oil pressure sending unit?

[77c15]

I am having an issue with the 72 350 I just put in my 74. I have a line/tube coming out of the firewall that is, as far as I know, supposed to go to the backside of the block, just offset from the rear of the distributor hole on the manifold. I work at AutoZone part time, and all we have is a swith, wich won't work considering I don't have an electrical connection to the gauge. Also,   doesn't list anything about this either. I check to see if maybe the threaded fitting on the end of the tube would screw into the block, but it's too small. The switch that I picked up at work (PS24) threaded in the hole fine, but has a terminal for an electrical hookup. Any ideas guys?

[red4wd]

The fitting in the block is 1/8" pipe I believe...the line coming from the fire wall is more than likely some sort of flare fitting.  What you need to do is get an 1/8th pipe to flare fitting and you should be in business.

[Lt.Del]

Here's what my 79 350 oil sender looks like...it is just screwed in with no extension, right next to the distributor...

[77c15]

I'm not sure if I made it clear in my post, but I have a gauge, not a light. Also, thanks Del for the pic. I really think I left that part of it connected to the 383 that was in my truck (WAY too many coolnig issues and head gaskets!).   doesn't have anything like that. I'm planning on going with AutoMeter gauges in the future with one of those Covan's Classics cluster pieces, but money is not permitting that currently (more interested in getting it running and purchasing the fenders and core support). Anyone know where I can pick up the part Del has circled in his picture? Thanks!

[red4wd]

Do you have a metal line coming out of the firewall?

[Captkaos]

What Del posted is an electrical sending unit, it won't do you any good. 

The gauge has GM specific ferrule and fitting on the back and isn't the same as normal ones, so if you are missing the piece off the back of the gauge AND the one in the engine, you are going to be disappointed, as you need both.  I have tried making "normal" lines work, but the end up leaking, or blowing off most of the time..

I am assuming the cluster came out of a 76-77 as the mechanical gauge is unique to those years.  If you are putting it in a '74, make sure you use the 76-77 wiring as they won't interchange between those years without frying the wiring harness.