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Trunnion roller bearings

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healeyneil

healeyneil

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Having just fitted roller bearing top trunnion bushes i have a few questions to ask
1) Setting up - no information was provided so I assembled mine then shimmed them to get correct clearance. correct?
2) lubrication. How does grease get to these bearings in use? The original oilite bushes were still Ok ( I have carefully stored them! )
3)Any experience of these bearings "on the road"
 
[ QUOTE ]
Having just fitted roller bearing top trunnion bushes i have a few questions to ask
1) Setting up - no information was provided so I assembled mine then shimmed them to get correct clearance. correct?
2) lubrication. How does grease get to these bearings in use? The original oilite bushes were still Ok ( I have carefully stored them! )
3)Any experience of these bearings "on the road"

[/ QUOTE ]

#1] Correct

#2] same way it got to the oilte ones, should be packed prior to installation.

#3 NO
-------------------------------------------------Keoke- /ubbthreads/images/graemlins/hammer.gif
 
healeyneil said:
3)Any experience of these bearings "on the road"
Click to expand...

Yep. After I fitted a larger/stiffer anti-sway bar on my BJ8 it broke the camel's back (the 185/70-15 radials on 6-inch rims and a smaller-than-stock Derrington steering wheel were bad enough). So, I fitted the roller upper trunnion bearings. I wasn't expecting miracles, but was delighted with the decrease in steering effort, esp. at slow speed (parking, etc.). I even think they help at high speed too, though some people don't.

Why don't you drive your car and see for yourself?
 
I've used them on my '57 100-6 MM vintage racer for the past 3 years, very happy with the results. I run with 1% negative camber, Hoosier Vintage TD's bias- ply race tires on 6.5" Superlite rims and 1" front sway bar.

Dougie
 
will fit mine next time I have some quality garage time available based on the views above. what clearance are people looking for? I'm assuming a feeler gauge between swivel axle and trunnion will work to measure? thanks
 
chapelfarmer said:
... what clearance are people looking for? I'm assuming a feeler gauge between swivel axle and trunnion will work to measure? thanks
Click to expand...

The bottom of the trunnion and the top of the axle overlap--I don't know how you'd get a feeler gauge in there. If you find a way, let us know (you'd probably have to use a dial mic with a mag base, etc.).

IIRC (not sure--too lazy to look it up), the book spec is 1-2 thousandths of an inch for the flat bushings. I just packed shims until I could feel only the slightest up/down movement; i.e. just enough clearance so there's no preload on the bearing when the wheel is suspended so there's no weight on that axle. The car's weight that's borne by a wheel is pressing on the bearing at rest/normal ride--you'd want minimal clearance to keep the trunnion and axle from pounding the bearing as the wheel moves up and down. That's my theory, anyway; if there's an official explanation I'd love to hear it.

I think it took more-or-less 0.035" of shims on each side for my BJ8. I used the same shims used to set wheel bearings as per a pro's recommendation.
 
Factory Manual calls for maximum permissable lift of .002"

I strive for .0005" - .001" endfloat.

hnr_031.jpg


I made my own pilots for the reamers

hnr_023.jpg
 
If you have recently fitted new bushings and shims and want to upgrade, simply measuring the stack of shims required for one side and subtract the thickness of the replacement trunnion bearing upgrade. After you refit the shim pack use a dial test indicator and recheck the end float. I would strive as Randy indicates for between .0005 and .001 inch end float fitted dry. Once the end float is set then take the assembly apart and lubricate the shims and bearing for final fitting. This is not a quick processā€¦
 
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