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wacky oil pressure gauge

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08-25-2008, 03:08 PM
beeoh
wacky oil pressure gauge
just fired up the Barth on the weekend to find the oil pressure gauge pegged to the high side of pressure reading...shut off engine and then turned key back on to find gauge needle pegging again...am I looking at a faulty gauge? It is an electric gauge with sending sensor. thanks for any ideas on the fix...


Bob and Jan Orr
Canadian Barth owners
94 30ft. Breakaway/3116 Cat/ Allison 5 speed/ Gillig
08-25-2008, 03:17 PM
Bill N.Y.
A pegged gauge usually means a shorted sending unit or the wire to the sending unit is grounding out to a ground source.

Pull off the wire(s) to the sending unit. If it goes back to 0 with the key on and wire(s) off, you probably have a defective sending unit.


˙ʎ˙u ןןıq- „ǝןƃuɐ ʇuǝɹǝɟɟıp ɐ ɯoɹɟ pןɹoʍ ǝɥʇ ʇɐ ʞooן ɐ ƃuıʞɐʇ sı ǝɟıן oʇ ʇǝɹɔǝs ǝɥʇ„

Regis Widebody1990 Barth Regis Widebody
8908 0128 40RDS-C1
L-10 Cummins
Allison MT647 Transmission
Spartan Chassis
Regal Conversion1991 Medical Lab Conversion
9102 3709 33S-12
Ford 460 MPFI
C6 Transmission
Oshkosh Chassis



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08-25-2008, 03:39 PM
Danny Z
Bill, does this hold true with a 454 gasser? My gauge pegged last trip and I haven't gotten around to investigating the cause yet. D'oh


79 Barth Classic
08-25-2008, 04:20 PM
Bill N.Y.
quote:
Originally posted by Danny Z:
Bill, does this hold true with a 454 gasser?
It should on most sending unit. Oil, temp, fuel level, etc...


˙ʎ˙u ןןıq- „ǝןƃuɐ ʇuǝɹǝɟɟıp ɐ ɯoɹɟ pןɹoʍ ǝɥʇ ʇɐ ʞooן ɐ ƃuıʞɐʇ sı ǝɟıן oʇ ʇǝɹɔǝs ǝɥʇ„

Regis Widebody1990 Barth Regis Widebody
8908 0128 40RDS-C1
L-10 Cummins
Allison MT647 Transmission
Spartan Chassis
Regal Conversion1991 Medical Lab Conversion
9102 3709 33S-12
Ford 460 MPFI
C6 Transmission
Oshkosh Chassis



Quick Link: Members Only Link To Send Me A Private Message
08-26-2008, 11:09 AM
billyt53
The oil pressure sender is a variable device that tends to do that after many years of moving back and forth. I tell my customers if you turn the key on, engine off and it reads zero, then only moves after you start it then you are fine until you can change the sender. Typically at idle it will read a reasonable pressure, but as you increase throttle, it pegs out. An ohm meter on the pressure switch terminal will confirm that behavior. Ford had so much trouble with this that they went away from it all together and made the oil pressure gauge essentialy and idiot light with a needle. They used a switch that closed at about 12 psi and whether the engine had 20 or 120 psi oil pressure, the needle was "Normal"
Billy T


Billy & Helen Thibodeaux

Retired from Billy Thibodeaux's Premiere RV, Inc. Scott, LA 70583 I-10 Exit 97
The Farm is near Duson, LA I-10 Exit 92 then N 1 mile on right
Three Full 50 Amp RV Hookups !
billynhelen@me.com
Data Tag: 9404-3908-36XI-2C
1994 Sovereign 36' Widebody on Spartan IC (Mountain Master Lite) Chassis.
Powered by Cummins ISL9-450
Onan 8,000 Quiet Diesel Genset
Toad: 2018 Chevy Colorado ZR2 Diesel with M&G Car Brake
08-26-2008, 07:05 PM
BarthBluesmobile
Even after taking the stock P30 instrument out of the Bluesmobile, the oil pressure gauge still read out 60 PSI. I figure GM engineers these things for a certain number of years and miles of use. That was probably not in anticipation of sitting idle for 2 decades either. [look at the bright side, you have evidence to show your wife that you *NEED* VDO or Autometer gauges.... Cool]
Matt


1987 Barth 27' P32 Chassis
Former State Police Command Post
Chevrolet 454
Weiand Manifold, Crane Cam, Gibson Exhaust
09-10-2008, 11:24 PM
beeoh
problem was in the sending unit...looking on line for best buy..its a VDO 0-150psi.


Bob and Jan Orr
Canadian Barth owners
94 30ft. Breakaway/3116 Cat/ Allison 5 speed/ Gillig
09-13-2008, 08:17 PM
billyt53
Call Instrument Sales and Service in Kent, WA (800) 333-7976. They have everything related to instruments.


Billy & Helen Thibodeaux

Retired from Billy Thibodeaux's Premiere RV, Inc. Scott, LA 70583 I-10 Exit 97
The Farm is near Duson, LA I-10 Exit 92 then N 1 mile on right
Three Full 50 Amp RV Hookups !
billynhelen@me.com
Data Tag: 9404-3908-36XI-2C
1994 Sovereign 36' Widebody on Spartan IC (Mountain Master Lite) Chassis.
Powered by Cummins ISL9-450
Onan 8,000 Quiet Diesel Genset
Toad: 2018 Chevy Colorado ZR2 Diesel with M&G Car Brake
09-20-2008, 10:02 AM
Danny Z
Where is the oil pressure sending unit on a 454 Cheby?


79 Barth Classic
09-20-2008, 10:10 AM
bill h
quote:
Originally posted by Danny Z:
Where is the oil pressure sending unit on a 454 Cheby?


Left side of the block, low, forward of the motor mount. If not there, look farther back, above the oil filter.


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