Need a recommendation for an oil pressure sender

[Papa]

I need to get an oil pressure sender that will thread into my 302 block and work well with the FF Vintage gauges. Can anyone provide a recommended part number? The threaded hole on the top rear of the block looks like 1/8" NPT (caliper measured 0.40" wide).

Thanks,
Dave

[JRL16]

Check out Speedhut. That’s where the gauge is from.

[Papa]

Okay, I feel like a dummy now. I went out and pulled the box the gauges came in and there was the sender. Now I just need to figure out what adapter I need to fit the port on the block. The one supplied with the gauge is too large.

[rich grsc]

I don't know of any oil ports on the top rear of a 302 block?

[Papa]

I don't know of any oil ports on the top rear of a 302 block?

Well, now I'm really confused. I assumed this was an oil sender port:

https://farm5.staticflickr.com/4513/26301743569_142887d91d_b.jpg (https://flic.kr/p/G5cj2p)

... but, after getting the flash on the camera to shed a bit of light on the subject, it looks like it goes nowhere. Where would I find the correct place to put the oil pressure sending unit on a 302 block?

Thanks,
Dave

[Papa]

Okay, this has to be it (right near the oil filter where the brass plug is)?

https://farm5.staticflickr.com/4446/37369134514_e1bb0a9825_b.jpg (https://flic.kr/p/YWbzLE)

[Chuck Sloggett]

Port is on drivers side front of block near the oil filter. -- Chuck

[karlos]

Unless your sending unit is smaller than the one I received you'll probably need an adapter to get it to clear the oil filter. The 45-degree fitting in the first photo works well. The second photo shows another popular option (Summit part # SDK-C2OZ-9B339-C) that also works fine if you don't mind the long cantilever.



http://thefactoryfiveforum.com/attachment.php?attachmentid=76178&d=1509506490



http://thefactoryfiveforum.com/attachment.php?attachmentid=76177&d=1509505938

[Bobby Doug]

Karlos,

If those are brass fittings between your block and oil pressure sending unit you might want to change them out. My engine builder has told me they will BREAK, it is just a matter of when.

Doug

[scottiec]

Bobby is right. Don’t use brass adapters like that

[CraigS]

When you look for the long one,which is available from several sources, be sure to get one made from steel. They are not all steel.

[edwardb]

Used this extension on #7750. Steel and fit perfectly. Recommended. https://lmr.com/item/LRS-9278A/1979-89-Mustang-Oil-Pressure-Sending-Unit-Extension-50L. Something like this is pretty much mandatory if using a mechanical fuel pump. Pictured here on my build.

http://i867.photobucket.com/albums/ab234/edwardb123/Factory%20Five%20Mark%204%20Roadster%20Build/Engine/IMG_2207_zps796095af.jpg (http://s867.photobucket.com/user/edwardb123/media/Factory%20Five%20Mark%204%20Roadster%20Build/Engine/IMG_2207_zps796095af.jpg.html)

[Jeff Kleiner]

Papa,
The tapped blind hole shown in your photo is for a knock sensor (only used in pickups and vans but machined on all 5.0/302 blocks sometime after the mid 1980s).

I second or third the caution about using brass hardware.

It's no secret that I have a love/hate relationship with Speedhut after experiencing a number of failures on various builds which includes at least 3 oil pressure senders. After the second failure on the same car within <2,000 miles I installed an NPT to AN fitting at the pressure port and remote mounted the sender to the inside of the F panel then used a section of #4 braided hose between them. Can't say for sure that the sender failures were vibration related but there have been no further issues in the 10K+ miles since... Just another option to consider.

Jeff

[karlos]

I am in fact using brass. Thanks for the warning. A little research courtesy of Google shows that the brass can potentially strain harden and then crack. Obviously not a good place for a pressure-fed leak. All the same fittings are available in steel, so I’ll go ahead and swap them out. Thanks again.

Jeff: the failures you mentioned were what, cracks through the threaded portion of the sender?

[Jeff Kleiner]

Jeff: the failures you mentioned were what, cracks through the threaded portion of the sender?

No, the senders failed electrically.

Jeff

[RR20AC]

Looks like my sender is starting to fail, so this post is timely for me. Is there an after market part number for this sender. Sounds like they fail quite frequently.

[edwardb]

Looks like my sender is starting to fail, so this post is timely for me. Is there an after market part number for this sender. Sounds like they fail quite frequently.

Everybody's experience is different I guess. I've used the Speedhut oil pressure sensor on two builds. Multiple years of driving between the two and no failures. Yours is so new, have you called Speedhut? They are good at customer service. Maybe they would replace it.

I personally don't know if another part would work or how unique the Speedhut one is. They list is as "Resistive Pressure Sensor - 100 psi, 240-33 Ohms" but just a quick scan through a couple sites (e.g. Summit) they don't list the resistive values. Plus most appear to have only one wire connection vs. two like the Speedhut. Probably could be grounded directly to the block, but don't know that for sure either.

[RR20AC]

Thanks Edwards, your observations are mine exactly and I’ll have to call speedhut tomorrow. Some of those sensors look close but don’t have both contacts. Gauge worked well for about 500 miles and now fluctuates from were it was reading down to zero.

[Papa]

Thank you everyone once again. I ordered one of the extenders. I'm sure I'll have many more questions as I start making all the connections needed to get to the point where I can start this thing for the first time.

Dave

[boat737]

Also, be very careful installing and hooking it up. That unit is pretty fragile, and those terminals seem to break pretty easily.