Stripped oil pressure sensor thread

[MattPro]

I bought a turbo kit from another member on here, and when I was installing the feed line I was tightening down the adapter that fits in place in the oil pressure sensor location. Apparently the thread wasn't right, as after tightening it loosened up instantly. Going in it seemed to be fine, but right when it started getting snug it gave out.

It's pretty obvious the threads are stripped. I figured if I could JB weld the thread and base it would seal fine, and I didn't care since I would never be taking it out. But that didn't work, the car is running now but it has a small drip from the adapter. I can deal with the drip as it is very small but I would like to get it fixed.

My question is what are my options now? I did notice that the thread goes very deep into the block, could I get a longer threaded pipe with the correct threading and just run it deeper into the block? Or did I screw myself over?
I can easily get the JB weld out, it seems like it didn't even harden at all so that's not an issue.

Thanks.

[jalopi]

If you really destroyed the first half of the threads, then yes, you might be able to get away with a fitting that has an extra long thread piece.

However, the more realistic situation is that you're going to have to either repair the threads or helicoil it. Considering that it's cast iron, you'll probably be able to repair the threads with the right size tap - you'll have to find that out yourself. Otherwise, helicoil is the way to go. In case you're not familiar with the concept:

They were made specifically for stuff like this... stripped oil pan threads, ect. Basically, you drill the hole with a specifically sized drill bit. Then, you tap the hole with the included tap. Then you install the helicoil into the big hole to make the big hole a smaller hole.... the size it's supposed to be.

Don't recall exactly where the oil pressure sensor is on m20s, but I'd wager that you're not gonna have fun doing this.

[MattPro]

If you really destroyed the first half of the threads, then yes, you might be able to get away with a fitting that has an extra long thread piece.

However, the more realistic situation is that you're going to have to either repair the threads or helicoil it. Considering that it's cast iron, you'll probably be able to repair the threads with the right size tap - you'll have to find that out yourself. Otherwise, helicoil is the way to go. In case you're not familiar with the concept:

They were made specifically for stuff like this... stripped oil pan threads, ect. Basically, you drill the hole with a specifically sized drill bit. Then, you tap the hole with the included tap. Then you install the helicoil into the big hole to make the big hole a smaller hole.... the size it's supposed to be.

Don't recall exactly where the oil pressure sensor is on m20s, but I'd wager that you're not gonna have fun doing this.

Thanks, that's what I was fearing. I don't have a tap set currently, so I was trying to find alternate methods to try first. I can see the threads are not totally destroyed, and the fitting actually starts to get tight currently then slips.

I've been trying to find a pipe or adapter with a long threaded area and haven't been successful, I could try adding some thread with a die but once again that's back to buying a tap/die set.

Luckily, the location for the oil pressure sensor is easy to get to, I can just jack the car up and look straight up at it, there's nothing in the way.

Thanks for the input!

[jalopi]

Are you sure the threads in the block are screwed, or is it the adapter/fitting? My chips are on the adapter threads being gone... cast iron typically doesn't play games with softer metals.

Also, you can buy taps and dies individually - look up your closest fastenall or whatever and they should have one.

[MattPro]

Are you sure the threads in the block are screwed, or is it the adapter/fitting? My chips are on the adapter threads being gone... cast iron typically doesn't play games with softer metals.

Yeah, sadly I pulled the adapter out before trying the JB weld and its threads were fine. There were a couple chunks of metal on them and they weren't missing any, so it was definitely from the block. I also tried threading the stock adapter back in and it wouldn't thread in very far so I just backed it out.

I really don't understand why the JB weld didn't harden up, I cleaned out the threading really well and did a 50/50 mix like the directions said...but that's a different story I guess haha

[jalopi]

How long did you give the JB weld to cure? I did something ghetto like this when I was in my teens and did my first turbo setup... 92 miata... massive pile of shit. I didn't strip the threads in my block, but I had no idea where I could find the right parts so I filed the threads off the fitting I bought (from home depot) and JB welded it in there... yes you read that right. Now, this was almost ten years ago so my memory is a bit fuzzy.. but I think i had a very very minor dribble from the JB welded supply line. Can't say how long it would've lasted in the long run because the head gasket went up after three months or so.

Anyway, I used to use the stuff alot back in the day and it seems that JB weld takes at least 24 hours to cure in colder environments. Might be your problem, maybe. However, instead of the JB approach, I'd still try to tap it.

[MattPro]

How long did you give the JB weld to cure? I did something ghetto like this when I was in my teens and did my first turbo setup... 92 miata... massive pile of shit. I didn't strip the threads in my block, but I had no idea where I could find the right parts so I filed the threads off the fitting I bought (from home depot) and JB welded it in there... yes you read that right. Now, this was almost ten years ago so my memory is a bit fuzzy.. but I think i had a very very minor dribble from the JB welded supply line. Can't say how long it would've lasted in the long run because the head gasket went up after three months or so.

Anyway, I used to use the stuff alot back in the day and it seems that JB weld takes at least 24 hours to cure in colder environments. Might be your problem, maybe. However, instead of the JB approach, I'd still try to tap it.

It sat for around three days...that really leads me to believe I might not have used as much hardener as I thought. Maybe I messed up mixing it up or something, or maybe JB weld can expire, it was very old. I'm not sure.

And I will try to get my hands on a tap, I want to do this right but being a college student working in front of my apartment in a parking lot makes it hard. I really wanted to avoid the JB weld approach from the start but I didn't have many other options at the time. This is the only corner I've cut on this project and it came back to bite me already.

Thanks again for all of the advice!

[jalopi]

FYI, tooltopia is a good place to buy tools. Individual taps on the cheap:

http://www.tooltopia.com/hand-tools-taps-and-dies-individual-taps.aspx

Used to use them all the time when I was still a mechanic. Pretty quick shipping, also free if over $100... at least it used to be. Not sure if it still is.