Oil Pressure

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I'm surprised your mechanic didn't recommend replacing the oil pressure gauge with the engine overhaul. Seems to me you wouldn't want to be firing up a brand new engine for the first time with a gauge you think is likely to be faulty. But that's just me. I'm not an A&P.
Wouldn't you need some indication the gauge was faulty prior to spending the customer's money?
 
I once had an oil pressure gauge fail on me....bout 1 hr into a new engine run. Circled and landed ASAP....shut down...collected my thoughts....and took it back to Landmark. o_O


I demanded a new engine....but alls I got was a rebuilt gauge. :confused:
 
No pressure from 2 engines is some indication :)
I was not hired to trouble shoot, I was here to change an engine, I simply never saw the old engine run.
when I got here the mags were freshly overhauled awaiting installation on the new engine. So the old engine was not able to be run.
The first time I saw the gauge was inop, was first run of the new engine.
So don't imply I should have known.
 
I just wonder how many of you who seem to look for anything at all to rag Tom about, have ever met him?

I thought that I explained the situation pretty well. There were multiple reasons for replacing the engine. I bought an engine from Tom and he came to Texas to hang it and to see his daughter while he was here. I pulled the mags and sent them off so they would be ready for him when he got here, so he was unable to run the old engine himself, but even if he had, he would have seen low oil pressure among many other maladies, and been talking to an owner who was ready to replace it for many good reasons. He did not decide to replace the engine. I made the decision and made it clear earlier in the thread the multiple reasons for that decision. So since I said I was ready to replace it, why would he bother to check the gauge first? When we started the engine and pressure was within limits, but not as high as expected, he put a known good gauge on it right away. We found out what was up and kept moving forward.

I have worked in the hangar with Tom for several days, helping wherever I could. Working with someone several days gives you the opportunity to get to know them personally, see how much skill and knowledge they have as well as learn what they are about. I also took him through the war bird museum, another opportunity to see his MASSIVE aircraft knowledge. He also is generous to those in need. I won’t go into it, but he did a significant part helping someone in need while he was here. He is not a permanent member of our airport community, but he pitched in with the rest of us as if he were. The guys at the airport have been duly impressed with him.

Tom is honest, hardworking and pleasant to be around. I think he started this thread just to have fun with it. At any rate I really just don’t understand why people rag on him here. He is a good resource and a great asset to any community. He is someone who is honest, fair dealing and I like to think I can call he and his lovely wife Barb our new friends.

Oh, and by the way, my little Cessna now has a solid, sweet running engine.
 
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I was not hired to trouble shoot, I was here to change an engine, I simply never saw the old engine run.
when I got here the mags were freshly overhauled awaiting installation on the new engine. So the old engine was not able to be run.
The first time I saw the gauge was inop, was first run of the new engine.
So don't imply I should have known.
First engine had no pressure as per the customer. When someone tells me they observe no pressure, I don't immediately second-guess them. Second engine showed no pressure either. A couple of clues right there.
 
First engine had no pressure as per the customer. When someone tells me they observe no pressure, I don't immediately second-guess them. Second engine showed no pressure either. A couple of clues right there.
And that is when we put a direct reading gauge on it.
The first time I had reason to doubt the gauge.
 
First engine had no pressure as per the customer. When someone tells me they observe no pressure, I don't immediately second-guess them.
How would prove the gauge on an engine that would not run?
My first opportunity was with the new engine.
So forget the 2 engine theory.
I took my customers word that it was low pressure on a very old engine.
 
And that is when we put a direct reading gauge on it.
The first time I had reason to doubt the gauge.
Wasn't the first one direct reading too? They are generally Bourdon gauges, aren't they?
 
No pressure from 2 engines is some indication :)
Yeah, one is very old, the other is brand new.
I'll bet you are clariboyexnt and can just look at any engine and know the oil pressure running or not.
 
How would prove the gauge on an engine that would not run?
My first opportunity was with the new engine.
So forget the 2 engine theory.
It doesn't prove the gauge, by itself.
Quite frankly, while there are symptoms that would rule out the gauge, I'd be landing the plane before they would manifest themselves and so wouldn't be seen by the pilot (hopefully). Letting it go that long is a good way to make an emergency.
 
Yeah, one is very old, the other is brand new.
I'll bet you are clariboyexnt and can just look at any engine and know the oil pressure running or not.
Why should engine age make a difference? And new engines could fail, too.
 
