1941 OIL PRESSURE SENDER

[John R. Hess]

Hi Everyone

 

I have a question for which I have not found any answer by checking the service manual for this car.   I am trying to find out what "sends" the oil pressure reading to the dash gauge.    Is there a sender as there would be on a 60's car?  I am experiencing varying oil pressure readings on the original dash gauge, varying from 15 to 30 psi, while driving at a steady speed.  For a very brief moment, it dropped to almost zero and quickly returned to 15.  At this point, I have no idea whether there is an oiling problem or a "metering" problem.  Would it be possible in insert an oil pressure gauge into the place where current gauge gets it's feed?

 

Thanks in advance for any help.  The car is a Super, the engine is the original 248 cid with the compound carburetors.

 

John Hess

[ILIKECARS53]

There is not a separate oil sending unit. Oil sending units were used on electric gauges.   1941 Buicks were mechanical gauges. The actual pressure is read by the gauge. Yes you can hookup a gauge at the engine block to check the pressure.

[EmTee]

As noted above, it's a mechanical pressure gauge.  An oil line runs from the engine to the gauge.  You could try disconnecting the line from the gauge and engine and blowing compressed air into the gauge end.  wrap a rag around the engine end to catch whatever comes out.  It sounds like there could be something (e.g., a piece of sludge) that is intermittently blocking the line.  You could try carefully spraying some solvent (like WD-40) into the gauge connection to flush it out also.

[Ben Bruce aka First Born]

The line Em Tee is talking about is connected to the oil galley just beneath the distributor and runs up through the cowl to the gauge. 1/8th inch I believe. Obtain an aftermarket mechanical gauge . It will come with a tubing that can be connected where the original is, or better yet, to the oil galley that runs from front to back a couple inches above the oil pan rail/flange.  There are plugs that can be removed and the new gauge tube installed.   I believe this new gauge and the old will mimic each other. Thinking the oil pickup screen is plugged. Hope I am wrong.

 

  Ben

[neil morse]

3 hours ago, EmTee said:

You could try disconnecting the line from the gauge and engine and blowing compressed air into the gauge end.

The only thing I would add to what EmTee says is that, on the '41, it is very difficult to get access to the back of the gauge to disconnect the line unless you remove the whole instrument panel.  And that is not a task that should be undertaken lightly.  It can be done, but it's a major job for sure.  I would try everything else first.  Putting in an aftermarket gauge and comparing the reading you get will tell you a lot.

[DonMicheletti]

You may not have a gage problem at all.

Your symptoms are right line with those of a plugged oil pump pickup screen.

Has the engine sat for vely long periods of time without running?

I'd drop the pan and check the screen and pump.

Clean and check everything.

Pulling the pan on a '41 isnt easy, but is possible.