I'm looking at purchasing my 1st Aircraft a Comanche 250 and this Picture of the Exhaust Manifold (header-pipe) seems to indicate the use of Red Permatex..?
Is that Normal, or could it indicate a poor Fix of a leaking exhaust manifold gasket.

Any other oddities that might be noticed please comment.

I also Attached a photo of what looks like rubbing on the Exhaust pipe.

Thanks, Rich

I doubt that is an approved repair. It suggests that there is warping or corrosion on either the exhaust flange or on cylinder mating surface.

I received an email, but it didn't tell me how to contact you. Email me at kristin@theaviatrix.com. I think I can help.

Someone definitely likes their Permatex. It appears to be used on the line in the upper photo between the fitting and the fire sleeve right before the adele clamp. Also see remnants of it on the scat tubing in the same photo. And I would agree there does appear to be rubbing of some type on that exhaust pipe.

Tim

How uncommon is it to see such a crude repair?

Is that an indication of more problems to come?

It just doesn't seem to give me a good feeling about the rest of the maintenance and repairs.

Rich,

Kristin is tremendously knowledgeable and suggest you use her to help yourself not end up with something in which you end up spending more on Maint than flying. Comanches are wonderful planes but some have been better taken care of than others.

Well, first things first,
The tailpipe with the witness marks on it is not atypical. It highlights the design deficiencies of the original exhaust system. The whole system moves with the engine, and the cowl/engine mount does not, and thus it is not uncommon to see the evidence of some contact. It would be worth looking at what it is hitting and if the interference is stock or some modification that has introduced the interference. in the stock config the only thing keeping the headers in the muffler, and the muffler from rotating on said "muffler bearings" is the pin in the clamp. Check and make sure the clamp still has the pin attached, many are worn or missing. Realistically, if you want to fix this once and for all, get the dual exhaust system STC from APP and it does away with ALL, and I mean ALL of your concerns here.

The hose with RTV on it if just fine. It is probably a field hose with the frayed end of the firesleve "cleaned up" with the some RTV. Its an easy and safe way to finish the hose.

RTV on the exhaust flange...time to investigate. It could be a bandaid fix for an eroded exhaust port. If it has already been faced in place, the only fix is to pull the cyl, weld and reface. It also might just be residual RTV used in the assembly process. This is a typical method that some mechanics use as a third hand to keep the exhaust gasket in place while the stack is fitted. Keeping three gaskets up ther while maeuvering the stack with two hands is not real easy...so with that said, even the worst case is not a deadly error as the fix will probably work for 25-50 hrs before it starts leaking again if it is eroded, but it wont get any better and you are looking at about $150 bill from a cyl shop plus remove and install. If it is just assembly dumb dumb, then it will last a long time and is just fine.

-Zach