C-85 Oil Pressure

[jc pacquin]

My remark on "Yellow Tagged" Was verbatim from the magazine "Light Plane Maintenence" which I subsribe to now and then. Many good tips! I had a prop gov. for my Cessna 195 rebuilt by a company who sent it back painted (real nice) and yellow tagged. I would have had no idea how to check it. Installed it. It was worthless. JC

[joea]

JC,

Things like prop governors, mags, carbs and so on cannot be tested very easily out in the field. You really need a bench to do this and thats why in the past we have trusted yellow tags. Now it seems that you cannot trust people as much as we did in the past so things like this are surfacing...

Joe A

[Paul Agaliotis]

Jc,
The term "yellow tagged" gets thrown around alot. The tag is used by the installer to make sure the part has been checked to a specific set of measurements or tests. With your governor it could be bench checked when recieved and if it performed correctly to specification it can be yellow tagged and returned. If it got a complete teardown and rebuild it would also be returned with a yellow tag. Only the work orders will have the detailed information.
Many engine parts can be at max limits and still be yellow tagged. If these parts are used in an engine it called a serviceable engine. If the yellow tagged parts meet in new limits it is called an overhauled engine.
Just because it has a yellow tag doesn't make it good part. It can be a few hours from the junk pile, but, at the time of inspection it met specification.
Paul

[MikeB]

Work orders should be written to reflect the actual maintenance and repair performed, parts replaced, etc. As a former shop manager I can tell you many techs will write the bare minimum if you let them. It's either they're lazy or don't want responsibility for their work. I've had work orders come across my desk that read "Brake Job" or "Fixed Transmission" (what the h*** does that mean?) Needless to say, they went back for a more detailed accounting. After looking at log books I've seen some on aircraft that weren't much more complete and you have a hard time figuring out exactly what was done.

MikeB

[Paul Agaliotis]

Mike,
The work orders will have all of the work performed and parts and processes used. But the Repair Station is only required to keep them 3 years, I believe. I'm just too lazy to go look. So if the yellow tag is over 3 years old you have no record of repair other than the attached tag.
Paul

[MikeB]

Paul,
Understood. You often see log book entries such as: #4 cylinder rebuilt by XYZ company,. See work order '123' and of course, that work order doesn't exist any more. The engine on my 150 horse Cherokee was overhauled about 100 hours before I bought it. Ran fine but the log book entry was pretty vague. I even questioned the installation of 1/2 inch valves and guides until we pulled the covers. When the oil pump AD came up several years later there were some questions (it did have to be replaced). Anyway, never could come up with a work order that listed parts, etc. I've always been accused of being too 'wordy' anyway but it's hard to explain to a customer what repairs were done without proper documentation.

Right now I'm stuck in San Antonio for a month. May try to visit the ECI factory later. Warm anyway, it was 8 degree in Wisconsin this morning.

MikeB

[BugSmasher]

It does seem strange to me that there aren't bushings in the block. At least these could have been redesigned as inserts for the cases that are worn out. As an engineer, I don't understand why this wasn't done and why it couldn't be done. There are a lot of old engines out there that could benefit from a retrofit like this, were there one available.

[joea]

Am sure that had anyone told the engineers way back in the 1930's when this engine was first developed that it would be still up in the air and flying 80 years later, that they would be the laughing stock of their department!

Remember that engines during WW2 were usually given 25 hours on a airframe then swapped off for a new one. They were really "rode hard and put away wet" and as this was wartime, slap a new one on and keep fighting the next day.

Now, why someone has not come up with a STC to mill the cam areas out and put a bearing in it so that old crankcases could be used is a good question, but until we are running low on the 65 and 85 hp versions of the crankcases my guess is that this will not happen.

[jc pacquin]

What about the engine case? How old is it? Original? I can't think about the stress they have undergone! Say a 65 or 85! Are they safe? In "those days" almost every airport had one or more people that could recover an aeronca, cub, t-craft, cheaply,fast, and often. Dope and fabric, usually linen were plentiful. I look at a modern Husky for instance , with a glass panel, etc for 189,00.00! No wonder the country is in trouble! JC