V8 Rocker cover ht lead clip thread size

V8 Rocker cover ht lead clip thread size

Author
Discussion

blaze_away

Original Poster:

1,555 posts

220 months

Sunday 11th November 2018
quotequote all
On the rover v8 (chim griff etc) there are holes in the top to hold ht lead retaining clips.

Anyone know what thread size they are
Fyi they are bigger than 4mm and smaller than 5mm.

I suspect they are imperial 3/16 unf but just guessing.

Why do I ask. I want to tidy up my ht leads using some chromed clips I have so what to buy some suitable set screws to hold them in place.

phillpot

17,279 posts

190 months

Sunday 11th November 2018
quotequote all


Self tappers on mine.................


Classic Chim

12,424 posts

156 months

Sunday 11th November 2018
quotequote all
Sounds about right, car is metric mostly, engine UNF as it’s so old wink

phillpot

17,279 posts

190 months

Sunday 11th November 2018
quotequote all
Classic Chim said:
engine UNF as it’s so old wink
and originates from America wink

blaze_away

Original Poster:

1,555 posts

220 months

Sunday 11th November 2018
quotequote all
Thanks fellas unfortunately self tapers wont work with the clips I have as they are two piece and defo need nuts and bolts to hold them together.

So, still really need to find what threads are.

fausTVR

1,442 posts

157 months

Sunday 11th November 2018
quotequote all
I've just seen my TVR for the 1st time since the summer 2017 (wow pretty!), unscrewed that bolt, it does look like the one pictured above.
Measures 3/16" (4.76mm) dia with what looks to be a 1/16" pitch thread, didn't manage to identify what that equates to though. Does look like a self tapper.

bobfather

11,187 posts

262 months

Sunday 11th November 2018
quotequote all
blaze_away said:
Thanks fellas unfortunately self tapers wont work with the clips I have as they are two piece and defo need nuts and bolts to hold them together.

So, still really need to find what threads are.
The two piece HT lead clips are intended to be used as additions to the fixed clips. They should be placed along the HT leads to maintain separation


Steve_D

13,796 posts

265 months

Sunday 11th November 2018
quotequote all
As said they are self tappers so no thread in the hole until you put a self tapping screw in.

If you want to put something different in there then you will need to drill and tap. However if you do you will need to drill right through as it is almost impossible to tap a shallow blind hole.

Steve

blaze_away

Original Poster:

1,555 posts

220 months

Sunday 11th November 2018
quotequote all
Interesting. Mine have threads. Will take a closer look tomorrow in daylight.

ianwayne

6,612 posts

275 months

Monday 12th November 2018
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I think there's a reason for the rocker covers not having the holes threaded. Currently, a self-tapper clamps the plastic HT lead retainers down (on mine) but they can still twist and move slightly, allowing for flexing in the HT cables.

If the holes were threaded, you'd either have to tighten right down so that the lead retainers were clamped stationary or leave the bolt / screw loose in which case the vibration would undo it. This would be OK on the o/s rocker cover where the clamp sits in the fins in the cover, but not on the n/s.

Steve_D

13,796 posts

265 months

Monday 12th November 2018
quotequote all
blaze_away said:
Interesting. Mine have threads. Will take a closer look tomorrow in daylight.
Perhaps they appear to have threads but you are just seeing the 'thread' cut by the self tapper.

Steve

Dougie Jim

1 posts

53 months

Thursday 18th June 2020
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I’ve been looking for the answer to this question for my MGB V8. Hence finding this forum.

By trial and error I have now found the right size for the MGB V8. The thread for these is 3/8 UNC or 10 - 24, it therefore would make sense that this would be the case in other applications?

Hopefully this will assist someone.

Steve_D

13,796 posts

265 months

Friday 19th June 2020
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Whilst those thread sizes may seem to fit I can assure you the screw used by Rover is a self tapper.

Here's one I removed a few minutes ago.



Steve

phillpot

17,279 posts

190 months

Friday 19th June 2020
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Dougie Jim said:
The thread for these is 3/8 UNC or 10 - 24
Are you sure?
Seems a little ott for a lead clip.......scratchchin