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Brandon
08-29-2011, 09:25 AM
I have a 1962 TVR Grantura MKIIA with a MGB engine and I am having some problems with wheel wobble. I am hoping that someone on this forum might be able to help me. My car has knock off wheels and the other day my wife was following me down the road and noticed that the right rear wheel had a wobble. I jacked up the rear end and noticed that the right rear wheel would spin easy and it would get hard in a spot and then rotate free then hard again. The two “hard” spots were about 180 degrees from each other. Upon removal of the wheel, the hub would turn the same way, with two “hard” spots. Once I removed the brake drum, the axle would turn free with no “hard” spots. Is the brake drum bad/out of balance or is it something else? Also, is the brake system from an Austin Healey?

gtemkin
08-29-2011, 03:12 PM
Yes, the brake drum is likely out of round (not balance), but that's fairly typical and generally shouldn't be of terrible concern. You may try backing off on the brake shoe adjuster(s) until the stiff spots diminish. It's OK to have some slight stiff spots, but if it takes two hands to rotate the wheel, then that's probably too much. Do understand that the further you back the adjusters off, the further will be your pedal travel, so you're looking to back them off just enough, but no more. You could get the drums turned, but that may have been done so many times in the past that they may be un-turnable and you may need to replace them. By the way, make sure you're parking brake is not the source of the problem; I don't mean just the handle, but you've got to make sure the cables or rods are allowing the brake shoes to return completely.

The bigger concern is the wheel wobble, and that's a true safety concern, which I think may not have any relationship to the brake binding. You should verify if the wheel is bent, or if it's something else causing the wobble; and you should do that before you drive the car much in case there's a really bad problem like a badly bent drive flange or something.

Gregg

DrEntropy
08-30-2011, 04:39 AM
The bigger concern is the wheel wobble, and that's a true safety concern, which I think may not have any relationship to the brake binding.

Totally agree. Bent flange, worn splines... find/figure out what's really the problem before you have a "Holy Carp!" moment.

You will need to thoroughly clean the hub splines/threads and reinstall the wheel, then without spinning it see if there's play up and down, or side to side by applying opposite force at 180° on the tire north-south, east-west. If you get movement, the hub is likely worn. If not, rotate the wheel with an "index" of some sort (a couple 2x4's and a protruding piece of wire at wheel-edge height... Think: MacGyver) to see if the wheel is out of "true".

Let us know what you find.
<span style="font-style: italic">
EDIT: Block, brace the car WELL (jackstands!) when doing all this! SAFETY, please.</span>

Grantura_MKI
08-30-2011, 08:33 AM
Most likely a bent quill shaft.

DrEntropy
08-30-2011, 03:44 PM
Is there enough torque in a B engine to DO that with as light as that back end is, D? Or did they use a thinner-than-MGB shaft for the sake of "lightness"?

Silly me for askin' YOU! :jester:

To check before disassembly, a wheel swap front to rear would tell, methinks. Bent wheel wobbles on any hub. Bent shaft makes a good (true) wheel look wobbly.

gtemkin
08-30-2011, 11:23 PM
<span style="font-style: italic">EDIT: Block, brace the car WELL (jackstands!) when doing all this! SAFETY, please.</span>


I once saw a car drop when a cold weather front came through, because the cinder blocks someone had used to hold the car up gave up the ghost from the extreme temperature change. It didn't help that the frame of the car was directly point loaded onto the blocks, but they literally turned to dust in an instant after having held the car up for several days. Thankfully, no one was near the car. As DrE says, don't fool around - real jackstands, well placed are a must.

Gregg

DrEntropy
08-31-2011, 06:34 AM
Yes, Gregg! :iagree:

I was in no way advocating <span style="font-style: italic">cinderblock</span> as a jackstand device! :eeek:

...I gotta watch what I post (at least when being serious). :wink:

A piece of 2x6 in-between, and compression loading the block with the openings vertical would have been better. But still not a good answer.

elrey
08-31-2011, 10:31 AM
Yeah! :iagree: Everybody knows that cinder blocks are for front yard display purposes only!

DrEntropy
08-31-2011, 04:19 PM
Yeah! :iagree: Everybody knows that cinder blocks are for front yard display purposes only!

And only here below th' Mason-Dixon Line. "Up North" we used old steel wheels. :jester:

Grantura_MKI
08-31-2011, 04:45 PM
Hi Doc,
Yes, they can snap or bend with the "B", or Ford lump. The weak area is at the tapper after the broach. You need to also remember that we are dealing with a 50+ year old quill shaft.
I have snapped an axle on my slightly "tuned" MGB fitted with wires.
Brandon maybe a new keeper of this TVR, so who knows what the previous keeper's have done?
OK, goning back to stack my cinderblocks.

DrEntropy
09-01-2011, 06:23 AM
Hmm. Never gave MGB axles a thought, never had one snap. Ford ones, yeah. The chunk in the Elans is also Ford, short stub-axles with a thin (same diameter as the original Ford) shaft. The +2 has a pair of the Dave Bean beefier stubs after having snapped one in traffic. :shocked:

I recall TVR used both but figured if it was the B diffy the shaft would be the last thing to go after. My bad.


also remember that we are dealing with a 50+ year old quill shaft. Brandon maybe a new keeper of this TVR, so who knows what the previous keeper's have done?

Has it really been that long?!? :jester:

...and yes, only logical to assume the car has seen th' stick many times in its life. Too much fun NOT to do! :wink:

Grantura_MKI
09-01-2011, 08:45 AM
Many a TVR has been three wheeled at some point in it's life. Now wait...does that make the TVR part Morgan?