---------------------------------------------------------- Rocket-List Digest Archive --- Total Messages Posted Fri 06/16/06: 3 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 01:07 AM - UMA 1 1/4" instruments (Phil Ayrton) 2. 06:47 AM - () 3. 07:53 AM - Re: UMA 1 1/4" instruments (Ron Carter) ________________________________ Message 1 _____________________________________ Time: 01:07:11 AM PST US From: "Phil Ayrton" Subject: Rocket-List: UMA 1 1/4" instruments I have just completed an RV-4 180hp project, and have used some of the small UMA 1 1/4" instruments (oil pressure, oil temperature and fuel pressure) to help save space on the small RV-4 panel. They look great, but I have a problem with them during flight. I am getting wildly erratic readings while flying. My oil pressure gauge sometimes reads 80-90psi, then will drop to zero, and often sits at zero while flying after showing a sensible reading at start up and run up, and it often flickers inflight. The low pressure light has not come on and the engine has always remained operational, also my oil temp gauge initially appears to operate as expected then runs up to the 300 deg F peg, then back to 250, back to 300 for a minute or more. After aborting these flights and returning to base under partial power the engine shows no sign of damage or overheating. I have just ordered a new oil temp probe and oil pressure sensor from Aircraft Spruce to take away any suspicion of incorrect sensors, but I think I may have an electrical/wiring problem. There was no wiring diagram in the box when these arrived from Spruce and so far my email to UMA remains unanswered. I notice some of the Rocket photos show these gauges. Can anyone provide information on these gauges, their reliability and performance during flight. Any other suggestions regarding wiring checks would also be greatly appreciated. Philip Ayrton Australia ________________________________ Message 2 _____________________________________ Time: 06:47:43 AM PST US From: Subject: Rocket-List: --> Rocket-List message posted by: Your engine gauges HAVE to be grounded to the engine itself. Not the instrument panel or anywhere inside the plane. It can change the readings drastically. Might be the cause. do not archive ________________________________ Message 3 _____________________________________ Time: 07:53:31 AM PST US From: "Ron Carter" Subject: Re: Rocket-List: UMA 1 1/4" instruments I have a UMA fuel pressure gauge. It bounces quite a bit,+ - 12 psi sometimes. Then other times it is totally stable. I have tried three of them over the years with pretty much the same result for all of them. Ron Carter, HR2 ----- Original Message ----- From: Phil Ayrton To: rocket-list@matronics.com Sent: Friday, June 16, 2006 2:03 AM Subject: Rocket-List: UMA 1 1/4" instruments I have just completed an RV-4 180hp project, and have used some of the small UMA 1 1/4" instruments (oil pressure, oil temperature and fuel pressure) to help save space on the small RV-4 panel. They look great, but I have a problem with them during flight. I am getting wildly erratic readings while flying. My oil pressure gauge sometimes reads 80-90psi, then will drop to zero, and often sits at zero while flying after showing a sensible reading at start up and run up, and it often flickers inflight. The low pressure light has not come on and the engine has always remained operational, also my oil temp gauge initially appears to operate as expected then runs up to the 300 deg F peg, then back to 250, back to 300 for a minute or more. After aborting these flights and returning to base under partial power the engine shows no sign of damage or overheating. I have just ordered a new oil temp probe and oil pressure sensor from Aircraft Spruce to take away any suspicion of incorrect sensors, but I think I may have an electrical/wiring problem. There was no wiring diagram in the box when these arrived from Spruce and so far my email to UMA remains unanswered. I notice some of the Rocket photos show these gauges. Can anyone provide information on these gauges, their reliability and performance during flight. Any other suggestions regarding wiring checks would also be greatly appreciated. Philip Ayrton Australia