Dea_944t

The manufacturer of my new oil temp gauge recommends teflon tape on the sensor.
I normally try to avoid this and since the sensor will be in the oil drain plug where there's no pressure and it's a 1/8 NPT thread I was hoping it might not be needed.

Any experiences of this?

/Dea

Techno Duck

Teflon tape it, or better yet use a good oil resistant thread sealant.

I neglected to do so and it was a total mess during that oil change interval .

BTW, national pipe thread is not leak free on its own. You must use a thread sealant with it.

Dea_944t

Thanks!

Any ideas on good sealants? I always worry that the sealant will dissolve and clog someting up...... maybe I should use the teflon tape, it's at least oil resistant.

The one I have is only 0,075 mm maybe I should get a thicker one, 0,1 or 0,2 mm.

/Dea

KSira

Had the same question while installing my oil temp sensor, but the experts in the shop told me Teflon tape was the best solution. Has held up fine a few months no, but no long term experience yet

GreyDog

Somewhat related, should one use any sort of tape on fuel fittings or will it dissolve?

xupkid2

Go to your local autozone and they have a hi temp thread sealant that Permatex makes. Its a little white tube and only costs a few bucks. I have used it in many places on my race car based on Techno Duck's turbo install write up and had great no issues.

Techno Duck

This is the stuff i have used for oil related fittings. Just make sure you let it cure for however long the directions say. Personally i would always use this over teflon tape. I never had much luck getting the oil drain plug sensor on my n/a to stop leaking after a few thousand miles (it made a mess of the driveway during that oil change interval). Also teflon was no match for sealing the oil fitting on my turbo.



Also most fuel fittings are mechanical seal, no sealant is needed.

fortysixandtwo

The Permatex product shown above is the only thing I use to seal pipe threads on my vehicles.
In general, paste type thread sealants are the only way to go. After trying to use teflon tape on low pressure (450psi) helium lines and using a helium sniffer to check for leaks, I realized how horrible of a job it does a sealing. Using a paste style thread sealant produced a consistent leak free joint on 1/8" to 2" pipe joints. I ran into the same problem when pulling piping systems into deep vacuum (~50 microns).

GreyDog

Cool, thanks !

Dea_944t

I'm convinced, just need to find it. Over here Loctite is more common than Permatex.

/Dea

DLS

Även scantech o loctite har bra gängtätningar för hydraul bruk, kör själv med loctite på det mesta

Darkstar1

^^^^^ What he said!^^^^^

Duke

I use Loctite 561 stick on all almost all fluid connectors. Never had a leak with it and I prefer it over Teflon tape.

fortysixandtwo

The Henkel Loctite products work just as well, it was what I used on the helium and vacuum systems. I use the Permatex product on my vehicles because it is regularly available.

Also, for application of paste sealants, do not add the sealant to the first two full threads. This will minimize the amount of product that could be introduced into the system you're trying to seal. Most are anaerobic (cure in the absence of air) and will be fully cured at its leading edge, when applied a couple of threads back.

Dea_944t

Great! Stick is much more convenient to use as well.
Only downside with 561 seems to be the max working temp of 150C but if the oil reaches that temp in the sump I'll probably have other bigger problems....

/Dea