Wasn't the first one direct reading too? They are generally Bourdon gauges, aren't they?
Presumably, I don't take them apart to see.
The direct reading gauge is a known good gauge, hooked up by its self does not depend upon the same lines as the installed one.
 
It doesn't prove the gauge, by itself.
Quite frankly, while there are symptoms that would rule out the gauge,
We had no symptoms, the aircraft was not flying or able to be run.
The first time we could put pressure on the gauge was with the new engine
 
Presumably, I don't take them apart to see.
The direct reading gauge is a known good gauge, hooked up by its self does not depend upon the same lines as the installed one.
What do you mean by direct reading? The first one was also direct reading, in that it read the pressure directly through mechanical flexing of a tube, wasn't it?
 
We had no symptoms, the aircraft was not flying or able to be run.
The first time we could put pressure on the gauge was with the new engine
It wouldn't be the first thing I would do, but a little pressure into the gauge would show nicely, even without an engine. Small air pump. So you could, in theory, put pressure on the gauge.
 
First engine had no pressure as per the customer. When someone tells me they observe no pressure, I don't immediately second-guess them. Second engine showed no pressure either. A couple of clues right there.

Ya’ THINK! First of all, your characterization of “no pressure” is incorrect. It showed low pressure, but within Continental limits, barely.
 
I'm beginning to believe you don't understand basic A&P
I asked a very simple question- how do you define direct reading? Your lack of communication skills are one cause of these "discussions". To my eyes, the original gauge was direct reading.

Do you understand wear?
What wears in an engine to make the gauge inoperative?
 
I asked a very simple question- how do you define direct reading? Your lack of communication skills are one cause of these "discussions". To my eyes, the original gauge was direct reading.


What wears in an engine to make the gauge inoperative?
This statement says you don't understand what pressure is.
Pressure is a resistance to flow, no resistance, no pressure.
old worn engines have no resistance
 
It doesn't prove the gauge, by itself.
Quite frankly, while there are symptoms that would rule out the gauge, I'd be landing the plane before they would manifest themselves and so wouldn't be seen by the pilot (hopefully). Letting it go that long is a good way to make an emergency.

Good grief man! I have monitored this engine more closely than a lot of pilots I know. I flew the thing all over the place, recognized problems before emergencies and kept it in the air. I haven’t flown it at night since before it hit TBO. I replaced the engine to have a better chance of NOT dealing with an emergency. Geesh!
 
I just wonder how many of you who seem to look for anything at all to rag Tom about, have ever met him?

I thought that I explained the situation pretty well. There were multiple reasons for replacing the engine. I bought an engine from Tom and he came to Texas to hang it and to see his daughter while he was here. I pulled the mags and sent them off so they would be ready for him when he got here, so he was unable to run the old engine himself, but even if he had, he would have seen low oil pressure among many other maladies, and been talking to an owner who was ready to replace it for many good reasons. He did not decide to replace the engine. I made the decision and made it clear earlier in the thread the multiple reasons for that decision. So since I said I was ready to replace it, why would he bother to check the gauge first? When we started the engine and pressure was within limits, but not as high as expected, he put a known good gauge on it right away. We found out what was up and kept moving forward.

I have worked in the hangar with Tom for several days, helping wherever I could. Working with someone several days gives you the opportunity to get to know them personally, see how much skill and knowledge they have as well as learn what they are about. I also took him through the war bird museum, another opportunity to see his MASSIVE aircraft knowledge. He also is generous to those in need. I won’t go into it, but he did a significant part helping someone in need while he was here. He is not a permanent member of our airport community, but he pitched in with the rest of us as if he were. The guys at the airport have been duly impressed with him.

Tom is honest, hardworking and pleasant to be around. I think he started this thread just to have fun with it. At any rate I really just don’t understand why people rag on him here. He is a good resource and a great asset to any community. He is someone who is honest, fair dealing and I like to think I can call he and his lovely wife Barb our new friends.

Oh, and by the way, my little Cessna now has a solid, sweet running engine.

You don’t see how the misrepresented facts in the OP could turn people off?
 
Ya’ THINK! First of all, your characterization of “no pressure” is incorrect. It showed low pressure, but within Continental limits, barely.
Tom didn't bother to mention that, nor suggest otherwise in his replies.

Have you ever seen a rebuilt engine fail to produce oil pressure?
My experiences are an extremely small sample, and are not representative of the population of rebuilt engines. I probably flew with maybe 2 rebuilt or new engines.
 
