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Old 24-05-15, 18:28
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cordenj cordenj is offline
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Join Date: Mar 2009
Location: Surrey UK
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Back from the Guernsey 70th Anniversary trip (in the Jeep) and now back to trying to resolve the Chev's Wheel Shimmy.

As two heads are better than one, I asked good friend, expert mechanic and fellow CMP owner, Andy to give me a hand to investigate further.

We spent all day yesterday working through the front axle.

Started by checking and slightly tightening the steering box. A test drive showed some improvement but a dose of major shimmy meant more investigation was required.

As some have said here, we think this is a combination of different factors that cumulatively cause the issue.

So logically it is a case of going through each possible cause and trying to eliminate it ,apart from what I've already listed earlier in the thread:

1. Steering Gear - checked, adjusted and ok
2. Front Axle tie rod - checked and in good condition
3. Wheel bearings - both sides are correctly set and in good condition
4. Pivot Pin bearings:
Near-side_steering knuckle binding slightly in the the chromed housing. Checked shimming and reset to avoid binding. Both bearings in good condition.
Off-side_steering knuckle binding in the the chromed housing. We think this side was overshimmed and had placed great pressure on the Pivot Bearings....unfortunately both need to be replaced....so will be trying to contact Dirk or Stefan on Monday for replacements.
We suspect that this wheel shimmy is not a new issue on this vehicle and that the bearings had been very tightly shimmed in an attempt to stop it.

5. Front springs - The photos below show the front springs, which have clearly sagged over the last 70 years......and as several posters on this thread have suggested, this is probably the a major contributor to the shimmy issue and the caster will be way out.
Close examination of the photos show some small wedges have been fitted in the past. My plan now is to try to get a pair of larger wedges machined a at a local engineering shop.

Once new Pivot bearings hopefully sourced and are fitted and the new wedges are placed between the spring and axle....and we'll see what happens.

Can't help feeling the real solution is a replacement set of good front C60S springs which can restore the correct caster. Anybody know of any in UK, Belgium or Netherlands?
Attached Thumbnails
IMG_0163 (1024x768).jpg   IMG_0172 (1024x768).jpg  
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1944 Chevrolet C8a HUP ZL-2
1944 Willys MB (British Guards Armoured Div);
1944 BSA Folding Bicycle (Best "Para Bike" at War&Peace Show 2011, 2012, 2014 and 2015);
Trailer, 10cwt, Water Lightweight, 100 gall;
Trailer, 10cwt, Cargo Lightweight 10cwt No1 MkII;
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SOLD:1943 Chevrolet C60s Wrecker
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