2005 DF140 issues

[redlowrey]

The temp sensor does not ground through the cyl head, it should have nothing to do with the charging system. the computer sends out 5 volts it goes through the sensor and grounds internally pin 11 sensor ground with other sensors. your temp sensor would still work even if was suspended in mid air it just would not reflect the the true voltage being sent to the computer.
What I mean is as the temperature of the engine increases the resistance of the sensor decreases, so being screwed into the head all that heat will go into the sensor dropping the voltage below 1 volt at operating temp.

So probably before with the sensor just sitting in the hole and the thermostat stuck open the voltage going to the computer would have been over 1 volt. All that means the engine would be running richer than it is.

[slayray]

Hey Red is there any reason why it seems like my charging issue has been fixed? My chart plotter now says it’s charging almost continuously at 13.8-14.1 volts I’ve never seen that before it was always 12.8 charging then batteries would isolate immediately. All I’ve done is install temp sensor and replaced thermostat that was stuck open

[slayray]

Im gonna give it a whirl! I looked up a bunch of forums about it but never did get it to work. Leaves me thinking its broken somewhere under the deck.

Also thank you Red for all the help. I was able to see my thermostat wasnt functioning correctly and was stuck open.

[Moonlighter]

Can only reset oil change via the kill switch. Not via SDS. Suggest that you’ll need to fix that wiring…

[slayray]

If you got it to screw in a few turns and it is tight leave it, if your thermostat is working correctly it will come down below 1 volt at operating temp.

Thanks for all the help red. I hooked it up to SDS and could only see temperature not voltage. Do you know how I can access the voltage? I did see my engine was hovering at 107 degrees after 15 mins so I pulled the thermostat and it was stuck open.

Also is there anyway to reset the oil change alarm on SDS instead of the kill switch? Kill switch itself works but not sure why it doesnt kill the motor. I think broken wire in harness.

[redlowrey]

If you got it to screw in a few turns and it is tight leave it, if your thermostat is working correctly it will come down below 1 volt at operating temp.

[slayray]

Well bad news. I tried to use a tap but it kept going in crooked. My sensor gets tight pretty quick and have about an 1/8 inch sticking up before being fully seated. What are your thoughts on drilling a bigger hole and doing a thread insert? I would think that would screw up the surface contacting the top smooth part of the sensor. Unfortunately it does not seat nicely like I would have liked it too.

Anyway I could run SDS and see if it’s acting correctly? I’m bummed I wasn’t able to get it to seat flush.

[redlowrey]

If you think there is enough to take out without hitting the thread go for it, you might be able to go from an imperial drill bit to metric EG, 3\ 8 is 375 thou 10 mill is 400 thou, 25 thou difference in diameter, 5\16 is 312 thou 8 mill 320 thou, if you get the drift.
I don't have an old sensor laying around so I don't know if they are a gas thread or a fine metric thread, if it is gas I could be NPT, or bsp, try to use an intermediate tap first it will have enough taper on to get started then your plug tap.
It is a very important sensor and it needs to be screwed neatly into the head to transfer the heat into the sensor to change the resistance accurately.

[slayray]

Okay Red, just like you said it started crumbling. I got multiple size extractors in with no luck the metal was too maleable. The good thing is i got a good center for the drilling. I am currently using a 1/4 bit and feel like thats as large as I can go before the threads start being affected. I was able to get about 1/2 the diameter for the first thread out but the thread doesnt look clean and distinguishable. Underneath it looked like salt in the thread groove. I am using a small pick to run through the thread but its just not strong enough.

Should I go up in diameter bit? Or start a tap?

I can see the finish line I just don't wanna screw it up.
Thanks again for all your help.

[redlowrey]

I can see it now, measure to see how much you have got to play with, let it soak for a week. The only trouble drilling and tapping if you don't get the center punch central you will drill off into the thread.
I think the inside of the sensor might crumble as you extract, see how you go if it crumbles just use a bigger drill and keep going to the wall trying not to damage the thread.

[slayray]

I can't up load the picture, I would try and get it out with an easy out the only downside is as you screw the extractor in it will tend to spread the case of the sensor in to the thread.
I would try that first and I would soak the hole with penatriene for a week first, some of it might get down past the threads.

Hey Red, I updated the permissions to the picture. Okay if I try the extraction method and it doesn’t work what then would you do? Drill and retap?

[redlowrey]

I can't up load the picture, I would try and get it out with an easy out the only downside is as you screw the extractor in it will tend to spread the case of the sensor in to the thread.
I would try that first and I would soak the hole with penatriene for a week first, some of it might get down past the threads.

[slayray]

https://drive.google.com/file/d/15Ql...w?usp=drivesdk

here is a picture of the broken off threads of the sensor. Looks like a new sensor was already bought but never installed due to broken threads. The first half of the hole is smooth which matches up with the smooth part of the sensor then a hard stop where threads line up.

would you recommend doing a center punch, drill, and bolt extractor? I don’t wanna hit the water jacket like you said Red.

[redlowrey]

Be careful if you have the late type of sensor it screws into a blind hole, and you might drill into the water jacket.
Did all the threaded part of the sensor come out, Buy a new sensor and you will be able to determine how much is still in the head.
You will be able to see how far you can drill with out causing a problem.

[slayray]

What Murray means is with the engine running, the most important thing to do is clean the throttle body housing and throttle plate especially the under side of the plate and pull the temp sensor out and have a look to see if the sensor housing goes through to the water jacket or bottoms out.

Early systems went through to water late systems bottomed out, very important sensor, it needs to be screwed in firm to be able change in resistance to the changing water temp.

You should be able to watch your sds for the closed throttle switch, when you open and close the throttle it will tell you off or on.

Hey Red. Unfortunately my temp sensor is snapped off looks like the bottom part of the sensor is stuck in the hole. Should I drill out and retap? Whats the process you would you use? Thanks