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Bugeye Radiator Tank Plug Size?
- Thread starter samjones
- Start date
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Joe Schlosser
Jedi Warrior
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Are you asking about the bung for the temperature sending unit??
Trevor Jessie
Yoda
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Isnt pipe thread named by the pipe size and not the fitting? I was thinking 3/8 parallel British pipe thread...19tpi
BlueMax
Jedi Warrior
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When I had my Serck made I was fortunate to speak with the production manage, Roy at the time, being gun shy with Ron Davis and Griffin. Roy and I were discussing their services regarding the MK1 radiator being that I wanted mine engineered a little differently than the standard MK1 especially the tank bung as electric cooling puller fan. I asked Roy what size it was; he quickly said with his heavy British accent that it was ½ BSP. I never worried about having any issues as Roy explained that they even build most of the F1 radiators for the F1 teams. My bung was made for a 19mm x 1.5 for the fan switch.
Trevor Jessie
Yoda
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well, if a dude with a British accent told you that was the size then that is probably all the info Sam needs.
Trevor Jessie
Yoda
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I went to the parts spare parts bin. It is definitely bigger than 3/8 bspp. So likelyit is 1/2 inch. Ill get mythread gauges and check this evening
Trevor Jessie
Yoda
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I've had some experience reading a thread gauge. Turns out my first inclination was correct. It is 3/8 bspp.
Joe Schlosser
Jedi Warrior
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Remember that nominal pipe sizes , both US and British, do not match the actual size of the fitting. The Nominal is always smaller than the actual size of the fitting. the nominal size is related to the internal size of the pipe that is being used.
A 1/8 inch NPT is closer to 1/4 inch OD but the pipe id is closer to 1/8.
Also, I understand that BSP stands for British Straight Pipe, as opposed to a tapered fitting as in NPT, National Pipe tapered
A 1/8 inch NPT is closer to 1/4 inch OD but the pipe id is closer to 1/8.
Also, I understand that BSP stands for British Straight Pipe, as opposed to a tapered fitting as in NPT, National Pipe tapered
Trevor Jessie
Yoda
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BlueMax
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Knowing that none of the above including my self are not in the heat exchanger business. For the benefit of all, I contacted Serck MotorSport who is a division of Unipart Group of Companies Ltd UK. Unipart is OEM who purchase BMC who made the Bugeye/Frogeye. Sereck Motorsport manufactures a aluminum performance radiator for the original replacement . In conversation with Roy Ripley who is production manger, stated that they have to machine each temperature bung before its welded into the tank. I have attached his reply to confirm for everyone of what size it's machined.
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Trevor Jessie
Yoda
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OK, so you are telling me that the threads (major diameter) on your temp sender are .825 inches?
All mine are .656 inches.
.825 inches is the major diameter of 1/2" BSPP fitting
.656 inches is the major diameter of 3/8" BSPP fitting
This information is out of a Parker handbook and I verified it with several web sources. I made measurements with a caliper and thread gauge. Is it possible that your supplier simply misspoke or they use their own "nomenclature" in their shop?
As far as I'm concerned the issue is resolved: The threads are 3/8" BSPP. It is helpful to note the seat in the connector.
All mine are .656 inches.
.825 inches is the major diameter of 1/2" BSPP fitting
.656 inches is the major diameter of 3/8" BSPP fitting
This information is out of a Parker handbook and I verified it with several web sources. I made measurements with a caliper and thread gauge. Is it possible that your supplier simply misspoke or they use their own "nomenclature" in their shop?
As far as I'm concerned the issue is resolved: The threads are 3/8" BSPP. It is helpful to note the seat in the connector.
BlueMax
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As far as Serck comments, Roy stated all the custom radiators they offer in their performance products they keep an original radiator for each car in stock instead of having engineered drawings to work from. They reverse engineer to fabrication to prevent mistakes he said. Like in my situation with core shift forward and electric fan brackets to accommodate the 11” Spal fan with custom bung dimension. So they keep the genuine part for standard replacement, but also can make the changes to customers request without issues of fitment.
My Bugeye was manufactured in Oct of 1959. I’m the second owner of this car. I still have the original radiator. To add coal to the fire my OEM radiator bung measures .562 ID.
My radiator is still good, wanted a little better cooling with an electric fan and less drag for the 1380 to have to pull. I can’t qualify what is and isn’t all I can say and contribute is what Serck says and what my car had when it came from the factory.
As far as the issue being resolved the 3/8 BSP doesn’t hold water for my original radiator size nor, does it hold water for the Serck.
My Bugeye was manufactured in Oct of 1959. I’m the second owner of this car. I still have the original radiator. To add coal to the fire my OEM radiator bung measures .562 ID.
My radiator is still good, wanted a little better cooling with an electric fan and less drag for the 1380 to have to pull. I can’t qualify what is and isn’t all I can say and contribute is what Serck says and what my car had when it came from the factory.
As far as the issue being resolved the 3/8 BSP doesn’t hold water for my original radiator size nor, does it hold water for the Serck.
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Trevor Jessie
Yoda
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At least when someone finds this thread at a latter date they will know to verify.
If your OEM radiator bung has an inner diameter is 0.562, then it is clearly NOT 1/2" BSPP as Serck described it. In fact, the minor thread diameter for 3/8" BSPP is 0.589 inches, so you are likely have a slight measuring error. Your measurement verifies that the thread is likely 3/8" BSPP.
If your OEM radiator bung has an inner diameter is 0.562, then it is clearly NOT 1/2" BSPP as Serck described it. In fact, the minor thread diameter for 3/8" BSPP is 0.589 inches, so you are likely have a slight measuring error. Your measurement verifies that the thread is likely 3/8" BSPP.
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BlueMax
Jedi Warrior
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The bung on my original radiator has a recess that is machined about a 1/2 mm down before the threads start. At the very opening its .589/.590 but where the actual threads are .562.
If you’re questioning Serck MorterSport authority, then I suggest you contact Roy at SerckMotor Sport to discuss the issue? For they ship these radiators all over the world.
If you’re questioning Serck MorterSport authority, then I suggest you contact Roy at SerckMotor Sport to discuss the issue? For they ship these radiators all over the world.
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Trevor Jessie
Yoda
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I'm not saying that they are made wrong. I'm saying they told you the wrong size of the bung. Your measurements are consistent with 3/8" BSPP. If your OEM style temperature gauge fits in the radiator they made for you, then the threads are likely 3/8" BSPP.
Trevor Jessie
Yoda
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Rut, it is 19tpi. And 18tpi gauge almost fits because of the different angle. Try a 19 tpi and see if it fits better.