Thoughts on IO-360 compressions

Morne

Morne

Line Up and Wait
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Morne
If you we're considering buying a plane with a Continental IO-360D that had 4 of 6 cylinders in the low 60s last check what would your thinking be? Just factor in topping it when you buy it? Replace all cylinders just to be safe?

The time is virtually at TBO, not that it is a death sentence. Never been topped or had a jug pulled. Oil analysis and trends from last 5 oil changes look good.

Thoughts?
 
Has the engine sat for while? If so maybe a quick boro of the cylinders to see anything. Run it for a while and see if they come up and while you are at it try and nail down where its coming from: rings, valves etc... Chances are good you will be changing jug so as long as you can price that in.
 
It ain't broke so don't fix it,

Don't over pay based on the engine time either.
 
I understand that Connie compressions are routinely lower than Lyc and its still within specs. Not sure in this case.
 
If its still making power go with it. But im sure you understand that it could be a sign that something is getting a bit tired.
 
Skylane81E said:
You understand right.


Did you find your 337 Morne?
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Well yeah, but the seller is asking over Vref. He's willing to trade for a 182, like mine, but right now that would be upside down (Vref shows my plane valued much more than his).

Before I start really talking turkey with the seller I want to know just exactly what sort of cost I should factor in for that engine. For instance, I might meet his asking price, or trade straight up, if he pays for topping it and 4-6 new cylinders.

Someone elsewhere mentioned that pulling jugs, honing and re-ringing is fairly cheap insurance that the engine you're buying will behave for awhile. I think that's the minimum in this case.

How do you, or more correctly an A&P, check for leakage around the valves?
 
Just kind of comes down to finding where the air is leaking. If its out the breather you can bet its rings. If not then its got to be the valves. Narrowing it down to between the two can be tricky.
 
I would negotiate price down based on the compressions and whatever factors and start thinking about what you want to do for a new engine.

Does the Continental 360 have the same SB that allows for lower compression numbers? We definitely had that on the 310, a few were down in the low 50s but still legal.
 
hindsight2020 said:
Why are you getting rid of the 182?
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I was always destined for a twin. The only question was which one and when. I got my instrument rating, so the only thing left is my multi-rating.

I started to figure that I should consider buying while the twin market is still in the dumper. I generally like how this bird is equipped, and the other engine is lower time, so the only reservations left were this engine and the asking price.

I had originally thought to wait another 3.5 years to buy a twin, but who knows where the market will be by then.
 
If you find a good plane that you like and can come to good terms on it, go for it.

This is a straight 337 and not a T337 or P337 I'm guessing?
 
Ted DuPuis said:
This is a straight 337 and not a T337 or P337 I'm guessing?
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Correct. I decided that for an Ohio boy I don't need either turbocharging or pressurization in a twin. NA gets me high enough to clear the mountains I cross most often and paying more for maintenance is not high on my list.

I understand it was the P variant that gave the Skymaster its bad name with regards to maintenance bills.
 
Morne said:
I was always destined for a twin. The only question was which one and when. I got my instrument rating, so the only thing left is my multi-rating.

I started to figure that I should consider buying while the twin market is still in the dumper. I generally like how this bird is equipped, and the other engine is lower time, so the only reservations left were this engine and the asking price.

I had originally thought to wait another 3.5 years to buy a twin, but who knows where the market will be by then.
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Oh ok, gotcha. I'm in the market for a 182 and find it to be an excellent all-around mission airplane and it seemed it was giving you pretty good service. Sounds like you're looking for the step up in mission set.

Personally I don't think the GA market is going anywhere for a while. I don't foresee airplane financing becoming the silliness it was in the mid 2000s. Either way, life's too short to wait to fly tomorrow if you can afford it today. Good luck with the airplane search!
 
I think that's a smart move for someone living in the flatlands and staying east of the Rockies. As I've said elsewhere, I've found a naturally aspirated twin works well for my flying (95+% of which is in that range) and provides sufficient OEI performance for what I need.

Turbos and pressurization will add to MX without providing a significant benefit in your case.

Wonder if RotorAndWing will chime in, he had at least one 337.
 
Yeah, I've only flown the rockies once and you can compensate by choosing your route carefully. If the 182 could make it to Southern California and back then this bird certainly will be able to as well, on the rare chance I ever need to do that trip again.

@Hindsight2020,

The 182 is an EXCELLENT all-purpose platform. I am very satisfied with my plane and the service it has rendered. But ultimately, when I haul my family over open water, night, IMC and/or rough ground I simply gotta have a twin. That's my bag. You should take heart in the capability of a 182, they truly are great haulers and dependable birds.
 
Morne said:
Well yeah, but the seller is asking over Vref. He's willing to trade for a 182, like mine, but right now that would be upside down (Vref shows my plane valued much more than his).

Before I start really talking turkey with the seller I want to know just exactly what sort of cost I should factor in for that engine. For instance, I might meet his asking price, or trade straight up, if he pays for topping it and 4-6 new cylinders.

Someone elsewhere mentioned that pulling jugs, honing and re-ringing is fairly cheap insurance that the engine you're buying will behave for awhile. I think that's the minimum in this case.

How do you, or more correctly an A&P, check for leakage around the valves?
Click to expand...


How much do the planes differ in value?

On the leakage, as noted above breather is rings,

Air filter is generally intake valve and tail pipe is exhaust.

If there is significant exhaust valve leakage you may want to consider yanking them at a "passing" number.


Regardless if you can negotiate the deal from the view that the jugs are dead DO IT, then you can treat any life left in them as gravy.

Personally I think if it is a few hundred shy of TBO and the exhaust valves aren't leaking then odds are fairly good they will make TBO. Then you get to decide how much you trust the bottom end:wink2:
 
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