knocking wheel

Beetle, Karmann Ghia, Thing.

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zabo
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knocking wheel

Post by zabo » Wed Nov 21, 2012 5:59 pm

noticed a knocking from my rear wheel at low speeds, maybe its there at higher but cant tell.

Pulled the drum and everything looked fine- tightened up everything while i was there, trans oil good... noise still happening :scratch:
60 beetle
78 bus

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hambone
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Re: knocking wheel

Post by hambone » Wed Nov 21, 2012 6:13 pm

Bearings? CVs?
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Amskeptic
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Re: knocking wheel

Post by Amskeptic » Wed Nov 21, 2012 7:02 pm

hambone wrote:Bearings? CVs?
No CVs on that car.
[jewish mother kvetch on]
You would have KNOWN that if Zabo had MENTIONED the YEAR of his car so we can TRY to answer his question . . .
[jewish mother kvetch/off]

Zabo, jack it up and use stands under the shocks so both rear wheels are off the ground but under suspension load.
Start engine and accelerate in 3rd gear to mid-range, clutch in/shut off engine and listen for bearing noise as wheels spin down. Feel for any mechanical ticks coming through body shell.

IF YES: bearing problem
IF NO: repeat above and gently apply ebrake as wheels spin down and listen for same noise.
IF YES: drum out-of-round kicking shoes and ebrake lever
IF NO: test bearings while coasting down abandoned quiet smooth road with engine off and report back.
ColinSureI'llReplyInATimelyManner
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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zabo
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Re: knocking wheel

Post by zabo » Wed Nov 21, 2012 9:03 pm

Yes i did fail to mention the year: 1960, 40hp engine/ later swingaxle. :flower:
One other clue- this evening the sound was more pronounced on deceleration, braking seemed to have no effect.
The knocking is pretty rhythmic but then gets a little out of step.

Colin I'll try the test you mentioned above. This morning i did try going through the gears on stands but heard nothing.

It will probably be the weekend before i report back with findings.
60 beetle
78 bus

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Amskeptic
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Re: knocking wheel

Post by Amskeptic » Fri Nov 23, 2012 8:51 am

zabo wrote:Yes i did fail to mention the year: 1960, 40hp engine/ later swingaxle. :flower:
One other clue- this evening the sound was more pronounced on deceleration, braking seemed to have no effect.
The knocking is pretty rhythmic but then gets a little out of step.

Colin I'll try the test you mentioned above. This morning i did try going through the gears on stands but heard nothing.

It will probably be the weekend before i report back with findings.
More pronounced on decel steers us towards wheel bearing/drums. Please be extremely alert to the following:
An intact axle nut/cotter pin does NOT prove that the axle nut is tight enough! The spacer can wear, reducing the torque of the axle nut to a damaging degree that accelerates wear. Please feel free to remove the cotter pin and see if the axle nut has loosened. Your axle nut specification is 253 ft/lbs on that car?
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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zabo
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Re: knocking wheel

Post by zabo » Sun Nov 25, 2012 7:55 am

no bearing noise on jack up test or ebrake noise.

After another test drive this morning I have to say it is dependent on braking.
I hear no general bearing noise on the hill test.
The knocking does not seem to appear until the car is thoroughly warmed up.
I am confident axles are torqued sufficiently.
The ebrake is also not working on the left side although all linkage was intact when i checked the other day.

Will take drum off again to inspect once it warms up- freezing here this morning! Image
60 beetle
78 bus

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zabo
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Re: knocking wheel

Post by zabo » Sun Nov 25, 2012 2:43 pm

it looks like my left ebrake cable is stretched/frayed- will pick up a new on tuesday.

I dont think thats making the noise but i guess its possible if the lever does not have enough tension on it.
60 beetle
78 bus

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Amskeptic
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Re: knocking wheel

Post by Amskeptic » Mon Nov 26, 2012 8:40 am

zabo wrote:it looks like my left ebrake cable is stretched/frayed- will pick up a new on tuesday.

I dont think thats making the noise but i guess its possible if the lever does not have enough tension on it.
The cable applies no tension whatsoever to the lever. The spring on the cable merely ensures that the ebrake releases fully by *pushing* the clevis rearward. The shoe return spring actually pulls the ebrake lever forward, thus the two are attempting to make space between the cable clevis and the lever.
BUT
your intuition may be picking up on the fact that a frozen/frayed/damaged ebrake cable has been known to bow inside the brake drum area and it can rub against a rotating drum.
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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zabo
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Re: knocking wheel

Post by zabo » Sun Dec 16, 2012 8:00 am

well after more than a week of road testing i have to say the new ebrake cable seems to have been the remedy.
60 beetle
78 bus

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Amskeptic
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Re: knocking wheel

Post by Amskeptic » Mon Dec 17, 2012 7:47 am

zabo wrote:well after more than a week of road testing i have to say the new ebrake cable seems to have been the remedy.
And you get to enjoy nice handbrake action too.
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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