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  #1  
Old 08-15-2018, 11:37 AM
burgessbuilderMO13 burgessbuilderMO13 is offline
 
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Location: Perth ont
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Default Manifold pressure problem

Running a Van's manifold pressure gauge system on a 7A , O-360 A1A. It has worked fine for years and close to 500 hours. Now it indicates atmospheric on the ground, but never drops below 25" when running.
The needle does move, but certainly not as it should.
Has anyone had a similar issue. I'm thinking the transmitter is toast.
Thanks
Dale
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  #2  
Old 08-15-2018, 11:51 AM
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longranger longranger is offline
 
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Could be a leaky hose between the port and the sender.
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  #3  
Old 08-15-2018, 11:56 AM
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Sounds like a leak.
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  #4  
Old 08-15-2018, 12:15 PM
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N941WR N941WR is offline
 
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If it is not a leak, you might want to change MAP sensor. We have had a number of them good bad. If you do not find a leak and want to change it, order the replacement from your EFIS manufacture.

Some of the cheaper sensors our customers have bought from their local auto parts supplier.
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  #5  
Old 08-15-2018, 01:20 PM
burgessbuilderMO13 burgessbuilderMO13 is offline
 
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Location: Perth ont
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Default Man pressure

Notice in the OP that we are using the vans gauge, no Efis.
Lines have been checks, no leaks

Dale
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  #6  
Old 08-16-2018, 08:19 AM
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longranger longranger is offline
 
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Just a thought: Did you check the line with pressure or vacuum? In my career in instrumentation I saw plenty of instances when a line would hold pressure but wouldn’t hold a vacuum.
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RV-7 TU 904KM (reserved)
Wings Fitted and Finish Kit on order

Construction Log
Picasa: Empennage Album, Wings Album, Fuselage Album

1955 Cessna 170B flying since 1982

'To get something you never had, you have to do something you never did.' -Unk.
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