BJ7 frozen temperature sensor to block

[Starstar]

Unfortunately, in the process of preparing my engine for removal/repair I discovered the most recent problem. Upon attempt to disconnect the temperature sensor at the block I discovered that it had been secured using loctite. That, and my many failed attempts to find a way to securely use a wrench upon the entire face of the connecting bolt head has resulted in he existing problem.

As I have struggled with all the steps resulting in the successful removal of the engine for quite some time I would greatly appreciate any aid or suggestions as to how to solve this problem.


Thanks,


Starstar

 

[dcarlg]

1. Cut the tubing.
2. Remove engine.
3. Remove sensor by any means necessary.
4. Plan to send the gauge off to be repaired.
5. Search previous threads for recommended gauge repair shops.
Good Luck.
Douglas

 

[RestoreThemAll]

I used a very deep well socket and cut a slice up the side so that it fit on the sensor nut and cleared the tube.

 

[Keoke]

I used a very deep well socket and cut a slice up the side so that it fit on the sensor nut and cleared the tube.

this is a very rewardng solution:eagerness:

 

[steveg]

I had the same problem. Attempted to remove using a cheap deep socket with slot as above. Socket kept bending enough to slip - even with hose clamp around it.

Russ Thompson was able to remove it using a deep impact socket with slot.

 

[John Turney]

I used a deep socket with a slot also. Wasn't a cheap one though.

 

[Keoke]

Russ Thompson was able to remove it using a deep impact socket with slot

Where in the world is Russ I have not seen him since the Austin Healey store folded in Sanfernado Valley???

 

[HealeyRick]

If it's been Loctited (talk about DPOs!) you'll need to release the Loctite first by heating the area in the cylinder head first. I'd probably use a torch with Mapp gas. While it's still hot you might try holding a candle to the threads of the sensor so the wax seeps down into the threads and helps with the release. I've used a crowfoot wrench to remove the sensor before, but I think the socket with a slot would give a better grip. I wouldn't cut the capillary tube until I had exhausted every other avenue.

 

[John Turney]

Russ Thompson was able to remove it using a deep impact socket with slot

Where in the world is Russ I have not seen him since the Austin Healey store folded in Sanfernado Valley???

He was in Monterey for Healey Week.

 

[Randy Forbes]

If it's been Loctited (talk about DPOs!) you'll need to release the Loctite first by heating the area in the cylinder head first. I'd probably use a torch with Mapp gas. While it's still hot you might try holding a candle to the threads of the sensor so the wax seeps down into the threads and helps with the release. I've used a crowfoot wrench to remove the sensor before, but I think the socket with a slot would give a better grip. I wouldn't cut the capillary tube until I had exhausted every other avenue.

I could not have made a better recommendation! I do however, have two (2) complete sets, SAE & Metric of crow's foot wrenches that I never reach for__I've yet to exhaust all possibilities before needing them.

 

[Bob_Spidell]

Loctite???!!! I always use teflon tape on these; seals better AND comes out easier (and I like Loctite--blue, mostly).

 

[Michael Oritt]

You might get lucky using a deep socket or box wrench into which you have cut a slot but these tools were intended to be intact and there is a risk of its deforming such as happened to Steve G. and rounding off the nut. Better to find a purpose-designed slotted socket such as this (in, of course, the proper size):

https://mobiledistributorsupply.com...Lael6itCsGtbXfjx1IkFCBHIWc8mXROhoClRIQAvD_BwE

 

[Bob_Spidell]

Would a flare nut wrench work? IIRC, it's a 5/8" nut.

 

[steveg]

Would a flare nut wrench work? IIRC, it's a 5/8" nut.

If you ground it down to fit between the sensor and head. pretty tight there.

 

[steveg]

If it's been Loctited (talk about DPOs!) you'll need to release the Loctite first by heating the area in the cylinder head first. I'd probably use a torch with Mapp gas. While it's still hot you might try holding a candle to the threads of the sensor so the wax seeps down into the threads and helps with the release. I've used a crowfoot wrench to remove the sensor before, but I think the socket with a slot would give a better grip. I wouldn't cut the capillary tube until I had exhausted every other avenue.

IMO a crow's foot isn't going to work unless it's already so loose as to not be a problem. You have to grip it all the way around.

Agree re the capillary tube - you may get it loose without tweaking the tube. If you screw up, you're no worse off than if you cut the tube in the first place.

 

[Joe Schlosser]

There are special sockets that are made to remove the Oxygen sensors. Similar to what has been described by cutting a slot but are designed for the slot.
Oxygen sensors can be very tight due to the heat cycles they see.

 

[steveg]

There are special sockets that are made to remove the Oxygen sensors. Similar to what has been described by cutting a slot but are designed for the slot.
Oxygen sensors can be very tight due to the heat cycles they see.

O2 sensor wrenches are 7/8" / 22mm.

I was unable to find a slotted socket at all in 5/8"

 

[Roberte]

Thank you all for the replies. I will first determine if any of my existing wrenches will sufficiently grip the bolt head and, if so, use a torch to heat the nut. If they don't grip sufficiently I will then try the split socket + torch. Hopefully, due to my very limited available funds, I won't have to resort to cutting the capillary tube.

Will post the results.

Robert