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Aside from some of the things already mentioned, I see no provision for CARB HEAT in the forward baffles or left hand muffler!

The vertical baffling up front that directs airflow up and over the cylinders is missing. Engine cooling is compromised.

There is a firewall patch on the lower pilots side indicating possible previous damage and affecting firewall thickness. Similar reinforcement (thickness) should have been installed at the other 4 mountings (5 mount bolts on a '60) to assure proper engine mounting.

The pre '64 cowling isn't shock mounted, Bengie, but the tinnerman clipnuts driven between the skin and the underlying angle extrusion (likely because of stripped blindnuts) may compromise firewall sealing and introduce corrosion.

Where are the steering rod boots?

I believe the breather hose is SAE automotive hose (I could live with that, temporarily.)

What else have we missed?

Bingo, WTF

Another great catch Bengie.

Here is the cowling with the cut out for the left tailpipe

I've been safety-wiring over 40 years, 31+ years of that on a daily basis. My safety wire is "pretty"! It's by the book! But, I still make mistakes (rarely, but I make them). Cut it off and re-do it! No big deal!

I can buy into that but baffling and safety wire installed incorrectly. If thats what happening on the outside, what happened on the inside?

Carl, The logs show that the fire wall, engine mount and the nose strut were replaced in the late 80s. There is nothing in the engine log at that same time although the engine and airframe were married in 1962. Also some work on the main gear box was performed. The latest overhaul was completed in Oct 06. The nose strut was rebuilt at the same time. The engine has been sitting since then with nothing covering the carb inlet and nothing in the lower plug holes. When I removed the upper plug cap to do the bore scope I could see dirt suspended in the oil in the cylinders. There are yellow tags for the case, crank, cam and lifters and a logbook entry for the overhaul but nothing to show the part numbers for bearings, seals, ect? I was told that the cylinders have new valves and guides but there is no paper work to support that. Having said all that I believe the engine will need to be disassembled. Yours or anyones thoughts?

I've known of people simply draining and reservicing engines that have sat for decades with no ill after affects ..... but I certainly do not recommend that practice!

Some will tell you that the engine must be disassembled and minutely inspected, regardless! That will obviously give you the best piece of mind, but a lot of money has been wasted by many people who found nothing wrong with their engines after complete disassembly.

I take a more middle of the road approach, which I think makes more sense, too!

Assuming you are satisfied with the logs and sign-off, the question is how well was the "fresh" engine protected by the assembly oil. The rod and main bearings can remain wet for decades from capillary action, depending on the oil used, but do not disturb the crankshaft, just yet! Drain and discard the assembly oil, and remove the remainder of the accessories, the oil sump, and valve covers! Do a good visual and internal borescope inspection of the crankcase, geartrain, and cylinders looking for any sign of corrosion. Good decisions will depend on your judgement. Very spotty (quarter sized or so) surface corrosion (powder) on the external crankshaft throws, or similar thin spotty corrosion on other visible iron components are acceptable on non load bearing surfaces (most active engines have some of this anyway). Iron oxide "fuzz" coating any one component, gear teeth, or load bearing surfaces is not acceptable without further removal measures and closer inspection. Any but the lightest rust on the apex or ramps of the cam lobes may be cause for engine disassembly. Don't forget the face of the lifters. If you can rub the thin iron oxide powder off with a dry rag and find nothing more than slightly discolored metal, it's likely still good! If nothing other than spotty minor surface rust (powder) is found inside the crankcase, wash or spray all oil-wetted components with mineral oil and let it drain. Remove, inspect, oil, and reinstall the safety relief valve. The "short block" is done.

No doubt there will at least be some minor surface corrosion on the steel cylinder walls. This is a judgement call as above. Quarter sized obvious surface rust spots can generally be ignored, and will disappear soon after starting. These can form within a few days even on "active" engines. Remove any that you can reach, spray the cylinders with mineral oil, and let them drain. Larger areas of corrosion, or that may hide pitting, will have to be examined more closely, with the cylinders removed. Pre-oil the engine oil passages under pressure with mineral oil before turning the crankshaft for cylinder removal. I have had very good success cleaning and rehoning otherwise good cylinders displaying considerable amounts of surface rust. Wipe away as much rust as possible with a dry rag, and if no pitting is revealed, re-hone them just enough to knock off the remaining rust and reestablish a cross-hatch pattern. A little etching (not pitting) left from the rust does not hurt anything, and will wear away in a few hours of operation. Re-measure the bore and piston for proper clearances before reassembly. I've reused the same (new) rings without removing them from the pistons, with no problems, but if in doubt or they appear stuck, remove or replace them now! Replace any disturbed gaskets and seals, which cost nothing by comparison to replace. Oil and reinstall the cylinders and finish final assembly and installation. Again pre-oil the engine and fill the sump with mineral oil before attempting a start. With a properly pre-oiled engine, oil pressure should respond almost immediately. Do not exceed idle if idle can be maintained, then shutdown and drain and refill the sump again once the oil has had time to warm. Inspect the drained oil for any sign of metal or other contamination. You're ready for the initial break-in and adjustment runs.

I actually do have some before and after shots of cylinders I've cleaned up and placed back into service. My return to service experience ranges from A-65's to R-2800's, with no failures. If anyone knows of something I've forgotten, or have a better method, please jump in and let us know. I'm still learning, too!

That paint job on the engine would make me pretty suspicious...

Reg

What safety wiring are y'all talkin' about? My old eyes just can't make out any. In any case, like Carl says "ain't no bid thing to redo it." The wet vacuum pump needs an air oil separator and the breather hose on those installations go up and over to the separator--nothing wrong there. For those with the M20 separator on the dry vacuum pump aircraft, they recommend rerouting the the breather line over the engine exactly like this installation. They also recommend putting insulation on the line. Is that an automotive hose or insulation? Again, these poor eyes of mine can't tell from the photo. The baffles are different on different models--I can't tell if these baffles are wrong, maybe they are or maybe they're not. The carb heat isn't connected 'cause there's no carb or air box installed--the fitting from the portside muffler is there for the scat hose. About the only thing to give me pause from these pictures is what Carl mentioned concerning the reinforcement on the firewall. I certainly wouldn't consider tearing a newly overhauled engine apart because of some discoloration/dirt in the oil. I'd drain the oil and break in the engine and start an oil analysis program after break in provided the engine runs okay. IMHO, this looks like an excellent project aircraft with most of the heavy lifting accomplished.

I think that's the problem here - a big length of safety-wire between two bolts, obviously pulling one in the 'loosen' direction. Right on the front of the engine, plain as day, and yet the mechanic didn't cut it off and re-do it. Was he apathetic or ignorant? If he can't get such a simple task right or be bothered to fix it when wrong, what else might be lurking, sight unseen?