Re: Drop arm installation and pinch bolt

[Pavone, John (Corporate)]

Which direction does the angled drop arm point (up or down), when installed on the steering box sector shaft? Also, what is the correct torque spec for the drop arm pinch bolt? It's a grade 5 5/16" type.

Thanks.

JP

TC2797

[Roger Furneaux]

hi John - early arms were straight, later ones bent down to make sure the
drag link cleared the sump. In both cases the arm is installed such that the
tapered seat ball is underneath. That is the reason for the draglink end
having a slot to prevent it falling off the ball (although not all suppliers
know or care about this, and only stock one type of rod end).
I would strongly recommend that you use a modern cap-head bolt of ISO 12.9
grade (it can be 8mm), much stronger than the average hex-head, use an
aerotight (all metal) self-locking nut, and torque it to 33 lbsf. ft. These
bolts stretch, allowing the drop arm to get loose on the splines, which will
ultimately get damaged, so need to be checked for tightness on a regular
basis. Bolts are cheap, so preferably replaced every 10,000 miles or so.
Your grade 5 bolt is roughly equivalent to an ISO 8.8, could have been
overtightened in the past, and should be thrown away.

ocTagonally

TCRoger in Olde England

John Pavone wrote from New England:

>Which direction does the angled drop arm point (up or down), when installed
>on the steering box sector shaft? Also, what is the correct torque spec for
>the drop arm pinch bolt? It's a grade 5 5/16" type.

[Non-text portions of this message have been removed]

[Pavone, John (Corporate)]

Hi Roger,

My car had an incorrect rod end on the drop arm side but I was able to get the correct one from Skip Kelsey.

The pinch bolt is a new Airframe type with a military spec all metal locknut, which I bought through an race car supply shop. I assume that this should be more than adequate for this application but I'll be sure to check it's tightness on a regular basis.


Thanks for the information!

Best Regards,

John

-----Original Message-----
From: Roger Furneaux [mailto:Roger.46TC@virgin.net]
Sent: Wednesday, August 24, 2005 7:25 AM
To: Pavone, John (Corporate)
Cc: .T-ABCs
Subject: Re: [mg-tabc] Drop arm installation and pinch bolt



hi John - early arms were straight, later ones bent down to make sure the drag link cleared the sump. In both cases the arm is installed such that the tapered seat ball is underneath. That is the reason for the draglink end having a slot to prevent it falling off the ball (although not all suppliers know or care about this, and only stock one type of rod end).
I would strongly recommend that you use a modern cap-head bolt of ISO 12.9 grade (it can be 8mm), much stronger than the average hex-head, use an aerotight (all metal) self-locking nut, and torque it to 33 lbsf. ft. These bolts stretch, allowing the drop arm to get loose on the splines, which will ultimately get damaged, so need to be checked for tightness on a regular basis. Bolts are cheap, so preferably replaced every 10,000 miles or so.
Your grade 5 bolt is roughly equivalent to an ISO 8.8, could have been overtightened in the past, and should be thrown away.

ocTagonally

TCRoger in Olde England

John Pavone wrote from New England:

>Which direction does the angled drop arm point (up or down), when installed
>on the steering box sector shaft? Also, what is the correct torque spec for
>the drop arm pinch bolt? It's a grade 5 5/16" type.

[Non-text portions of this message have been removed]