SoCal Jet Boats

Tech Talk => Engine Mechanical / Electrical => Topic started by: joinerboy on March 20, 2014, 05:34:33 PM

Title: Oil pressure gauge
Post by: joinerboy on March 20, 2014, 05:34:33 PM
I have a gaffrig II oil pressure gauge. I used the sending unit that was already on the motor. (Stock gm) the gauge just pegs out to 80 when key is turned on. Do i need a gaffrig sending unit or is something wrong? Ive tried to figure out if i have a wire crossed but all wiring seems correct.


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Title: Re: Oil pressure gauge
Post by: beerjet on March 20, 2014, 05:41:13 PM
Sounds like you got really good oil pressure.

-beerjet-

Title: Re: Oil pressure gauge
Post by: tunnels on March 20, 2014, 05:52:52 PM
Unplug the wire at the sending unit. Is the gauge still pegged, gauge or wire problem. If not sending unit problem.
Title: Re: Oil pressure gauge
Post by: beerjet on March 20, 2014, 06:30:03 PM
I have a gaffrig II oil pressure gauge. I used the sending unit that was already on the motor. (Stock gm) the gauge just pegs out to 80 when key is turned on. Do i need a gaffrig sending unit or is something wrong? Ive tried to figure out if i have a wire crossed but all wiring seems correct.


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typically a ground wire issue...

-beerjet-

Title: Re: Oil pressure gauge
Post by: joinerboy on March 20, 2014, 06:47:58 PM
Unplug the wire at sending unit and the gauge goes to zero. Its a brand new auto zone sending unit.


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Title: Re: Oil pressure gauge
Post by: joinerboy on March 20, 2014, 08:08:30 PM
Ok after reading through numerous post i think i have a sender thats made for a "light". Bc it has a spade terminal on it. Am i correct with this??


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Title: Re: Oil pressure gauge
Post by: beerjet on March 20, 2014, 08:11:19 PM
Ok after reading through numerous post i think i have a sender thats made for a "light". Bc it has a spade terminal on it. Am i correct with this??


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Makes sense....
Only one way to find out.

-beerjet-

Title: Re: Oil pressure gauge
Post by: beerjet on March 20, 2014, 08:12:05 PM
Ok after reading through numerous post i think i have a sender thats made for a "light". Bc it has a spade terminal on it. Am i correct with this??


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Does it go back to zero after you start the motor?

-beerjet-

Title: Re: Oil pressure gauge
Post by: joinerboy on March 20, 2014, 08:18:19 PM
No it stays at 80


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Title: Re: Oil pressure gauge
Post by: Bradbury831 on June 04, 2018, 11:44:15 AM
I Know this is a old thread but im having the exact same issues so I figured I could save some questions. New gauge and new sender. ignition on but motor off gauge pegs at 80. Unplug sender wire with ing on and goes to 0. I have a 90* fitting with teflon tape on the sender connecting to the block and read I could interrupt the sender grounding?? Any help?
Title: Re: Oil pressure gauge
Post by: JordanDangerfield on June 04, 2018, 01:02:39 PM
I Know this is a old thread but im having the exact same issues so I figured I could save some questions. New gauge and new sender. ignition on but motor off gauge pegs at 80. Unplug sender wire with ing on and goes to 0. I have a 90* fitting with teflon tape on the sender connecting to the block and read I could interrupt the sender grounding?? Any help?

It’s more than likely the Teflon tape creating a bad ground.
Title: Re: Oil pressure gauge
Post by: Bradbury831 on June 05, 2018, 08:45:07 AM
I will pull it apart and remove the tape. Any other ideas or things I can try while having it apart?
Title: Re: Oil pressure gauge
Post by: JordanDangerfield on June 05, 2018, 02:49:51 PM
I will pull it apart and remove the tape. Any other ideas or things I can try while having it apart?

It could be the wrong sending unit for the gauge.
Title: Re: Oil pressure gauge
Post by: Bradbury831 on June 05, 2018, 03:19:49 PM
It could be the wrong sending unit for the gauge.

I made sure it was a sender and not a switch and also made sure the psi rating matched. Looked exactly the same as the one that came on the boat. Its only a single wire sender so I figured it would be easy to set up.
Title: Re: Oil pressure gauge
Post by: Bradbury831 on June 12, 2018, 08:27:10 AM
Took the sender and fittings apart last night. Cleaned all the tape of and wire brushed the port on the engine o make sure it would ground. Still pegged with key turned to on (Motor not running). Take the sending wire off the sender and goes to zero. Im going to get another sender and try that tonight. Any other ideas?
Title: Re: Oil pressure gauge
Post by: havasuman on June 15, 2018, 06:52:44 AM
Ground from gauge.
I am by no means a mechanic but tinkering over some time I learned to check ground from up front.


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Title: Re: Oil pressure gauge
Post by: Bradbury831 on July 03, 2018, 09:23:11 AM
Update. I got a new sender from stewart warner and now its working but its not reading correctly. My pressure test gauge is reading about 50 psi at idle while my dash gauge is reading 75-80 psi at idle. Made sure the new sender psi matched the gauge but I dont know what to do from here?? Any ideas?
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