Prebuy advice/2004 M7-180AC

[keb0]

Hello, looking for advice regarding prebuy inspection of a 2004 M7 located in the midwest. I live in AK so trying to do this from a distance if possible. It has 437 TT, A and Eng., and appears to have been well kept in a heated corporate hangar, at least the past 15 years. Two owners, look to have treated the plane very well. I'm not a mechanic and seeking advise on what I should insist on for the prebuy other than the basic checklist. Comps are mid 70's and similar. It's headed into annual next week. Should I have a cyl pulled and inspect the cam? Would you expect an 18 yo 0360 to go a while? Thanks, Kenneth

 

[Bell206]

I'm not a mechanic and seeking advise on what I should insist on for the prebuy other than the basic checklist.

First, I'd sit down with the mechanic you plan to use in AK to maintain this aircraft and get his input. If not he'll definitely be the first person to tell you where you screwed up on the prebuy and how much it will cost to fix it. Good luck.

 

[keb0]

First, I'd sit down with the mechanic you plan to use in AK to maintain this aircraft and get his input. If not he'll definitely be the first person to tell you where you screwed up on the prebuy and how much it will cost to fix it. Good luck.

Yessir, just located a local guy and showed him all the available info. He thinks it looks great so far. Thanks

 

[Stewartb]

I doubt the seller will allow you to pull a cylinder. I know I wouldn't. Have your inspector do his normal inspection on the engine and the "pre buy" should focus on airframe.

To the engine? It may be perfect and it may be on its last legs. That's true of any engine with any number of hours. There's nothing in the engine or airframe that can't be fixed. All you can do is recognize what items exist and have squawks corrected or negotiate a compromise with the seller. That plane averaged 22 hours a year since new. If all those hours were in the first year and It's sat since? Chances of corrosion in the engine are higher than if it flew regularly. Try to sort out the pattern of use and negotiate your position with the seller if you feel the need. Unless he's totally oblivious he'll be familiar with the concern.

 

[keb0]

I doubt the seller will allow you to pull a cylinder. I know I wouldn't. Have your inspector do his normal inspection on the engine and the "pre buy" should focus on airframe.

To the engine? It may be perfect and it may be on its last legs. That's true of any engine with any number of hours. There's nothing in the engine or airframe that can't be fixed. All you can do is recognize what items exist and have squawks corrected or negotiate a compromise with the seller. That plane averaged 22 hours a year since new. If all those hours were in the first year and It's sat since? Chances of corrosion in the engine are higher than if it flew regularly. Try to sort out the pattern of use and negotiate your position with the seller if you feel the need. Unless he's totally oblivious he'll be familiar with the concern.

Thanks, besides the cylinder comment, that's similar what my local guy said. I just met this mechanic and now in the bush, so looking for as much info as possible. Thank you Sir. Appreciate it. kb

 

[Jim K]

Find someone with a good borescope. You can see a couple of the cam lobes going in through the oil filler, and get a good look at the valves and cylinder bores. Enough to tell you if there's corrosion.

When I bought my plane, the engine was about 20 years and 600 hours smoh. I wound up having an iran a year ago due to losing all my oil in flight, and when they opened it up it still looked new inside. Years and even hours smoh doesn't matter nearly as much as the way it was operated and stored, particularly lengthy periods of inactivity.

@rwellner98 .... you've bought two Maules (that I know of)... what else should the op look for?

 

[rwellner98]

@rwellner98 .... you've bought two Maules (that I know of)... what else should the op look for?

Maules eat exhaust systems. They crack frequently enough to be notable. So be sure to have someone do a very careful inspection of that.

Make sure you have someone comfortable working with fabric. Not everyone is anymore.

Other than that, IMO, a plane is a plane...

Use strong ropes when you tie down...

 

[Stewartb]

FWIW my old neighbor owned an M5-160. I'd never heard of an 0-320 in a Maule before that. We have plenty of Maules in the neighborhood and that 160 hp airplane is still the best looking Maule I've ever seen. And it's been tied down outside in Wasilla for many years.

 

[keb0]

Appreciate the replies fellas. Plane is going into the shop for it's annual/prebuy tomorrow. I spoke to the head mechanic, who has done a couple of the past 8-10 annuals that their shop (Revv Aviation, Aurora Ill) has done. What he remembers off the cuff is it's extremely clean, but it doesn't fly much (obviously). Time is pretty evenly spaced throughout the lifetime of the plane, 19 years, so no big gaps in usage, and no lapses in maintenance or annuals. No damage history...they will look inside the rocker covers for potential corrosion, not sure if they can see the cam through the oil filler yet.

 

[keb0]

 

[Magman]

I can’t figure how you could see Cam on 4 cylinder?

 

[keb0]

I can’t figure how you could see Cam on 4 cylinder?

Me too, apparently it has been stated that you can put a borescope through the oil filler on a continental and inspect the cam, but I have not heard that stated on the Lycomings...all I have ever seen done is removing a cylinder for that access. Again, I am not an A&P or claim much knowledge; I just fly em, and attempt to learn what I can along the way.

 

[Jim K]

I guess I'm not 100% sure about a 360, but I can see a couple lobes on my 540 through the oil filler tube. It takes a small borescope with a flexible head. I have a "Vividia Ablescope". The filler on the 360 in the Archer I used to fly looks identical to the one on my plane, so I was assuming they're the same.

 

[mandm]

437 hours usage in 20 years is not taking good care of the airplane. In a perfect world, you’d want someone who is flying it considerably more, complete logs and NDH.

So how many hours has she flown every year for the past 5 years and what were the compressions? What mx was performed on the aircraft?

I would hire an independent mechanic for a prebuy, one who hasn’t worked on the airplane before. A mechanic who signed an annual cannot say oh it’s crap, that’s admitting to neglect.

What I would be looking at is recent hours flown, check flightaware (I prefer someone who is doing xc flying vs only an hour in the pattern), I would pay for an oil change and cut the oil filter and get it analyzed (of course not if they just did an oil change / annual), are those original cylinders? If so hopefully compressions still mid 70s + and you can fly her another 500 hours then do 4 new cylinders when needed.

Age wise, everything is not too old, you can check the small stuff tires brakes etc but more importantly does she have a good starter alternator adsb LED lights/beacon. Remember to check both day and night equipment / lights, the night stuff was missed in my prebuy.

18 years old engine is not a dealbreaker, mine is much older and she is still flying strong. I have an IO360. I’m hoping to get a few more years out of her too.

 

[rwellner98]

I would hire an independent mechanic for a prebuy, one who hasn’t worked on the airplane before. A mechanic who signed an annual cannot say oh it’s crap, that’s admitting to neglect.

Decent advice for sure. But, FWIW, Revv has a pretty good reputation in the area. I wouldn't be concerened if it were me.

 

[keb0]

Decent advice for sure. But, FWIW, Revv has a pretty reputation in the area. I wouldn't be concerened if it were me.

Thanks for the input; I have heard positive things regarding them also. That's certainly a plus. kb