NPTF or BSPT ?
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I want to replace the vacuum adapter on the No1 inlet runner with a plug (servo now removed). The adapter has a tapered thread, what size do I need and is it NPTF or BSPT?
Thanks.
Thanks.
1966 Elan S3 Coupe
1994 Caterham 7
1994 Caterham 7
- englishmaninwales
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Because of the Ford link almost anything w/ pipe threads on the Kent motors have NPT. I believe the intake runner, vacuum tap follows this reasoning. Check the original Elan parts book; the code should tell you.
Roger
Roger
'67 Elan S3 SS DHC
'67 Elan FHC pre-airflow
'67 Elan S3 SE upgrade to 26R by Original owner
'58 Eleven S2 (ex-works)
'62 20/22 FJ (ex-Yamura)
'70 Elan +2S RHD
'61 20 FJ project
'76 Modus M1 F3
'67 Elan FHC pre-airflow
'67 Elan S3 SE upgrade to 26R by Original owner
'58 Eleven S2 (ex-works)
'62 20/22 FJ (ex-Yamura)
'70 Elan +2S RHD
'61 20 FJ project
'76 Modus M1 F3
- Elan45
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The ford bits have NPT threads but the Lotus bits ( e.g. head and diff housing ) have BSP threads as far as I know. Due to the small difference between the two especially in small sizes you can often satisfactorily thread an NPT fitting into the Lotus bits BSP threads
cheers
Rohan
cheers
Rohan
-
rgh0 - Coveted Fifth Gear
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Roger, is the Elan parts book a resource on this forum, or elsewhere?
1966 Elan S3 Coupe
1994 Caterham 7
1994 Caterham 7
- englishmaninwales
- Fourth Gear
- Posts: 760
- Joined: 26 Jul 2013
Thanks Rohan.
1966 Elan S3 Coupe
1994 Caterham 7
1994 Caterham 7
- englishmaninwales
- Fourth Gear
- Posts: 760
- Joined: 26 Jul 2013
On Elan the vacuum "T" adapter on the No1 inlet runner is for the servo and headlamps.
On Elan +2 it is for the headlamps only with n?4 for the servo.
I think for me it's BSP ( the head is lotus not Ford)
Alan
On Elan +2 it is for the headlamps only with n?4 for the servo.
I think for me it's BSP ( the head is lotus not Ford)
Alan
Alan.b Brittany 1972 elan sprint fhc Lagoon Blue 0460E
- alan.barker
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I fitted these:
https://www.amazon.com/gp/aw/d/B009IK28 ... ref=plSrch
1/8 ntp plugs. They seemed to fit fine and seal well enough that I believe they are correct but can't prove they aren't BSP threaded holes.
Measuring the removed factory take offs, 27tpi seems a slightly better/consistent fit than 28tpi. But again isn't conclusive.
Wide speculation but it maybe lotus went for ntp for these due to better availability of the one way valve take offs in ntp than bsp...
https://www.amazon.com/gp/aw/d/B009IK28 ... ref=plSrch
1/8 ntp plugs. They seemed to fit fine and seal well enough that I believe they are correct but can't prove they aren't BSP threaded holes.
Measuring the removed factory take offs, 27tpi seems a slightly better/consistent fit than 28tpi. But again isn't conclusive.
Wide speculation but it maybe lotus went for ntp for these due to better availability of the one way valve take offs in ntp than bsp...
'73 +2 130/5 RHD, now on the road and very slowly rolling though a "restoration"
- mbell
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englishmaninwales wrote:Roger, is the Elan parts book a resource on this forum, or elsewhere?
If you search rdent . The website there has the parts manuals and the part numbers... Somewhere on here there's a list that helps decipher the part number
1968 Elan plus 2 - project
2007 Elise S2 [modified with a Hethel 70th sticker (yellow)]
2000 Elise S1 - Sold
2007 Elise S2 [modified with a Hethel 70th sticker (yellow)]
2000 Elise S1 - Sold
- wotsisname
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There is a good parts list on this forum.
Go to the top of the page, to -WIKI COMING SOON.
Most of what you want is already there.
Eric in Burnley
1967 S3SE DHC
PS. I just tried it and it didn`t work but it is usually OK
Go to the top of the page, to -WIKI COMING SOON.
Most of what you want is already there.
Eric in Burnley
1967 S3SE DHC
PS. I just tried it and it didn`t work but it is usually OK
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Oh, it works when I do it right !!!
WIKI COMING SOON
`WIKI` on choices
`shop floor` on dropdown list
then choose `workshop manual, parts list or others.
Cheers, Eric
WIKI COMING SOON
`WIKI` on choices
`shop floor` on dropdown list
then choose `workshop manual, parts list or others.
Cheers, Eric
- ericbushby
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Well, as others have indicated, 1/8 BSPT fits fine, (although correct thread may be NPTF.)
Thanks.
Thanks.
1966 Elan S3 Coupe
1994 Caterham 7
1994 Caterham 7
- englishmaninwales
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