Engine To replace the oil pump or not replace the oil pump, that is the question

I have low oil pressure on my 89 LX Sport ragtop, 5.0 5 speed. When I bought it from the original owner at 193,000 miles, he had only driven it about 100 miles a year for the previous 8 years. As I drove it the 3 miles to the house it showed no oil pressure. I pulled the sending unit and it was plugged solid. A quick trip to the parts store and 10 minutes later I had reasonable pressure for an engine with those miles. I wondered what else was plugged up. The car has had synthetic oil since new. When the car warms up the pressure is at about 1/4 of the gauge, at an idle probably about an eighth. It has had no major work on the engine itself, just peripherals, alternators, water pump, cap and wires, and AC compressor, oh, yeah and a new clutch and pressure plate at about 175,000. I replaced the valve cover gaskets when I first got it, and was absolutely amazed at how clean the valve train and the inside of the valve covers were. This is the first engine I have worked on that has only had synthetic oil in it, I am very impressed. I take it up to 5,00 rpm occasionally, and it still feels pretty together. So enough yak, as the oil pump is the original pump, it has to have some wear on it, I'm confident replacing it will raise the oil pressure some, or even just increase the flow, the engine has to have wear on it, my biggest concern is that if I increase the oil flow and or pressure I will then risk leaks at the oil seals, and valve seals. Has anyone out there replaced the oil pump on a high miles performance engine without any leakage?
 
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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 blue/red wire on the radio wiring harness. There are 2 connectors in the radio wiring harness, but only one of them has the light blue/red wire you need for gauge illumination. Solder the gauge lighting wire to the light blue/red wire on the radio harness and cover the soldered joint with heat shrink.

How to solder like a pro - [
View: http://youtu.be/uaYdCRjDr4A
a must view for any automotive wiring job.

Be sure to use a gauge restrictor fitting in the pressure line going to the gauge. The restrictor will prevent all of the engine's oil supply from ending up on the pavement before you can stop it if the gauge line fails. I had a gauge line rupture, and the restrictor fitting saved my engine from serious damage.

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Changing the oil pump on a 200,000 mile car isn't really sensible.
Rarely (if ever) does replacing a working oil pump have any effect.
They really either work or they don't.

And since you suggest the engine is clean and cared for, the junk that would ruin the oil pump probably isn't in the pan.

So i'll agree with the suggestion above, get a real oil pressure gauge and if the pressure it low, worry about an entire rebuild, not just killing yourself to change the pump with the engine in the car.
 
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