Oil Gauge Sending Unit - How Attached?

[El Matador]

This question pertains to cars with the floor gauge package, which includes an oil pressure gauge.

The sending unit for this gauge is attached to the passenger side of the engine block, back near the firewall.  The question is, HOW exactly is it attached and how do I remove it?  Is it simply pressed into a hole and can be pulled straight out, or is it threaded in and must be unscrewed to remove?

I'm asking this because I want to remove one from a junkyard car before it vanishes.  I gave it a few taps with a hammer and got it to turn counterclockwise a bit, but it was very stiff.  It's pretty oily and greasy, and I felt around there looking for a bolt head or some obvious clue but found none.  Just came away with a very black hand.

[shaggimo]

Never seen an oil sender that didn't thread out, but have broken off a few due to them being aluminum vs the cast block  . I'd just bring some good penetrating oil, and slowly work it back and forth it may come out.

[amcinstaller]

yea, ill second shag. there should actually be flats on the outermost edge of the unit, but also just like shag, most that ive seen break off. also, there may be a T fitting for the dummy light switch that you could pull there, just take the whole lot.

[El Matador]

As I recall, it was an L shaped fitting with the sending unit for the optional gauge on one end, and the wiring for the standard dash light on the other end.  My plan was to take the whole thing.  I did get it to turn slightly but it was very tight.  Only a hammer could move it, I couldn't turn it by hand.

I'll take some WD40 with me next time, and soak the area where it enters the block.  If it is indeed threaded then I won't try to turn it clockwise.  I may have to separate the sender from the L fitting first, because with it still attached I don't think there's room to turn the whole assembly through a complete revolution.

[mudkicker715]

Should be regular old pipe thread.

[DaemonForce]

Should be regular old pipe thread.

Confirmed. Removed that nasty oil-biscuit from my spare block the other day.

[amcinstaller]

i have to apologize and retract part of what i said. the outermost edge flats are on the dummy light bit, not the gauge part. the flats for turning the gauge sending unit are close to the threads at the base.