Bonnet striker puzzle

SD1too · 5th December 2021, 09:03

Has anybody managed to adjust their bonnet strikers ( the two spring loaded plungers screwed to the bonnet lip)?

The design hasn't changed in 50 years and I'm sure that on previous cars I simply inserted a stout screwdriver into the slot cut into the tapered end of the striker and turned it.

I'm working on someone else's 75 and even after removal to a vice, the striker shaft would not turn even by one degree! It's obviously seized with corrosion I concluded. Penetrating fluid and considerable torque failed to release it so since new ones are a reasonable price I ordered a pair. Now here's the puzzle.

These won't move either!

I just need to raise the RH side of the bonnet to be level with the wing (and yes, the rubber stop is already at full height).

Has anyone else encountered this?

Simon

rovertone · 5th December 2021, 10:17

Hi Simon,
Sorry if this is stating the obvious but you have slackened the pin lock nuts before trying to adjust via screwdriver slot?
Tony

Arctic · 5th December 2021, 10:34

Quote:

Originally Posted by rovertone

Hi Simon,
Sorry if this is stating the obvious but you have slackened the pin lock nuts before trying to adjust via screwdriver slot?
Tony

Hi Simon.
Tony as hit the nail on the head, pull the spring down a little so you can get open end spanner on the nut and undo a little, the adjust.

1

SD1too · 5th December 2021, 14:05

Quote:

Originally Posted by rovertone

Hi Simon,
Sorry if this is stating the obvious but you have slackened the pin lock nuts ...

Thanks Tony and Steve.

Is that nut really a locknut? The flanges on the plate make it extremely difficult if not impossible to rotate a 17mm spanner but also there's a sleeve on the reverse side of the plate:

Isn't that a press-fit nut designed to be held captive in the plate?
Edit: Research shows that self-clinching nuts don't have a hexagonal shape, they're round. So I'm still puzzled. What's the sleeve and why is the nut impossible to turn on a brand new part?

Simon

Typhoon190 · 5th December 2021, 16:53

Having disassembled the striker plate assembly before, the nut is there to lock the pin in position, so it will be tight but can be slackened and removed if needed.

dave lincs · 5th December 2021, 17:20

Quote:

Originally Posted by SD1too

Thanks Tony and Steve.

Is that nut really a locknut? The flanges on the plate make it extremely difficult if not impossible to rotate a 17mm spanner but also there's a sleeve on the reverse side of the plate:

Isn't that a press-fit nut designed to be held captive in the plate?
Edit: Research shows that self-clinching nuts don't have a hexagonal shape, they're round. So I'm still puzzled. What's the sleeve and why is the nut impossible to turn on a brand new part?

Simon

Hi Simon my research is as Arctic has also found the locknut is inside the spring as shown in his yet again great picture

SD1too · 5th December 2021, 18:23

Quote:

Originally Posted by Arctic

Hi Simon ... pull the spring down a little so you can get open end spanner on the nut and undo a little ...

Hi Steve,

I see that you took the photograph today. Thank you for that. I'd be grateful if you could get an open ended spanner on your striker to see if you can shift it. If you can, I'll be convinced.

Simon

Lee62 · 5th December 2021, 18:55

This design is used on many cars. The nut under the spring is a lock nut but shouldn't be too difficult to undo. If you could loosen the pin with just a screwdriver the pin would gradually move and alter the position the bonnet locks in place. If it really is too tight a space grind down an old 17mm to fit in the space. The thread in the photo looks well mullered and could be causing the tightness.

Arctic · 5th December 2021, 20:31

Quote:

Originally Posted by SD1too

Hi Steve,

I see that you took the photograph today. Thank you for that. I'd be grateful if you could get an open ended spanner on your striker to see if you can shift it. If you can, I'll be convinced.

Simon

Hi Simon.
It is a locking nut only, the thread is in the plate it's self, but as they do need to be maintained i will give mine a clean and grease tomorrow and convince you

T-Cut · 5th December 2021, 21:11

Slackening (then tightening) the locking nut requires you to force an open ended spanner between the spring and the bonnet plate. Maybe use a blade to lever a gap and then force the spanner in. Maybe MGR had a special tool for this, but for me it was more like a bull-at-a-gate than engineering finesse.

TC

5th December 2021, 09:03	#1
SD1too Doesn't do things by halves Rover 75 2.5 Connoisseur Auto (1999) Dealer launch model. Join Date: Mar 2007 Location: Former Middlesex Posts: 20,344 Thanks: 1,587 Thanked 3,749 Times in 3,181 Posts	Bonnet striker puzzle Has anybody managed to adjust their bonnet strikers ( the two spring loaded plungers screwed to the bonnet lip)? The design hasn't changed in 50 years and I'm sure that on previous cars I simply inserted a stout screwdriver into the slot cut into the tapered end of the striker and turned it. I'm working on someone else's 75 and even after removal to a vice, the striker shaft would not turn even by one degree! It's obviously seized with corrosion I concluded. Penetrating fluid and considerable torque failed to release it so since new ones are a reasonable price I ordered a pair. Now here's the puzzle. These won't move either! I just need to raise the RH side of the bonnet to be level with the wing (and yes, the rubber stop is already at full height). Has anyone else encountered this? Simon __________________ "Whatever is rightly done, however humble, is noble." Sir Henry Royce.

5th December 2021, 10:17	#2
rovertone Gets stuck in Rover 75 Conne SE Auto CDTi Join Date: Nov 2012 Location: Redditch Posts: 667 Thanks: 185 Thanked 135 Times in 109 Posts	Hi Simon, Sorry if this is stating the obvious but you have slackened the pin lock nuts before trying to adjust via screwdriver slot? Tony __________________ 2003 Mk 1 Connie SE CDTi Auto Monogram Mirage 2/Sandstone Leather 511th CDTi out of 4744 produced 9th in Mirage 2 out of 17 produced Also 2004 Rover 25 SXi CVT, 1999 Megane Cabriolet and still missing my 800 Fastback.

5th December 2021, 18:55	#8
Lee62 Newbie Rover 75 Join Date: Nov 2018 Location: Ware Posts: 9 Thanks: 0 Thanked 1 Time in 1 Post	Bit of an ask This design is used on many cars. The nut under the spring is a lock nut but shouldn't be too difficult to undo. If you could loosen the pin with just a screwdriver the pin would gradually move and alter the position the bonnet locks in place. If it really is too tight a space grind down an old 17mm to fit in the space. The thread in the photo looks well mullered and could be causing the tightness.

5th December 2021, 21:11	#10
T-Cut This is my second home Rover75 and Mreg Corsa. Join Date: Nov 2006 Location: Sumweer onat mote o'dust (Sagin) Posts: 21,752 Thanks: 341 Thanked 3,660 Times in 2,924 Posts	Slackening (then tightening) the locking nut requires you to force an open ended spanner between the spring and the bonnet plate. Maybe use a blade to lever a gap and then force the spanner in. Maybe MGR had a special tool for this, but for me it was more like a bull-at-a-gate than engineering finesse. TC Last edited by T-Cut; 5th December 2021 at 21:21..

5th December 2021, 16:53	#5
Typhoon190 This is my second home MG ZT-T 190 Monogram Typhoon Join Date: Jan 2009 Location: Oxfordshire Posts: 4,704 Thanks: 328 Thanked 557 Times in 443 Posts	Having disassembled the striker plate assembly before, the nut is there to lock the pin in position, so it will be tight but can be slackened and removed if needed.