Oil Pressure sending unit

Bruce Parker (RIP) · #1 09-06-08, 03:51

I'm having a little problem with my oil pressure sending unit. The manual says it's manual gauge and to run an oil line from the engine to the gauge...except... my project has an electric gauge (original) in the dash and therefore requires some kind of sending unit in the engine. What kind should I be looking for and where should I put it to read the pressure correctly? 12 volt system on a GMC 270.

Lynn Eades · #2 09-06-08, 06:12

The electric sender has to be compatable with the guage. some one else will have to help you with that. Where to put the sender? ....Into the main gallery in the side of the block. I'm not familiar with the details of the 270 gmc motor, but there is an oil gallery along the side of the block which possibly has one or two blanking plugs, and one of them will do the trick.(opposite side to the camshaft) (If there was an oil supply to the mechanical guage. Put the sender into the same place)

Phil Waterman · #3 09-06-08, 16:34

Hi Bruce

I've seen the solution to this problem listed on some of the HOTROD Chevy Stove bolt 6 sites. If I remember correctly the solution is a dropping resistor which supplies 6 volts to the instruments temperature sensor, oil pressure and gas gage. Changing the early 50s Chevys over to 12 volts when hotroding the engine or replacing with a V8 was very common.

Try a google search on "6 to 12 volt conversion chevy" http://www.google.com/search?hl=en&q...=Google+Search you should get a number of good write ups. I saw a number of sources for the conversion resistor.

I have a friend that converts all of his CCKWs to 12 volt and he uses the dropping resistor to convert the gages. I'll ask him what resistor he uses.

Cheers Phil