Temperature Sender -- No Nut?

rwmann · Post by **rwmann** » Sat Jul 18, 2020 11:27 am

Went to replace the INOP temperature sender on the 1968 U20 to find no nut securing it to the housing. There appears to be a reddish-brown sealant flush with the rear-facing machined surface of the housing that is threaded to accept the collar nut that I expected to find. What am I missing here? TIA

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Post by **spl310** » Sat Jul 18, 2020 12:47 pm

I bet that the hex sheared off the nut

rwmann · Post by **rwmann** » Sat Jul 18, 2020 1:19 pm

So you think the threaded portion of the collar is retaining the sender?

Post by **spl310** » Sat Jul 18, 2020 1:26 pm

I have seen that in the past. I would use a dental pick to gouge out the RTV that is there (the orange stuff) and see. If it is, you are in for a fun afternoon of drilling and dremel work...

rwmann · Post by **rwmann** » Sat Jul 18, 2020 2:40 pm

Structural RTV, as it turns out. No threaded collar, just a plug of RTV. Since before 1975, when it was new to me. Now I will need the gasket I don't have... Thanks for the troubleshooting suggestions, spl310!

david premo · Post by **david premo** » Sat Jul 18, 2020 5:27 pm

From the looks of it the housing broke at threads, so it would appear the PO decided to â€œglue â€œ it in.

rwmann · Post by **rwmann** » Sat Jul 18, 2020 7:47 pm

I'm surprised that RTV alone would hold cooling system pressure. For 45+ years...

Post by **spl310** » Sun Jul 19, 2020 6:22 am

Happy to help! The gasket is easy. You can make it.

JT68 · Post by **JT68** » Sun Jul 19, 2020 7:35 am

The remains of that nut are probably broken off inside.

Unless you want to spend a weekend dicking around with it, suggest you just get a new housing, sender and two new gaskets. Most vendors have them-its a much better approach overall.

rwmann · Post by **rwmann** » Sun Jul 19, 2020 3:04 pm

Internal threads were intact and held the new sender and collar nut. Fel-Pro gasket material cut to fit, fluids replaced and burped, and back in service. Thanks to the forum for assistance!

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Temperature Sender -- No Nut?

Temperature Sender -- No Nut?

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Re: Temperature Sender -- No Nut?

Re: Temperature Sender -- No Nut?

Re: Temperature Sender -- No Nut?

Re: Temperature Sender -- No Nut?

Re: Temperature Sender -- No Nut?

Re: Temperature Sender -- No Nut?

Re: Temperature Sender -- No Nut?

Re: Temperature Sender -- No Nut?