Oil sending unit/switch

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Ruger64

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I bought a really nice set of electrical gauges from summit
Went in the garage to install them. But no luck. I located what I believe would be the stock oil sender to remove under the oil filter? There was 41 years worth of crud on and around it. I chipped away at the crap and tried to loosen it with no luck. I even managed to tap a socket on it and could not get it to budge even with a half inch ratchet. I stopped in fear of breaking it off. I wanted to use these gauges so badly. Any ideas? Its not easy to get to. And I surely dont want to snap it off. I never attempted the water sensor after that. Anyone run into this?
The new bell looking sender looked large too that came with the gauges. I dont know if it will even fit.
 
You may need a pipe wrench to remove it. The threads are pretty big, about 5/8" across so it can take some torque. If your new gauge has a 1/4", 27npt fitting you will need a 3/8", 18npt male to 1/4, 27npt female adapter, I believe.
 
PA…. Was the ambient air and engine temperature cold when you tried to remove sender? If so, sometimes threaded items of dissimilar material such as steel bolt screwed into aluminum gets real tight as temperature gets low from different rates of linier expansion. In other words aluminum tends to shrink and or expand twice the distance as steel per degree from room temperature. This expansion thing becomes more problematic if the bolt or device was installed on a hot engine. I don’t recall if the oil sending unit is steel in aluminum or not, but it has a funky pot metal shape to get a wrench onto it.

Warm engine up, and try it again.
 
phogroian said:
You may need a pipe wrench to remove it. The threads are pretty big, about 5/8" across so it can take some torque. If your new gauge has a 1/4", 27npt fitting you will need a 3/8", 18npt male to 1/4, 27npt female adapter, I believe.
Click to expand...

I don't think I can get a pipe wrench down inside there. It is really a tight area. I am not sure of the fitting size on the new sender. It has a big bell looking thing. Here is the gauges:

http://www.summitracing.com/parts/SUM-G2889/?rtype=10

And here is the sending unit if that helps?

http://www.summitracing.com/parts/sum-g2987


wjajr said:
PA…. Was the ambient air and engine temperature cold when you tried to remove sender? If so, sometimes threaded items of dissimilar material such as steel bolt screwed into aluminum gets real tight as temperature gets low from different rates of linier expansion. In other words aluminum tends to shrink and or expand twice the distance as steel per degree from room temperature. This expansion thing becomes more problematic if the bolt or device was installed on a hot engine. I don’t recall if the oil sending unit is steel in aluminum or not, but it has a funky pot metal shape to get a wrench onto it.

Warm engine up, and try it again.
Click to expand...

I didn't think of warming up the engine first. That may be an idea. I had a heck of a time getting to it.
 
All electric oil gauge senders that I'm aware of are "big." If it won't fit the stock location on your engine, find out if there is an alternate sender tap, or if not, you'll have to space it away from the engine with pipe fittings. Many guys like to use a tee so that they can retain the original oil warning lamp along with the gauge.

All these senders use U.S. pipe thread.

1/8 pipe thread is approx. 3/8" outside diameter

1/4 pipe thread is approx 9/16" outside diameter

3/8 pipe thread is approx 5/8" outside diameter

These are approximate, but with pipe thread, there is nothing in between. If you buy fittings be careful not to mix in other fitting types such as flare
 
To remove the sending unit from the oil pump, I struggled for a while, but then I locked vise grips on it and hit it with a hammer.....lol
 
O.K., from the specs on the sending unit link that you provided I'd guess that you need a male 3/8" 18 npt to female 1/8" 27 npt reducer fitting.


If you wish to retain the ability to use your stock warning light as well as the meter, I'd recommend a "street T" with a 3/8" male npt to two female 3/8" npt outlets (see attached photo). This may also serve to provide you with some working distance from the oil pump/filer holder assy if the sender is too pudgy to fit in close.

You can then put the stock switch into one section of the tee (if the thing survives the ordeal to remove it) or plug the extra hole for future use.
 

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roadrunnerh said:
To remove the sending unit from the oil pump, I struggled for a while, but then I locked vise grips on it and hit it with a hammer.....lol
Click to expand...

Harry, I am afraid to do that! LOL I was on it pretty hard. I am ready to just ship my gauges back to summit...LOL
I don't know how you got up inside there! Its tight up in there!

phogroian said:
O.K., from the specs on the sending unit link that you provided I'd guess that you need a male 3/8" 18 npt to female 1/8" 27 npt reducer fitting.

If you wish to retain the ability to use your stock warning light as well as the meter, I'd recommend a "street T" with a 3/8" male npt to two female 3/8" npt outlets (see attached photo). This may also serve to provide you with some working distance from the oil pump/filer holder assy if the sender is too pudgy to fit in close.

You can then put the stock switch into one section of the tee (if the thing survives the ordeal to remove it) or plug the extra hole for future use.
Click to expand...

Thanks for the help. I appreciate it. I know what the difference is with the 3/8's and 1/8th inch.
But what does that mean when you are saying the 18 npt and the 27 npt?
I am lost on that part? Sorry...:(
 
I think that's the fineness of the thread pitch. The threads will usually be a set pitch for a certain diameter- but it doesn't hurt to specify, since there are different thread,seal types. Unlike the flange types, the npt ones taper just slightly so that they snug themselves down as you screw them in.
 
You don't need to fool with thread pitch unless you've mistakenly entered a Beemer dealership. ANY hardware/ parts/ Lowe's etc that sells "pipe fittings" will be US pipe thread. All you need to know is whether you need 1/8, 1/4, etc, etc.
 
Now wait a second......................the oil pressure sender on my 273 is behind the distributor at the back of the block. I'm not saying that you couldn't tap into a passage near the oil filter. tmm
 
toolmanmike said:
Now wait a second......................the oil pressure sender on my 273 is behind the distributor at the back of the block. I'm not saying that you couldn't tap into a passage near the oil filter. tmm
Click to expand...

I believe he has a /6.
 
Oh I get it now. Sorry for the dumbness. Yeah, I have the slant.
I am going to try and get the car hot tomorrow, and then break it loose. I hope it works, and doesn't break off. ugh!!
 
AussiePlymouths said:
So, how did you go?

You got me in with this thread, so now I'm waiting to see???????
Click to expand...

I had to stop on that part for now. I went into the garage to start on it, and seen gas on the floor.
My car is in Mint Condition underneath, like new.
But the car sat for 15 years and the gas in it was bad.
The last guy put a old gas tank from another car in it, and now it is leaking. ugh! I need to grab a gas tank first now.
I just pumped all the gas out into 3.... 5 gallon gas cans...ugh!!!
 
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