After not getting any good feedback I tried it and posted about the results HERE. Read on for original posting.
Should I just bend my oil pressure bimetal mechanism to get it into a reasonable range?
If so where should I bend it?
Also WTF is inside the oil pressure sender?
I've been through 10 of the 50 pages returned by site search and used google to search the site to no avail.
In way of explanation:
My mechanic attached my oil pressure lead to the ground pin. Probably knocked it off while changing the fuel pump.
I drove it and noticed that it was pegged.
I moved the lead to the center and now it barely moves.
The oil pressure is good. The sender is practically new.
I checked the gauge resistance and it is 45 ohms service manual says it should be 55 ohms.
If I check it in series with a 3 watt bulb as described in the service manual it barely moves.
If I put 12.5v (starting battery) across it and moves nicely and draws 250mA which calculates out to about 50 ohms (bad ohm meter maybe?)
I'm assuming the gauge is a bimetal actuator that is heated by a resistance wire and that the "sender" modulates the current and thus the heating of the bimetal actuator.
I also assume that the resistance wire failure mode is open circuit.
Since the wire clearly heats the bimetal actuator the heating wire has full nominal function, given the previous statement.
Therefore the electrical fundamentals of the gauge are intact but perhaps the mechanical part is out of calibration.
The only way to "adjust" the mechanical part is to bend the bimetal part as far as I can tell.
I have also checked the sener per the manual.
With the engine off no continuity through the sender.
With the engine running the light goes full on for a few seconds then gets dimmer and starts to fluctuate.
If I put a current meter on it the current fluctuates after a few seconds
I can not really see a difference between high and low RPM.
WTF is going on inside the sender? I had assumed it would be some sort of variable resistor but clear from what the manual say to do for diagnostic and what I measured it isn't just a rheostat. I find the few seconds of current before it start fluctuation to be particularly perplexing.
Should I just bend my oil pressure bimetal mechanism to get it into a reasonable range?
If so where should I bend it?
Also WTF is inside the oil pressure sender?
I've been through 10 of the 50 pages returned by site search and used google to search the site to no avail.
In way of explanation:
My mechanic attached my oil pressure lead to the ground pin. Probably knocked it off while changing the fuel pump.
I drove it and noticed that it was pegged.
I moved the lead to the center and now it barely moves.
The oil pressure is good. The sender is practically new.
I checked the gauge resistance and it is 45 ohms service manual says it should be 55 ohms.
If I check it in series with a 3 watt bulb as described in the service manual it barely moves.
If I put 12.5v (starting battery) across it and moves nicely and draws 250mA which calculates out to about 50 ohms (bad ohm meter maybe?)
I'm assuming the gauge is a bimetal actuator that is heated by a resistance wire and that the "sender" modulates the current and thus the heating of the bimetal actuator.
I also assume that the resistance wire failure mode is open circuit.
Since the wire clearly heats the bimetal actuator the heating wire has full nominal function, given the previous statement.
Therefore the electrical fundamentals of the gauge are intact but perhaps the mechanical part is out of calibration.
The only way to "adjust" the mechanical part is to bend the bimetal part as far as I can tell.
I have also checked the sener per the manual.
With the engine off no continuity through the sender.
With the engine running the light goes full on for a few seconds then gets dimmer and starts to fluctuate.
If I put a current meter on it the current fluctuates after a few seconds
I can not really see a difference between high and low RPM.
WTF is going on inside the sender? I had assumed it would be some sort of variable resistor but clear from what the manual say to do for diagnostic and what I measured it isn't just a rheostat. I find the few seconds of current before it start fluctuation to be particularly perplexing.
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