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MrPandy
07-08-2006, 07:58 PM
I'm finally installing my previously missing oil pressure gauge, but something has me confused. The PO blocked the connector in the engine block with a screw so the oil would not leak out. I got a new connector, a gauge, and the tube to connect them together (actually, a braided hose). Where does the air that is presently in the hose go? How can the oil get to the gauge if the line is full of air? /ubbthreads/images/graemlins/confused.gif

jerrybny
07-08-2006, 08:28 PM
With pressure up, you could loosen the connection at the gauge until the air is bled out. Be sure to wrap a rag around it as I'm sure the oil is gonna come out of the tube with some remarkable velocity. Or you could disconnect the tube and put it a small container and then start the engine. Once oil is coming out shut the engine off and connect the tube back up. 1 other idea is to loosen the pipe at the engine end to let the air bleed out and oil reach the gauge as the engine is running. I'm not sure the last one will work though. Good luck /ubbthreads/images/graemlins/cheers.gif

07-08-2006, 08:53 PM
You could try sucking it out, but that would taste pretty bad.
(That's a joke. Please don't try this at home.)


Bill

Dave Russell
07-08-2006, 08:58 PM
[ QUOTE ]
Where does the air that is presently in the hose go? How can the oil get to the gauge if the line is full of air? /ubbthreads/images/graemlins/confused.gif

[/ QUOTE ]
In the line, pressure is pressure. 20 psi of air pressure is the same as 20 psi of oil pressure. The gage doesn't care which it reads. Actually, the air is a bit compressible & may help damp rapid gage vibration.
D

vettedog72
07-09-2006, 07:28 AM
Good question and I don't have an answer. BUT, come to think of it, that plastic line has never been replaced on my '74 TR6; is it time? Are there known failure rates on that oil line?

martx-5
07-09-2006, 09:46 AM
[ QUOTE ]
[ QUOTE ]
Where does the air that is presently in the hose go? How can the oil get to the gauge if the line is full of air? /ubbthreads/images/graemlins/confused.gif

[/ QUOTE ]
In the line, pressure is pressure. 20 psi of air pressure is the same as 20 psi of oil pressure. The gage doesn't care which it reads. Actually, the air is a bit compressible & may help damp rapid gage vibration.
D

[/ QUOTE ]

I had to replace the line in my TR3 years ago (before I started the resto), and never bled it out. It worked fine right from start-up. I doubt they bled them out at the factory when first installed, they had enough other oil leaks to worry about. /ubbthreads/images/graemlins/lol.gif /ubbthreads/images/graemlins/hammer.gif