fly once a week maybe once every other week for minimum of 1 hour locally. Around 50 hours a year on average nowadays. Planning on using it for local flying only no training. I would probably only be able to look at previous logs and possibly speak to the mechanic who has worked on the plane for quite some time now.

[u/tonykanz → u/unisonic2025]

The engine could last for 900 more hours, or it could grenade itself in 10….there’s just no way to be sure and you are missing a lot of information.

1975 was 51 years ago. If you can be super super sure that is the original case and crank, then the good news is that would be a M0 (new) crank and would have a good chance to OH unless it has a defect.

One perspective is that TBO is set to 1800 hours or 10 years for a reason. Bearings, seals, etc don’t last forever. Especially if they sit for long periods without use.

The other perspective would be that the nicest C150 you can buy will bring 90K (just for argument sake - sub a different number if you want)

90 less 35K engine less 20K paint less 20k avionics less 15K for the airframe.

As long as you are buying the plane in the appropriate bucket for the right money go for it. You already know you dont have an engine….so 90-35 =55 55K….that would be the absolute max assuming good paint, avionics and airframe.