garfieldthecat
SILVER Star
Hello fellow MUDders, I am putting together a 2F for my 60 with scraped up parts and have a question about the 2F intake manifold's taper screw plug, pictured here:
A previous owner of the intake manifold I have crossthreaded the hole the taper screw plug goes into and I want to chase the threads with a thread chaser since the plug will only go in about halfway now.
I was wondering if anyone knew if this screw plug was BPST or NPT and its threads per inch? I measured with the caliper and it looks like its 41/64" in diameter:
The threads did not match either the 1.25 metric or the 18 or 20 SAE threads on my thread gauge, and I don't have a BSPT/NPT thread gauge to confirm if the taper plug screw's tpi might be within either of those standards. It looks like BSPT has a 19 tpi standard but then it also comes in 1/4" per foot taper and 3/4" per foot taper and I wouldnt know how to determine the per foot taper of this taper screw plug.
Here is how the plug measures against 18 tpi on the SAE thread gauge leaf:
And here is a photo of the crossthreads some other bonehead besides myself put into the intake that won't allow the plug to screw in but half-way:
If anyone could help me with information about what this taper screw plug and hole's size is so I can chase the thread appropriately, I would be so grateful and willing to pay the customary MUD fee of beers. I am hesitant to continue putting more parts on the engine until I address this as I don't want to end up having to disassemble it to take the manifolds back to the machine shop.
Also, if anyone may know what the best thread sealer to use on this application might be, that would be awesome if shared with me as well. I imagine the intake has to have a good vacuum and thus all ports that should be sealed should seal airtight.
Thanks to all who take a moment to share their thoughts and wisdom.
Here is the engine in progress:
A previous owner of the intake manifold I have crossthreaded the hole the taper screw plug goes into and I want to chase the threads with a thread chaser since the plug will only go in about halfway now.
I was wondering if anyone knew if this screw plug was BPST or NPT and its threads per inch? I measured with the caliper and it looks like its 41/64" in diameter:
The threads did not match either the 1.25 metric or the 18 or 20 SAE threads on my thread gauge, and I don't have a BSPT/NPT thread gauge to confirm if the taper plug screw's tpi might be within either of those standards. It looks like BSPT has a 19 tpi standard but then it also comes in 1/4" per foot taper and 3/4" per foot taper and I wouldnt know how to determine the per foot taper of this taper screw plug.
Here is how the plug measures against 18 tpi on the SAE thread gauge leaf:
And here is a photo of the crossthreads some other bonehead besides myself put into the intake that won't allow the plug to screw in but half-way:
If anyone could help me with information about what this taper screw plug and hole's size is so I can chase the thread appropriately, I would be so grateful and willing to pay the customary MUD fee of beers. I am hesitant to continue putting more parts on the engine until I address this as I don't want to end up having to disassemble it to take the manifolds back to the machine shop.
Also, if anyone may know what the best thread sealer to use on this application might be, that would be awesome if shared with me as well. I imagine the intake has to have a good vacuum and thus all ports that should be sealed should seal airtight.
Thanks to all who take a moment to share their thoughts and wisdom.
Here is the engine in progress: