Oil Pressure Gauge Needle Sways Back n Forth

[APOCALYPSEof87]

Hey guys, like the title says, my needle on my oil pressure gauge sways back an forth between low and high normal. This will happen when i slow down or speed up/ at rest at the stoplight.

This happened after i changed the oil with 10w-30 Castrol oil, and exactly next week i flushed out the convential 10w-30 Castrol oil with an quart of oil flush solution and put in Synthetic Royal Purple 5w-30 oil.

I've been looking at other comments from other threads. Most of them suggest that the stock electrical oil pressure gauge is to blame and to get an aftermarket mechanical gauge.

I purchased a new "Oil switch with gauge" from pepboys, Part #S4048. Im about to install it and test it out today to see if that will fix the problem, if not. Then it up to your guys' answers.

My dad let me borrow a Mechanical oil pressure gaugefrom his '57 Chevy Bel Air. But i do not have the connectors to change the electrical sensor to mechanical.

My questions are....

1) Is the change from conventional to synthetic oil a factor of the needle movement?

2) Although the stock oil pressure gauge works, does that necessarily mean that the bearings are bad as well?

3) I've heard that using a quart of oil flush is harmful to your engine. Is this fact or myth? and how and why is this true or not?

4) Does anyone know if i need to purchase the parts to convert the electrial oil pressure sensor to mechanical? And if so, where?




I appreciate any and all help. Thank you to those who take time to answer the questions of those who dont have answers.

Thank you again.
Gabriel

 

[The Shape]

I think any performance engine that see's hard driving should have a mechanical full sweep oil PSI gauge. It is the only way to really know whats going on with your engine.

 

[jrichker]

Mechanical oil pressure gauge installation.


1.) Remove old pressure sender. It is located down by the oil filter and has 1 wire on a push on screw connector.
2.) Install ¼” pipe tee fitting with a short ¼” nipple on the place where you removed the oil pressure sender.
3.) Install the original oil pressure sender back in one of the tee ports.
4.) Install the gauge line restrictor in the remaining port of the tee.
5.) Connect the flex tubing or hydraulic hose to the gauge restrictor. Be sure to route the tubing or hose away from the exhaust manifolds. Be sure to either use hydraulic hose or oil and heat resistant flex tubing for the pressure line. Do not use copper tubing for the connection to the gauge restrictor or engine. Over a period of time, the vibration will work harden the tubing and cause it to crack and fail.
6.) If the gauge is going to mount under the hood, connect it to the end of the hose or flex tubing. Use some Tie-wraps to secure the gauge and its plumbing to the wiring harness on the driver’s side inner fender.
7.) If the gauge is going to mount in the passenger compartment you get to find a place to run the tubing through the firewall. I suggest that you pick your spot from the inside since that is the area with the most difficult access. Do not run the tubing through the exact same hole as the steering shaft. It will tangle up with the steering shaft and cause major problems.
8.) Install the gauge inside the car in the location of your choosing. Connect the pressure line to the gauge and secure it out of the way of moving parts with Tie-wraps.
9.) Be sure to ground the gauge lighting wire to clean, shiny bare metal. Connect the other wire from the gauge lighting to a light brown/red wire on the radio wiring harness. There are 2 connectors in the radio wiring harness, but only one of them has the light brown/red wire you need for gauge illumination. Solder the gauge lighting wire to the light brown/red wire on the radio harness and cover the soldered joint with heat shrink.

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