The factory thread is 1/8" BSP. Did you replace the sender with a Toyota one or aftermarket? If you have to drill larger hole for heli-coil you risk getting metal chips in the oil passage. If I remember correctly 1/8" BSP will thread into 1/8"NPT but not visa-versa. Take the pressure switch somewhere that has NPT fittings and see if it will screw into a 1/8" NPT and gives you some tightening. If so I would re-tap the existing sender hole with a 1/8" NPT tap. You can smear grease on the tap which will catch the metal chips cut by the tap. Then use a cuetip to clean out anything in the cut thread and clean the hole of grease and oil. Use Permatex High Performance Thread Sealer on the sender threads and let sit overnight. You'll have to be careful not to overtighten. If the BSP does not tighten in the NPT then you may have to install an aftermarket gauge with an NPT sender. I re-tapped my BSP oil sender thread to install a NPT aftermarket mechanical gauge without drilling and it worked great using the above method. Other option would be to source a 1/8" NPT male to 1/8 BSP female adapter - AutoMeter may carry one.

Yet another option would be to re-tap with a 1/8" BSP tap - if you can find one. The hole thread is a taper thread so more turning will cause it to tighten, if it has threads.

Maybe someone else has more options.

 

well it looks like more of a problem than just stripped threads now. It looks likea piece of the block around where the oil pressure sending unit goes in broke off. Now I got a fairly large hole looking into the block, and I need help determining what I can do to patch this up. Can I just plug it up with some kinda metal filler and not even have an oil pressure sending unit? I'll post pics soon.

 

Yes to using metal repair, the valve head is cast aluminum, you must clean it very well, then If I were you, use white gas (Naptha) then brake cleaner. Rough up the exterior, and then use metal filled epoxy putty and push a fiberglass cloth on the exterior, then some more putty on outside. Smooth out with wet finger.

You can try and keep oil pressure sender by epoxying in a threaded insert (like helicoil)

Your oil pressure lamp will be on all the time without the sender.

 

I really would NOT recommend doing this. Seems to me this is REALLY bad advice. :disappoin

Id also take it to a machine shop and see what they would recommend, but it looks to me like you'll need to replace it with one from a junker. :sosad:

 

This is going to be very difficult to repair, maybe not possible, especially if you want a gauge sender in there. Metal epoxy may work but the problem is you'll have to rely on the epoxy "sticking" to the aluminum AND holding against 40-60 psi. You may want to talk to a machine shop to see if there is any way they can repair it. Removing the head for repair may also be your only option. This may be the time when a junk yard head is the best route. I suspect you attempted to tighten the sender too much and because it is a taper thread it burst the side off the head.

 

Do you have any update about your problem? Because I did the same stupid mistake on my Camry and torque the sensor too much and cracked the block (not as much as you, but it's a 1 inch long crack that is less thick than a hair). Have you finally fixed it? or did you replace the block?

 

i ended up using JB-weld with a threaded-extension piece of metal. It's been holding up since August 2008 no problem. If yours isn't nearly as bad, i suggest using JB-weld. Cheap and easy fix.