This statement says you don't understand what pressure is.
Pressure is a resistance to flow, no resistance, no pressure.
old worn engines have no resistance

No Tom, many people, even those who work on engines, don’t really understand oil pressure. I have seen people many times try to cure low oil pressure with an oil pump or shimming the relief valve as if it were a magic adjustment for a worn out engine. They have no clue that in almost all cases when the pressure goes down it means that the bearings and/or crankshaft have worn to excessive clearance which lets oil flow more freely rather than making resistance to flow that creates pressure.
 
Good grief man! I have monitored this engine more closely than a lot of pilots I know. I flew the thing all over the place, recognized problems before emergencies and kept it in the air. I haven’t flown it at night since before it hit TBO. I replaced the engine to have a better chance of NOT dealing with an emergency. Geesh!
You've done a great job of being safe and getting as much time as possible from your engine.
You simply became aware that you didn't trust the engine.
 
Was that so hard now?

You obviously don’t know how the gauge is installed. The gauge in the panel is a direct reading too. Tom just disconnected it and connected the known gauge to the same line which leads directly to the engine near the relief valve. IOW, the panel gauge IS a directly connected gauge.
 
This statement says you don't understand what pressure is.
Pressure is a resistance to flow, no resistance, no pressure.
old worn engines have no resistance
No, pressure is the force applied perpendicular to the surface on an object over an area where that force is distributed.
Hence the units PSI (pounds per square inch), newton per square meter, and so forth. I'm sitting in a room with no wind (flow), but the air pressure is 14.7 PSI.
What resistance does a new engine have?
 
You've done a great job of being safe and getting as much time as possible from your engine.
You simply became aware that you didn't trust the engine.

Thank you! Yes I became aware when it was untrustworthy at the point at which it became untrustworthy.
 
You obviously don’t know how the gauge is installed. The gauge in the panel is a direct reading too. Tom just disconnected it and connected the known gauge to the same line which leads directly to the engine near the relief valve. IOW, the panel gauge IS a directly connected gauge.
Isn't that what I said?
See below:
Wasn't the first one direct reading too? They are generally Bourdon gauges, aren't they?
 
No, pressure is the force applied perpendicular to the surface on an object over an area where that force is distributed.
Hence the units PSI (pounds per square inch), newton per square meter, and so forth. I'm sitting in a room with no wind (flow), but the air pressure is 14.7 PSI.
What resistance does a new engine have?

Your question is not applicable. We are talking about OIL PRESSURE. As the bearings wear, the space between them opens, requiring less pressure to force oil through. Tee a guage on a water faucet and connect a hose with a variable opening valve on the other end. Watch the pressure as you gradually open the valve. As the flow increases the pressure will decrease. It’s not rocket science. If you were paying attention, you learned this in eight grade science class.
 
Your question is not applicable. We are talking about OIL PRESSURE. As the bearings wear, the space between them opens, requiring less pressure to force oil through. Tee a guage on a water faucet and connect a hose with a variable opening valve on the other end. Watch the pressure as you gradually open the valve. As the flow increases the pressure will decrease. It’s not rocket science. If you were paying attention, you learned this in eight grade science class.
It certainly is applicable. You and Tom seem to be defining pressure differently from the rest of the world. Pressure is a force applied perpendicular to a surface over an area. It doesn't matter what the source of the pressure may be. When you lean on a wall, you apply pressure.

Do you finally understand it?
Actually, no because your customer said the same thing I did and you didn't correct him. He said his original gauge was direct reading, too.
 
You don’t see how the misrepresented facts in the OP could turn people off?

He simply indicated low oil pressure when he wrote “no” oil pressure. Lots of people talk like this. They might say that their car is “out of gas” when it is actually low on gas.
 
Good grief!
It certainly is applicable. You and Tom seem to be defining pressure differently from the rest of the world. Pressure is a force applied perpendicular to a surface over an area. It doesn't matter what the source of the pressure may be. When you lean on a wall, you apply pressure.

You’ve never taken a fluids class have you?

In the case of a fluid the pressure is applied perpendicular to all surfaces that contain it. Is there a college near you? It’s never to late to learn about such things.

I think Tom meant he connected it to the same line except in the engine compartment. In effect they are connected directly to the same point directly on the engine.
 
Good grief!


You’ve never taken a fluids class have you?

In the case of a fluid the pressure is applied perpendicular to all surfaces that contain it. Is there a college near you? It’s never to late to learn about such things?
Yes, that's exactly right. Air is a fluid too, and applies pressure all around us. What am I saying that is incorrect? You are merely restating what I said.
 
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