[Healeys] BN2 Caster Angle

Bob Spidell bspidell at comcast.net
Wed Jan 6 10:05:09 MST 2021 

re: "The whole front end is sat on those two Oilite bronze thrust washers."

Nope. Proof: I have placed my cars on jackstands under the rear springs 
and front trunnions and R&R'd their shock absorbers several times 
(Armstrong shocks are a PITA, but that's a different rant). Risky? 
Maybe, but done right the risk is manageable. My BJ8 rode through a 
Richter 5+ earthquake in this state in San Jose a few years ago; 
obviously, a flat, rugged concrete surface is required (note messing 
with massive springs under compression has risks as well). My BN2 is now 
in this state while I wait for front shock rebuilds (though I have the 
jackstands backed-up by a QuickJack under the chassis).

Though there is a very specific gap called-for for the top trunnion, the 
only reason I can see is too small a gap might cause some 
binding--leading to even more steering effort--and too large could 
result in the shock and bushing/bearing taking a beating.


On 1/6/2021 7:39 AM, bluehealey at gmail.com wrote:
>
> Hi Fred.
>
> You are not the first person that I have encountered with this 
> confusion. It is usually held by those that are very familiar with 
> pre-war cars and beam axles. In those cars the steering/stub axle is 
> captured between fixed top & bottom ‘ears’ on the end of the beam.  
> The weight of the car bears down through the top ear onto the swivel 
> axle. All fairly obvious.
>
> In the case of our cars, with top and bottom wishbones, the weight of 
> the car is carried on the spring and bottom wishbone. The wheel and 
> stub axle is bearing upwards, LIFTING the car through the top trunnion 
> using the kingpin as a pull-rod to the bottom wishbone and spring.
>
> The whole front end is sat on those two Oilite bronze thrust washers. 
> Any reduction in friction here pays dividends – especially in a 
> 6-cylinder car with even more weight over the wheels.
>
> Maybe others can come up with a clearer explanation.
>
> Cheers.
>
> AlanB
>
> *From:*Fred Wescoe <fredwescoe at gmail.com>
> *Sent:* 06 January 2021 15:14
> *To:* Bluehealey <bluehealey at gmail.com>
> *Cc:* Team.net <lawrence.swift at gmail.com>; Ahealey help 
> <healeys at autox.team.net>
> *Subject:* Re: [Healeys] BN2 Caster Angle
>
> Listers,
>
> I have looked at these top trunnion bearing kits over the years and 
> considered installing them.  However, I simply cannot get my head 
> wrapped around why replacing bearings at the top of the kingpin would 
> reduce the weight of the car and improve steering.  It seems to me 
> that all the weight of the car is pressed against the bottom of the 
> kingpin.  To me, it seems replacing the top bearing would have no 
> effect on the steering effort.  Can someone explain in simple language 
> why this kit would work?
>
> Thanks, mystified,
>
> Fred
>
> 66 BJ8
>
> On Wed, Jan 6, 2021 at 9:49 AM Bluehealey <bluehealey at gmail.com 
> <mailto:bluehealey at gmail.com>> wrote:
>
>     These are the ones.
>
>     https://www.ahspares.co.uk/austin-healey/big-healey/suspension-front/top-trunnion-bearing-kit-pair.aspx
>     <https://www.ahspares.co.uk/austin-healey/big-healey/suspension-front/top-trunnion-bearing-kit-pair.aspx>
>
>     Well worth doing.
>
>     The other often overlooked source of heavy steering is the
>     Steering Idler. It is rarely lubricated, has no real reservoir for
>     oil, and a poor seal at the bottom. I suggest releasing the ball
>     joints that connect to the drop arm to check it for stiffness.
>     Complete removal of the idler isn’t a difficult job and is the
>     best way to clean and lubricate.
>
>     The caster is pretty good on these cars (the initial design was
>     good). Camber could go from positive to negative to be more
>     compatible with radial tyres. Also check and minimise toe-in. This
>     has a radical impact on steering feel when wrong (in either
>     direction).
>
>     If after all that you still have problems, then go for the caster
>     changes you have in mind and tell us about your findings. The Team
>     may learn something.
>
>     The only other aspect that seems to vary from car to car is bump
>     steer. Some can be horrible on fast bumpies and others are on
>     rails.  I’ve never seen a decent treatise on dealing with this on
>     our Big Healeys.
>     Have fun.
>
>     Alan - from my iPad
