Odd bolts

Peterv

Active Member
Hi All.
I pulled the rear shocks out today to check their condition and found these bolts holding the bottom plate to the lower suspension link arm.
They look like they are there for a particular purpose but they all have seen better days.
Can they be replaced with ordinary bolts and if not, are they unobtainable.

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The are paint clearing screws , used in parts that may have paint in the threaded holes . Its not one I have seen on a P6 and can , if you want, be replaced by ordinary High tensile bolts ( Normally R or S grade) of the same thread
 
The are paint clearing screws , used in parts that may have paint in the threaded holes . Its not one I have seen on a P6 and can , if you want, be replaced by ordinary High tensile bolts ( Normally R or S grade) of the same thread

You learn something new every day - I always wondered why they were a peculiar type of bolt.
 
If I recall correctly, Harvey explained that the threads within the trailing arms were not finished, and these bolts were used to complete the task. The spiral grooves are to allow swarf to pass as the bolt completes cutting the thread.

As was mentioned, you can indeed replace them with oridinary grade 5 high tensile bolts, identified by three lines on the head equally spaced by 120 degrees.

Ron.
 
Thanks for that guys, thought they may be a type of locking bolt I'd not come across before.
Great idea John. Will run the best one through all the holes as my new bolts are rather tight. (Otherwise a tap will be used)
 
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All sorted. Tapped, HT bolts, lock washer and Loctite. That'll hold.
Just to throw the cat amongst the pigeons, found this article when trying to identify those bolts above.
I don't necessary agree or disagree but just something to keep in the back of your mind to bring up at the pub one day.

10 Tricks Engineers Need to Know About Fasteners
 

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Good spotting. They came on the car so can't compare but they do ride very well together with the Monroe shocks And they look good :LOL:
 
What's the part number for the Monroe shock Peter. I'm doning the rounds on replace shocks on my cars and my Rovers next. Also for the Front if you have that as well.

Cheers,
Craig
 
What's the part number for the Monroe shock Peter. I'm doning the rounds on replace shocks on my cars and my Rovers next. Also for the Front if you have that as well.

Cheers,
Craig
The Monroe's were on the car when got it so can't help you there. I pulled them off to check their condition and reinstalled as they are fine.
However, I did replace the fronts recently with GAZ adjustable shocks. Got them from Rimmers in the UK. (best price) but with freight and GST it becomes an expensive exercise. (a smidgen over 5 hundy) They can transform a car when set to your liking. The Koni's that were on before are still fine but I like playing around hence the adjustables.
Cheers, Peter
 
The Monroe's were on the car when got it so can't help you there. I pulled them off to check their condition and reinstalled as they are fine.
However, I did replace the fronts recently with GAZ adjustable shocks. Got them from Rimmers in the UK. (best price) but with freight and GST it becomes an expensive exercise. (a smidgen over 5 hundy) They can transform a car when set to your liking. The Koni's that were on before are still fine but I like playing around hence the adjustables.
Cheers, Peter
Thanks Peter.
 
Continuing with the bolt theme, here is a technical paper on mechansims and prevention of loosening in bolted joints. The paper is written by Dr Saman Fernando, a professional engineer with a PhD in Aerodynamics and Thermodynamics.
hobson-technical-paper-bolting-vibration.pdf

A point to note is that torque and tension are quite distinct. Torque is the application of a force applied to a lever arm at a distance from the point of application. The SI units for torque in their simplest form are Newton metres (Nm). Tension is a force applied through the longitudinal axis in the case of bolt. The SI units of tension are Newtons (N).

Ron.
 
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