Oil pressure switch testing
Thread Starter
Advanced
Joined: Apr 2016
Posts: 53
Likes: 2
Oil pressure switch testing
Is there a way to test the oil pressure sending switch to see if it's working? I want to test it before I get into the gauge. 1969 small block. Thx, Bob
Last edited by Cigars4me; Apr 26, 2016 at 09:27 PM. Reason: Add more info
Safety Car
Joined: Apr 2006
Posts: 4,057
Likes: 421
From: BC
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,114
From: Crossville TN
Not necessarily. The tubing could be pinched, broken or plugged. In fact, a plugged line is not that unusual.
Folks get all wierd about testing a mechanical 'oil' pressure gauge. Well, an 'oil' pressure gauge will check the pressure of about anything, since it is a Bourdon tube (mechanical) type of gauge. So, you could test it will air pressure [lots easier than checking with oil].
The biggest concern is damage to the plastic (or copper) line. Over time, both copper and nylon get hard and brittle. So, an old line can be damaged just from movement. But, your gauge doesn't work, anyway...so what the he!!.
Remove the nut which holds the tubing in place, remove the plastic line, then remove the fitting from the block. Now, put the parts back together, but don't connect it to the block. Instead, come up with the adapter needed to hook up your air compressor to the line fitting. Assuming you have a pressure gauge on the air compressor, you can fire it up and put pressure on the Corvette feed line and gauge to test it out. And, you can even put substantially higher pressure on it than what your engine's oil pressure would ever reach. Exercising that gauge between 10 and 80 psi could very easily break a plug of caked oil loose in the line and get the gauge mechanism working again. You don't even have to remove the gauge from the car.
Just present as little flexing to the feed line as you possibly can, as that is the greatest risk to damaging it. If it does get damaged, hopefully the damage will be in the engine bay area and you can splice a new piece of line to the old one and keep it working without having to open up the gauge bezel.
Worth a try, anyway. If you replace the gauge, you have to dig into the bezel. {Something to avoid, if at all possible.}
Folks get all wierd about testing a mechanical 'oil' pressure gauge. Well, an 'oil' pressure gauge will check the pressure of about anything, since it is a Bourdon tube (mechanical) type of gauge. So, you could test it will air pressure [lots easier than checking with oil].
The biggest concern is damage to the plastic (or copper) line. Over time, both copper and nylon get hard and brittle. So, an old line can be damaged just from movement. But, your gauge doesn't work, anyway...so what the he!!.
Remove the nut which holds the tubing in place, remove the plastic line, then remove the fitting from the block. Now, put the parts back together, but don't connect it to the block. Instead, come up with the adapter needed to hook up your air compressor to the line fitting. Assuming you have a pressure gauge on the air compressor, you can fire it up and put pressure on the Corvette feed line and gauge to test it out. And, you can even put substantially higher pressure on it than what your engine's oil pressure would ever reach. Exercising that gauge between 10 and 80 psi could very easily break a plug of caked oil loose in the line and get the gauge mechanism working again. You don't even have to remove the gauge from the car.
Just present as little flexing to the feed line as you possibly can, as that is the greatest risk to damaging it. If it does get damaged, hopefully the damage will be in the engine bay area and you can splice a new piece of line to the old one and keep it working without having to open up the gauge bezel.
Worth a try, anyway. If you replace the gauge, you have to dig into the bezel. {Something to avoid, if at all possible.}
