O2 Sensor location BF150

[juice69]

Hey everyone. Pretty certain I have an O2 sensor going bad on my port engine. I've reviewed the repair manual, but still not certain exactly where this is located. My boat is dry stored at the marina so it's a bit difficult go there just to have look at it and see what's involved with replacing this. I pulled a stock photo from Honda, and assuming this is it - where I circled?? Also, is this the only one to replace? And many thanks to everyone

 

[jgmo]

Hi,

I haven't worked on one of those but I'm pretty sure that you have it correctly identified.

As further reference, look at item 15 in the parts link. Upper starboard side and toward the rear of the powerhead.

While not completely clear, the electrical connector looks right to me too. And, yes, there's only one listed. $271.76.

https://www.boats.net/catalog/honda/outboard/2007-and-later/40hp/bf40dk2-lrta-vin-bbdj-1100001-to-bbdj-1199999/cylinder-block

You may find, that to remove and install, a special 6 point socket is needed. It has a slot that accepts the wiring pigtail in order to allow it to rotate with the sensor.

Those sockets can often be purchased at tool outlets like Harbor Freight after measuring the hex portion.

First though you might check with parts stores like Auto Zone or O'Reilly's to see if they will loan you one.

The sensors can be easily damaged if handled improperly. so use caution.

If at all possible, torque according to specifications. The torque wrench might be a loaner item too.

Good luck.

 

[jgmo]

Apologies....
I posted the wrong parts page.

Here's the one I should have referenced....

https://www.boats.net/catalog/honda/outboard/2007-and-later/150hp/bf150d-lra-vin-bbuj-1000001-and-up/exhaust-pipe

As you can see, the location does seem to correspond to your photo and there is only 1 sensor listed albeit for a few dollars more.

Sorry about that. I wasn't trying to confuse the issue and hope I didn't.

Good luck

 

[HonDan]

Yes the Air fuel ratio sensor (o2), it's the stainless-steel sparkplug looking thing on the top of the exhaust manifold with a blue wire on it. You'll need the long socket with slit type 7/8-22mm O2 sensor tool to remove it. The OEM Denso replacement is spendy, I have replaced with long term success using compatible Walker brand 02 sensor for $100 less.
Torque spec Sec 2-7 page18 shop manual says 31lbs so you will likely need a long-handled socket wrench or breaker bar to get old one out.
Page 5-154 A/F removal reinstall shows a different lower torque value, so I go little lighter than 31lbs when putting them back in.

 

[juice69]

Thanks to both. I ordered and will hopefully receive before this weekend. And thanks for the advice and details on the special socket.

 

[iang6766]

I just de pin the 4 pin plug and use a 22mm ring spanner.