Jeep 3.7L Crank Sensor removal

[3930dave]

More than a few folks have had grief with these, so I thought I'd post what worked for me today.

Once the one bolt is out of this crank sensor, you are left to deal with the corrosion keeping this press-in, O-ring sealed sensor locked into it's bore. It is a plastic bodied sensor, and just a bit of surfing will show many people who have broken these off flush with the block - most of the time these won't stand up to much in the way of twisting or prying.

I used Deep Creep to soak the sensor with - next time I'll start at soaking at least 24 hours ahead of time. It finally did work, but I needed patience today....

On the '05 Jeep I was working on, the crank sensor has a raised boss that the mounting bolt goes into. I looped a 50# rated tie-wrap through the gap under the metal tab on the sensor, and used that to pull with one hand, at the same time I rocked/pulled the sensor with my other hand.

After a few soak/rock/pull sessions, it finally became unfrozen - at that point I was looking at the still intact 50# tie-wrap all by itself in one hand. For one second I wasn't sure if the sensor body had broken - Murphy gave me a free pass on this one today - I was able to get it out intact.

No guarantees that Tie Wrap aided pulling will work every time, but given how many folks have broken these, I'm going to keep this in mind for my next sensor "challenge"...... for something that installs easy at the factory, you need very little corrosion in place to make it a difficult pull.

Rgds, D.

 

[KyleH]

Good tip and thanks for sharing,

You can also put some heat to the block around the sensor or even the sensor itself if it breaks apart and pull it out with a pick when it starts to melt a bit. Just be sure to clean any rust out of the hole before trying to pull it out. Changed tons of these over the years working for a Chrysler dealership in the past. The 3.7L and 4.7L are the same design for anybody that has a truck or grand Cherokee. The 5.7L is a different engine design but same type of sensor and can removed in the same manner.

 

[3930dave]

Good tip and thanks for sharing,

You can also put some heat to the block around the sensor or even the sensor itself if it breaks apart and pull it out with a pick when it starts to melt a bit. Just be sure to clean any rust out of the hole before trying to pull it out. Changed tons of these over the years working for a Chrysler dealership in the past. The 3.7L and 4.7L are the same design for anybody that has a truck or grand Cherokee. The 5.7L is a different engine design but same type of sensor and can removed in the same manner.

With more practice, I'd trying throwing heat at it like you describe - that would be the fast way to clear a hoist :thumbsup:

This was the first one of these I've had to do.... to say that I was concerned about losing pieces into the oil pan is an understatement !

Rgds, D.

 

[KyleH]

Had a customer do just that once, then tried to remove the oil pan to get it. Not a fun job and requires lowering the front diff to get the pan out. Sometimes it's cheaper to pay a mechanic at the dealership, but can't blame people for trying to save some money doing things themselves.