aftermarket temp sensor
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On The Tree
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aftermarket temp sensor ive bought me an after market water temp guage but i dont know where to put it, the sensor is too big to fit the head and its not a metric thread, is there one that i can buy that will fit the head?
I am using an AutoMeter electric temperature gauge. One head will have the temperature sending unit for the ECM and the other head will have a plug in the same position. I took the plug out and drilled/tapped the hole for the NPT thread that my AutoMeter sending unit needed. I can't remember if it was 1/8" or 1/4" NPT. If you already have the drill bit and tap this is a freebie - and that doesn't happen very often.
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I had the same issue and don't have the tools or workspace to guarantee super-straight drilling so just did this (scroll down a bit): https://ls1tech.com/forums/14117849-post31.html
Depends on your setup, but having never drilled and tapped anything before I wanted to start with something a bit more disposable than a head. In hindsight it's pretty simple though.
Depends on your setup, but having never drilled and tapped anything before I wanted to start with something a bit more disposable than a head. In hindsight it's pretty simple though.
This is what I was thinking. If your sensor is 1/8 NPT then you're set. If your sensor is 1/4 NPT, Parker stores should stock (and in the worst case can order) the fitting you need in steel. It's M12x1.5 male to 1/4 NPT female.
The M12x1.5 to 1/8 NPT adapter linked above has a rep for stripping out cause it is so thin. I have never seen an M12x1.5 to 1/4 NPT. It would be hard to imagine how that is possible.
Most temp sensors are 3/8 or even 1/2 NPT. Another option is there is a member on here who turns down the 3/8 NPT sensors to fit the metric thread.
Most temp sensors are 3/8 or even 1/2 NPT. Another option is there is a member on here who turns down the 3/8 NPT sensors to fit the metric thread.
I prefer the steel fittings over the brass fittings any day... much less chance of it stripping. You can tighten the NPT sides tighter with more confidence. Check out this site for steel M12x1.5 male to both 1/8, 1/4 and 3/8 NPT female:
http://www.discounthydraulichose.com...ale_p/9235.htm
Note it says "NPTF" - this has a better thread fit than regular NPT... I can't remember the specifics, but it's compatible with regular NPT.
http://www.discounthydraulichose.com...ale_p/9235.htm
Note it says "NPTF" - this has a better thread fit than regular NPT... I can't remember the specifics, but it's compatible with regular NPT.
The M12x1.5 to 1/8 NPT adapter linked above has a rep for stripping out cause it is so thin. I have never seen an M12x1.5 to 1/4 NPT. It would be hard to imagine how that is possible.
Most temp sensors are 3/8 or even 1/2 NPT. Another option is there is a member on here who turns down the 3/8 NPT sensors to fit the metric thread.
Most temp sensors are 3/8 or even 1/2 NPT. Another option is there is a member on here who turns down the 3/8 NPT sensors to fit the metric thread.
Interesting link. I see how that is possible. Those hydraulic adapters place the larger diameter fitting completely outside the head. They also don't seem to have much depth to accomodate a temp probe, especially the one Toughy v8 posted.
Even if it fit it would be interesting to see what using something like that does to the accuracy of the temp reading.
Even if it fit it would be interesting to see what using something like that does to the accuracy of the temp reading.
Sreet & Performance S&P makes an adaptor for what you are trying to do, you remove the hex plug on the rear of the passenger head (this is the plug where the stock temperature sensor would go if the head were mounted on the drivers side) and install their adaptor which is the correct metric male size for the head side and then on the female side for the sending unit they come in various sizes 1/8 1/4 and 1/2 (your choice when ordering) to accomodate the sending units long probe, it looks decent once installed and is around $20 if I remember right, and the best part it is completely reversible procedure that lets you go back to stock and it requires no drilling or tapping for those with limited skills and tools.
Last edited by lizeec; Nov 16, 2010 at 06:55 PM.