>
>
>
>         On 6 Jan 2021, at 13:35, Team.net <lawrence.swift at gmail.com
>         <mailto:lawrence.swift at gmail.com>> wrote:
>
>         When I rebuilt the front end on my BT7, I had the trust
>         bearings at the top of the kingpin replaced with bearings -
>         made a huge difference in the ease of steering.
>
>
>             On Jan 5, 2021, at 10:36 AM, Bob Spidell
>             <bspidell at comcast.net <mailto:bspidell at comcast.net>> wrote:
>
>             re: "The other two are factory fixed and too dangerous to
>             play with or maintain...even if Kilmartin makes the parts"
>
>             How so?
>
>             On 1/4/2021 9:40 PM, gradea1 at charter.net
>             <mailto:gradea1 at charter.net> wrote:
>
>                 I'm with the philosophy "set the toe and let 'er blow"
>                 The 1/16-1/8" toe-in is most important for proper tire
>                 wear.  The other two are factory fixed and too
>                 dangerous to play with or maintain...even if Kilmartin
>                 makes the parts. Hank
>
>             _______________________________________________
>
>             Support Team.Net http://www.team.net/donate.html
>             <http://www.team.net/donate.html>
>
>             Suggested annual donation  $12.75
>
>             Archive: http://www.team.net/pipermail/healeys
>             <http://www.team.net/pipermail/healeys>
>             http://autox.team.net/archive <http://autox.team.net/archive>
>
>             Healeys at autox.team.net <mailto:Healeys at autox.team.net>
>
>             http://autox.team.net/mailman/listinfo/healeys
>             <http://autox.team.net/mailman/listinfo/healeys>
>
>             Unsubscribe/Manage:
>             http://autox.team.net/mailman/options/healeys/lawrence.swift@gmail.com
>             <http://autox.team.net/mailman/options/healeys/lawrence.swift@gmail.com>
>
>
>         _______________________________________________
>         Support Team.Net http://www.team.net/donate.html
>         <http://www.team.net/donate.html>
>         Suggested annual donation  $12.75
>
>         Archive: http://www.team.net/pipermail/healeys
>         <http://www.team.net/pipermail/healeys>
>         http://autox.team.net/archive <http://autox.team.net/archive>
>
>         Healeys at autox.team.net <mailto:Healeys at autox.team.net>
>         http://autox.team.net/mailman/listinfo/healeys
>         <http://autox.team.net/mailman/listinfo/healeys>
>
>         Unsubscribe/Manage:
>         http://autox.team.net/mailman/options/healeys/bluehealey@gmail.com
>         <http://autox.team.net/mailman/options/healeys/bluehealey@gmail.com>
>
>     _______________________________________________
>     Support Team.Net http://www.team.net/donate.html
>     <http://www.team.net/donate.html>
>     Suggested annual donation  $12.75
>
>     Archive: http://www.team.net/pipermail/healeys
>     <http://www.team.net/pipermail/healeys>
>     http://autox.team.net/archive <http://autox.team.net/archive>
>
>     Healeys at autox.team.net <mailto:Healeys at autox.team.net>
>     http://autox.team.net/mailman/listinfo/healeys
>     <http://autox.team.net/mailman/listinfo/healeys>
>
>     Unsubscribe/Manage:
>     http://autox.team.net/mailman/options/healeys/fredwescoe@gmail.com
>     <http://autox.team.net/mailman/options/healeys/fredwescoe@gmail.com>
>
>
> <https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=emailclient> 
> 	Virus-free. www.avast.com 
> <https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=emailclient> 
>
>
> <#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>
>
> _______________________________________________
> Support Team.Net http://www.team.net/donate.html
> Suggested annual donation  $12.75
>
> Archive: http://www.team.net/pipermail/healeys http://autox.team.net/archive
>
> Healeys at autox.team.net
> http://autox.team.net/mailman/listinfo/healeys
>
> Unsubscribe/Manage: http://autox.team.net/mailman/options/healeys/bspidell@comcast.net
>

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://autox.team.net/pipermail/healeys/attachments/20210106/dbbe925e/attachment.htm>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image001.png
Type: image/png
Size: 13262 bytes
Desc: not available
URL: <http://autox.team.net/pipermail/healeys/attachments/20210106/dbbe925e/attachment.png>

More information about the Healeys mailing list