Oil pressure sender fitting

[Tory S.]

I can't seem to find the right fitting/adapter to fit the oil sender to the block ('75 350). I got one from one of the parts companies but the male threads were too big - 1/2" I think. It was GM #10052990.

My AIM gives a discontinued GM #6258296. The hole in the block seems to be 7/16"-14. The part is a short brass fitting about 3/4" long. Paragon shows a part #7145 but it's only 1/4" OD and it's 2" long.

What is the right adapter and where can I find one?

Thanks,
Tory
'75 Conv.
Original owner

[Joe L.]

Re: Oil pressure sender fitting

I can't seem to find the right fitting/adapter to fit the oil sender to the block ('75 350). I got one from one of the parts companies but the male threads were too big - 1/2" I think. It was GM #10052990.

My AIM gives a discontinued GM #6258296. The hole in the block seems to be 7/16"-14. The part is a short brass fitting about 3/4" long. Paragon shows a part #7145 but it's only 1/4" OD and it's 2" long.

What is the right adapter and where can I find one?

Thanks,
Tory
'75 Conv.
Original owner

Tory-----


There was a replacement for the GM #6258296 bushing. It was GM #14022026. Unfortunately, it was discontinued without supercession in October, 1994.

The tapping in the block is NOT 7/16-14. It's 1/4" NPT (i.e.pipe thread). The bushing adapts the block's 1/4" NPT to the oil pressure sender's 1/8" NPT. It's a very simple and common bushing-----you can buy them in a hardware store, although they likely won't be configurationally correct.

[Joe L.]

Re: Oil pressure sender fitting

I can't seem to find the right fitting/adapter to fit the oil sender to the block ('75 350). I got one from one of the parts companies but the male threads were too big - 1/2" I think. It was GM #10052990.

My AIM gives a discontinued GM #6258296. The hole in the block seems to be 7/16"-14. The part is a short brass fitting about 3/4" long. Paragon shows a part #7145 but it's only 1/4" OD and it's 2" long.

What is the right adapter and where can I find one?

Thanks,
Tory
'75 Conv.
Original owner

Tory-----

The below-referenced might work for you if you want a shorter bushing than, apparently, Paragon has available.

http://www.mcmaster.com/#4757t91/=3v1nqr

[Tory S.]

Re: Oil pressure sender fitting

Joe,
You seem to have all the great answers. Thanks. Now I have choices!

So which length fitting is correct - the 2" long one from Paragon or the short one you sent in the link? How long were the GM ones - original GM #6258296 and replacement GM #14022026?

Thanks,
Tory

[Joe L.]

Re: Oil pressure sender fitting

Joe,
You seem to have all the great answers. Thanks. Now I have choices!

So which length fitting is correct - the 2" long one from Paragon or the short one you sent in the link? How long were the GM ones - original GM #6258296 and replacement GM #14022026?

Thanks,
Tory

Tory----


Well, it just goes to show you that I don't have an answer for everything----I don't know how long those were. However, if yours is 3/4" long, you're the original owner of the car, and you're reasonably sure no one has ever replaced it, then I'd say the original for your car must have been about 3/4" long. VAGUELY, I thought they might be a bit longer than this, but yours seems to indicate otherwise.

[Tory S.]

Re: Oil pressure sender fitting

Joe,
I must have misled you. I do not have my original fitting. When I referred to the one that I have, it was the GM replacement sent to me by Dr. Rebuild and looks like the one you found at McMaster. It did not fit - too big. So I have no idea, except the picture in the AIM looks short again like the one at McMaster . However Paragon claims their 2" long part is a reconditioned part fopr 75-79.

Before I had no fitting, now, thanks to you, I have TWO choices. So do I go long or short? What do you think?

[Joe L.]

Re: Oil pressure sender fitting

Joe,
I must have misled you. I do not have my original fitting. When I referred to the one that I have, it was the GM replacement sent to me by Dr. Rebuild and looks like the one you found at McMaster. It did not fit - too big. So I have no idea, except the picture in the AIM looks short again like the one at McMaster . However Paragon claims their 2" long part is a reconditioned part fopr 75-79.

Before I had no fitting, now, thanks to you, I have TWO choices. So do I go long or short? What do you think?

Tory-----


The GM #6258296 busing was used from 1975 thru 1979. So, if what Paragon is selling is a reconditioned original piece, I don't know how you could go wrong. At first, I thought that what might have happened was that the bushing (and part number) changed over the 75 to 79 period and what they had was a reproduction of one possibly used later in the period but usable for earlier. That does not appear to be the case.

Why did the one you got from Dr. Rebuild not fit? Although I don't have any direct experience with this installation, it would seem to me that one would be better off with the shortest possible bushing. All that's being accomplished here is adapting the 1/4" NPT block size to the 1/8" NPT pressure sender thread size. I don't see why it should need to be "spaced out" further from the block than is necessary. I don't even think that's desirable.

[Tory S.]

Re: Oil pressure sender fitting

Joe,
I agree with you on why it would be good to space out the sender on a longer bushing. Seems shorter would be better.

The one I got from Dr. Rebuild was GM #10052990 and was too large diameter to thread into the block, but it was about 3/4" in total length.

I've called Paragon and they are researching the GM part number to their part. Let's see what they come up with.

Sorry to be such trouble for such a small part.

Tory