Oil leak at oil pressure sending unit. (HELP)

[langester]

I have installed 2 different oil pressure sending units on my 302 in the last 1000 miles. They last a while but then start to drip, looks like at the seam at the base, not sure oil is everywhere. I have the extension that comes out of the block on the drivers side with the sending unit mounted on the end it is a stock extension as far as I know.
Is there another place on the block to put the sending unit? I would love to eliminate it from that spot. With the power steering pump and lines, headers and oil filter in the way its a pain to fix every time it leaks.
My motor does have a high output oil pump, not sure if that is causing an issue. I am buying my sending units at my local Carquest, they are supposed to be good quality, but I know that is a relative term these days.
Open to any and all suggestions that anyone has.

Thanks in advance!

 

[73azbronco]

triple check it's not dripping off valve cover or out extension off the block, No other good location to tap for oil pressure sorry

 

[langester]

I figured that was the only spot. I know its not the valve cover, checked it multiple times. It is either the extension or the sending unit. I suspect the sending unit again just because its leaking again. It seems to last for 2 or 3 hundred miles and then here it comes again. I can't see in that area very well without taking the power steering pump or the oil filter off. Wish I had a small cable camera, might be a good excuse to get one.

Thanks for the reply! I appreciate the help!

 

[DirtDonk]

The old aluminum ones were notorious for splitting, or actually snapping off the threaded end at the block. If yours is aluminum, definitely look closely at it while you're narrowing down the possible locations.

Paul

 

[langester]

Thanks Paul! I think I will order a new one just to eliminate that part. I am tired of taking everything apart for a little problem.

 

[KyleQ]

If it is a mechanical gauge put some PTFE tape on the adapter and sensor.

 

[hatleyjm]

KyleQ, does the tape interfere with the sensor grounding? Asking for a friend...

 

[CA650]

this problem is terrible. i’m on my 3rd one also.
the next thing i’m going to try is a braided/stainless hose with NPT to AN fittings.
I tried various heavy duty sensing unit stalks.

some of them have angled ports for the the sending unit, I don’t recommend those because it’s impossible to get them right without having the sending unit positioned directly into the oil filter.

right now I have the port plugged completely. I was fed up with it so I cut off the end of the extender and welded a bolt into the hole so i have no pressure gauge at the moment.

I feel for you.

below is a picture of my current “solution”
I tried this extender that everyone sells. I ended up literally cutting the end off of it, re-threading it, and driving a bolt into the new threading to plug the hole.

I may make a part for this which i’ll share with the community here to fix this f-ng thing once and for all.

 

[Slowleak]

I went to Home Depot and picked up a short piece of NPT brass pipe and a fitting. Cost a couple of dollars and it’s been working fine for years.....I don’t trust those aluminum ones.

 

[gr8scott]

some of them have angled ports for the the sending unit, I don’t recommend those because it’s impossible to get them right without having the sending unit positioned directly into the oil filter.

Hmm...must be a problem with the newer ones? 20 years ago I took the old steel one out of my old block and
installed it into my new block and it lined up right where it needed to be.

 

[langester]

I have used paste and tape on the threads, gauge reads fine. I don't think its coming from the connection at the block, I think its coming from the sending unit side, oil is dripping from the edge of the sending unit where the rolled edge is. I might give the brass fittings a shot until I get a new extension. My extension does come out correctly, it is easy to thread the sending unit in and it does not interfere with the oil filter. You just cant see anything or get to it without removing a few things, makes it hard to see exactly where the leak is.

Thanks for all the replies and the pics! I appreciate the help!

 

[DirtDonk]

KyleQ, does the tape interfere with the sensor grounding? Asking for a friend...

No ground on a mechanical gauge. Just fluid flowing into a tube.
It can theoretically interfere with an electric gauge sender, but usually if you use only a moderate amount you're ok. And new ending units usually come with a dab of sealer of some kind on them to begin with.

Paul

 

[DirtDonk]

CA650, yours looks like aluminum. Is it, or is it steel and the zinc plating makes it look that way?
Is it from us, or someone else? If aluminum, I did not know you could even still get the aluminum ones, but that might be due to Mustang restoration people demanding it for accuracy.

I just re-checked and ours are steel.
If that's one of ours and is aluminum, then whoever checked didn't use the right technique!%)

Paul

 

[jckkys]

The original stalk was steel not aluminum. You won't find or make a stronger part. The Motorcraft pressure sending unit is available at RockAuto here;https://www.rockauto.com/en/moreinfo.php?pk=386505&cc=1105894&jsn=610&jsn=610. The oil pressure idiot light switch fits without the stalk. The oil pressure sending unit won't.

 

[CA650]

CA650, yours looks like aluminum. Is it, or is it steel and the zinc plating makes it look that way?
Is it from us, or someone else? If aluminum, I did not know you could even still get the aluminum ones, but that might be due to Mustang restoration people demanding it for accuracy.

I just re-checked and ours are steel.
If that's one of ours and is aluminum, then whoever checked didn't use the right technique!%)

Paul

it’s from wild horses and it seems to be aluminum
and it didn’t work for me.

not sure what you mean by not using the right technique.

when twisted tight it put the sending unit into the oil filter.

 

[CA650]

CA650, yours looks like aluminum. Is it, or is it steel and the zinc plating makes it look that way?
Is it from us, or someone else? If aluminum, I did not know you could even still get the aluminum ones, but that might be due to Mustang restoration people demanding it for accuracy.

I just re-checked and ours are steel.
If that's one of ours and is aluminum, then whoever checked didn't use the right technique!%)

Paul

it’s from wild horses and it seems to be aluminum
and it didn’t work for me.

not sure what you mean by not using the right technique.

when twisted tight it put the sending unit into the oil filter.

 

[DirtDonk]

I meant at our end. And "technique" was just a generic way of saying they were not diligent in their checking just a few days ago. And that when in doubt, use a magnet or something.
Either that, or at some point we got some aluminum ones in our orders when they were supposed to be steel.
But then I doubt that we specified that they had to stay that way to the supplier. We likely assumed they'd keep sending us the same part we expect to receive any time we ordered it.
Now there is a question and I'm going to pass it on to watch out for a difference.

Paul

 

[CA650]

I meant at our end. And "technique" was just a generic way of saying they were not diligent in their checking just a few days ago. And that when in doubt, use a magnet or something.
Either that, or at some point we got some aluminum ones in our orders when they were supposed to be steel.
But then I doubt that we specified that they had to stay that way to the supplier. We likely assumed they'd keep sending us the same part we expect to receive any time we ordered it.
Now there is a question and I'm going to pass it on to watch out for a difference.

Paul

hmm ok
can I have a steel one?

 

[KyleQ]

I'm running a generic cheapo ebay aluminum one on two engines with multiple sender swaps without any leaking. Running either an ancient (just failed) Ford racing mechanical gauge or an Equus electric unit. The Equus stuff really has me impressed at the price point, I've power washed the tach and gauges for years without a single failure.

 

[DirtDonk]

Workin' on that angle CA. PM me your customer info for starters please.

Thanks

Paul