No oil pressure?

[Quadruplecccc]

Just got finnished re-installing motor--(1976 233hp merc 351w) started right up, idles nice but now oil press. gauge reads zero. It worked before the pull out. How do I trbl shoot the sending unit or the guage. No knocks that I can hear so I'm sure oil pump is workin. Please help!

 

[Quadruplecccc]

Re: No oil pressure?

i put a volt meter to oil pressure sender and to ground but got no voltage. should it read 12 volts at sender?

 

[Eric 3.7LX Alpha 1]

Re: No oil pressure?

no doesn't work with voltage to the sender. It is grounded to the block. I believe It works with resistance to ground.

Put the key on and ground the wire to the sender and see if the gauge pegs.

 

[Quadruplecccc]

Re: No oil pressure?

should take the wire off the sender then ground it?

 

[Eric 3.7LX Alpha 1]

Re: No oil pressure?

correct.. while the key is in the run position, see if the gauge pegs.

 

[Quadruplecccc]

Re: No oil pressure?

It does nothing

 

[dirtdog38]

Re: No oil pressure?

go buy a cheap manal gage and find a oil hole to put it in thers many so leave the one u got ther then u will know what u got any way then start at the sending unit they crack easy on a install did u rebuild the motor. fords r good for little oil presure at low rpm

 

[Eric 3.7LX Alpha 1]

Re: No oil pressure?

Time to move under the dash:

Test procedure from the manual for the guage reads:

With the ignition off. Remove the "S" terminal wire off the back of the pressure gauge.

Turn on the ignition switch, the gauge should read the lowest setting on the gauge.

Turn the ignition switch off, Connect a jumper from "G" to "S" (G= ground S=sender)

Turn the ignition switch to on, Gauge must read full/high on the scale. if not replace the gauge. This is assuming that the (I or + terminal=ignition and the "G" terminal= ground both are getting what they are suppose to.

You can use a test light or multi meter to test the terminals and ensure they are good at I and G