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1st engine start-oil press. and fuel press ques.

J

jdiehl

Well Known Member
Today was my first engine start. I have a FSDO inspection scheduled in 10 days and need to hustle to get the project wrapped up. I have a new Lycoming 0-360-A1A (carb). To my surprise and pleasure, after a quick hit of electric fuel pump, it fired up immediately. All was well except the following:
1. The oil press stabilized at 45 psi in the yellow below the green range. Using a standard Vans series 2 1/4" oil pressure gauge and IE411K transducer.
2. Fuel press at 9 psi which is outside top end of green zone using standard vans series fuel press gauge and IE411AB transducer.

The A&P assisting me today believes that the transducers and/or gauges are in error. Any thoughts are much appreciated.
Jim Diehl N891DD
RV-7A
Lock Haven, Pa
 
Congrats!!!!!!!!!!!!

jdiehl said:
Today was my first engine start. I To my surprise and pleasure, after a quick hit of electric fuel pump, it fired up immediately.
Jim Diehl N891DD
RV-7A
Lock Haven, Pa
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Jim, welcome to another milestone on the road to a being a successful flying machine builder.
 
After verifying the accuracy of your pressure indication, turn up your oil pressure adjustment bolt a little - maybe a couple turns on the bolt, but higher power oil pressure reading is more important. As long as it doesn't exceed 90 psi or so when the oil is warm, you're OK. You may need to turn yours in a few turns. I had to back mine out about 8-10 turns because it was too high at takeoff power.
 
You did not mention what RPM the 45 psi occurred at. If it was idle with fully warm oil I would not worry about it. The minimum oil pressure at idle is 25 PSI. If it was at 2000 then you should be above 60 at that point.

George
 
OOPS, I forgot to mention that I ran it up to 1200 rpm for no more than about 30 seconds. Then ran it at idle to check rpm (showed about 600 rpm). Total engine run was less than about 3 minutes. I can understand the low oil pressure at a low rpm, but how about the high fuel pressure?

Jim
 
Like George said, if your at idle 45psi is a good start. As for the fuel pressure you didn't say if you were fuel injected or other. If carbuerated you are ok.
Ryan
 
jdiehl said:
carbureted. Also, I'm using Aeroshell 100 mineral oil if that helps.
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I have battled high fuel pressures in my carbureted airplane and have even replaced the fuel pump in an effort to solve this problem. I believe that my fuel pressure gauge is accurate and when the pressure gets up to around 7 PSI at idle on the ground the engine does not run well at all. I can make it run fairly well with extreme leaning when this problem is occurring, which is mostly during cold temperatures. If the engine runs fine at idle, I would think you don't have a true high pressure problem.
 
I think you are fine on the oil pressure. I know the idle limit is 25. I am not 100 percent on when the 60 PSI minimum starts but have been told you need 60 by 2000 RPM. Sounds like you will be just fine. The fuel pressure may be another issue. I don't know much about carbed engines but I am sure others will jump in.

George
 
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