'38 V8-60 leaky temp sender at block

jim galli

jim galli

Senior Member
tempSender.jpg

What am I missing. The nut goes all the way into the head and it's still loose. You can pull it in and out, and it dribbles coolant all the time. Thanks! Head, not block. Doh!
 
If the head is original to 38 and in good shape, the thread should be 5/8-18 straight thread to match the temperature probe nut thread. Sometimes the last few threads in the head prevent the nut from actually tightening down correctly. This can be cured by using a "No Bottom" tap and cleaning out the bottom threads. If the cast iron seat for the temperature bulb is cracked or rusted this could also allow coolant to seep past the seat. If there is no seat it may be possible someone enlarged the hole and may have made it 1/4-18 NPT tapered pipe thread in this case the adapter is necessary. I believe NAPA and Speedway both sell the adapter.
 
I suspect you have an incorrect head. Just the fact that it is steel tells me that's most likely the case. Even Ford heads, made for servicing did not have the requisite seat at the bottom of the threaded port. With a proper head the sending unit would bottom out and subsequently seal. With an incorrect head you will need an adapter as Terry advised.
 
I believe the engine was replaced in the early '60's with a 1940 unit. The head is cast iron. Anyone got a part number for the adapter? Thanks.
 
You must log in or register to reply here.
Back
Top