Soft Cylinder 48/80: Safe to Fly?

[mahlon_r]

Originally Posted by Dave H.

Bret,

The plugs are dry and this engine never fouls plugs.

There is a lot of oil in the photos. I should have mentioned that the engine was run (lean) on the ground for total of about an hour on the ground before the scope. 1/2 hour before the compression test, and another half hour today to give me a warm environment to work.

-Dave

If it were me, I would fly it for an hour and recheck. If still below 60/80, I would fix it before further flight.
Good Luck,
Mahlon

[Jesse]

Anything Mahlon recommends I would stand behind. From the sounds of it this has been going downhill for some time, which means an hour of flight probably won't help much, but it is worth a try.

[Flyingleap]

I've seen enough. Pull the cylinder before more potential damage can occur.
Cut the filter, look for metal, pull the bottom screen for the bug chunks, and look at the cam, lifters.....now. If I saw this it would be off right now and looking at everything inside I could see with just one jug off.

But that's just me.
John

[Avengerboss]

After reading all the facts, the unknown engine condition and the degrading of the cylinders over short hrs, I'd pull the engine and have it majored before its to late.
To many factors going on here.

[RV Jerry]

Do your self a favor and at least pull that cyl.now you will save money in the long run also inspect condition of engine while removed . If it were me I would consider additional work giving history of engine

[vic syracuse]

Seriously, you have already been given a lot of great advice, and I don't mean to pile on in any way. The question you have to ask is if it is potentially worth risking the airplane, and perhaps life and limb, for the price of a cylinder?
I know it can be intimidating to replace a cylinder, but these engines are really simple, and you will realize that once you get into it. A cylinder can be swapped in a day or 2, even by a novice, and you will look back on it and realize you are less stressed and probably even enjoyed the learning experience.

Vic

[Kevin Horton]

Originally Posted by Dave H.

BillL,

Thanks for your insight. Pulling a jug for overhaul may not be a big deal for you, but I don't think I have the confidence to do it myself. I've rebuilt auto engines but that is different.

You don't have the pull the cylinder yourself. Hire an experienced A&P to do the work, with you as his assistant.

[PCHunt]

Two articles by Mike Busch that might be germane:

https://www.savvyaviation.com/wp-con...-be-afraid.pdf

https://www.savvyaviation.com/wp-con...8_teardown.pdf

Probably wouldn't cost all that much to have Savvy Analysis review the issue.

[KatanaPilot]

I am not an A&P and have very little experience with engine overhauls.

A lot of good advice has been provided here already.

However, as an airline pilot I often view my GA flying through the lens of "could this affect my license." The FAR's (91.7) are pretty clear about the requirement of the PIC to make the determination of the airworthiness of an aircraft.

Just the fact that you have come to this forum indicates to me you have concerns and/or questions about the airworthiness of this particular airplane. So as an outsider looking in, I don't think you would have much in the way of a defense of flying this airplane in it's current condition. I know I wouldn't, but I am generally very risk averse. That has served me pretty well so far in over 40 years of flying and 31+ years at the airlines.

Please don't let your desire to fly this trip turn into another GA incident/accident. There are enough of those already.

[YellowJacket RV9]

When in doubt, think "how would this sound in the accident report?"