Packard Forum Index » Pre-War (1899-1942)

My 39 120 has been laying dormant for too long, waiting on the new wiring harness to be installed. One of the problems facing the reinstallation of the dash is the temperature probe. The one in the block has had the wire tube cut off by the previous owner, and I have been unable to remove the probe, despite Kroil, PB Blaster etc. I am just about to the point of sawing it off, then drilling out the portion in the block and retapping the hole to allow the installation of the correct rebuilt temp sensor. Am I asking for trouble? Anyone have any alternate solutions? thanks

David,

If it was my Packard I would consider using a little heat to free the fitting from the head. I believe the fitting is brass. Maybe a propane torch would provide enough heat to break the lock on the threads.

After market mechanical temperature gauges usually come with a variety of adapters to fit their gauges. I think the adapters have pipe thread on the part that screws into the engine block or head. The original threads for the fitting are not pipe threads.

Good luck with this.

(o[]o)

No great suggestions for success, if you drill just remember it's a tapered NPT thread so pick your drill size carefully for the minimum interior thread diameter. Drilling absolutely "on center" is important. After that, you may be able to collapse the remaining sections inward and then remove with a pin punch or similar. This method has worked for me but you need to real careful to avoid damaging the threads in the head.

PS - JW, really, they are not NPT threads? The few (various and perhaps different years) that I've worked on were. At least that's my recollection. Looks like a loose end for someone to pin down definitively.

O_D,

My comment on the threads not being NPT were based on my recall. The ones on my '37 and '47 did not look like tapered pipe threads when I had the units free from the engine. You are probably correct.

(o[]o)

I had this exact same problem on my 1955 Buick Century just this week. Like you I tried Kroil and other liquids to help free it up. But I then put the propane torch on it for a while and it finally came out.

I would try that first before drilling. What do you have to lose?

Thanks - I put the acetone/ATF solution on it tonight and will try the propane treatment tomorrow.