I used the autometer adapter and autometer electric temp sender. I had to drill out the adapter so the electric sender would fit through the smooth part of the hole in the adapter, but other than that it works great.
Yea, it's not really ideal for a temp sensor. I would probably not use it on a sensor that sent its reading to the PCM, but for a temp gauge, I would consider it.
Pressure senders, on the other hand, should not be affected by the depth of the fitting. I am thinking about putting my oil pressure sending unit down in the oil block-off plate on the oil pan. My block-off plate is from a Corvette, and OEM-threaded for a 12x1.5 oil temp sender. (which I think is the same part as the water temp sender)
Pressure senders, on the other hand, should not be affected by the depth of the fitting. I am thinking about putting my oil pressure sending unit down in the oil block-off plate on the oil pan. My block-off plate is from a Corvette, and OEM-threaded for a 12x1.5 oil temp sender. (which I think is the same part as the water temp sender)
Interesting link. I see how that is possible. Those hydraulic adapters place the larger diameter fitting completely outside the head. They also don't seem to have much depth to accomodate a temp probe, especially the one Toughy v8 posted.
Even if it fit it would be interesting to see what using something like that does to the accuracy of the temp reading.
Even if it fit it would be interesting to see what using something like that does to the accuracy of the temp reading.
On The Tree
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i know this is an old thread, but i'm going through this process right now. I have the long sensor that came with my autometer gauge, and i'm ordering the short one that fits inside their M12 to 1/8 adapter. Some people have been getting low readings on their gauges, and i'm not sure why. I have two ideas, one people are using too much teflon tape and making the resistance to ground too high. the other has to do with the sensor probe not sticking into the head far enough when people drill and tap the head to use one of the larger standard thread fittings.
i've ordered a M12 to 1/8 adapter for the long sender. I'm going to compare the wall thickness to the adapter autometer sells to go with the short sender. I definitely dont want the bolt to snap inside the head. I hope the low readings people are getting is just due to using too much tape/thread sealant.
does anyone else have a definitive answer on this issue?
i've ordered a M12 to 1/8 adapter for the long sender. I'm going to compare the wall thickness to the adapter autometer sells to go with the short sender. I definitely dont want the bolt to snap inside the head. I hope the low readings people are getting is just due to using too much tape/thread sealant.
does anyone else have a definitive answer on this issue?
I really doubt this is an issue. I've used teflon tape on NPT fittings and then taken them apart, only to find that the edge of the thread cut through the teflon tape. If the length of the thread is cutting through the tape and contacting the body of the other fitting, there should be plenty of contact area for a good connection. Resistance should be negligible... I couldn't see the limited contact area adding even a full ohm of resistance.
I was thinking the same thing you were before seeing the threads cut through the tape. If you go to Stewart-Warner's website, the recommend NOT using any type of sealing liquid or tape on their senders.
I am using teflon tape on both my oil pressure gauge sender (Stewart-Warner) and oil pressure idiot light switch. Both of these seem to work fine with teflon tape in place. I have NOT tried using the liquid teflon sealant.
I was thinking the same thing you were before seeing the threads cut through the tape. If you go to Stewart-Warner's website, the recommend NOT using any type of sealing liquid or tape on their senders.
I am using teflon tape on both my oil pressure gauge sender (Stewart-Warner) and oil pressure idiot light switch. Both of these seem to work fine with teflon tape in place. I have NOT tried using the liquid teflon sealant.
I wondered about sealant affecting the electrical connection also. Even went so far as looking for conductive paste of some type, maybe a copper based gel.
But in the end I just put everything together with liquid Teflon and didn’t have an issue.
If you think your sensor is inaccurate, disconnect it from the engine and put it in a pot of boiling water with a kitchen thermometer.
But in the end I just put everything together with liquid Teflon and didn’t have an issue.
If you think your sensor is inaccurate, disconnect it from the engine and put it in a pot of boiling water with a kitchen thermometer.