Front tire shimmies

[JeffMoore64]

Good evening all,

First off, thanks to all the advice I've been given so far! I have my TC up and running. Bubbling radiator and timing pretty much fixed, have it set for 8 degrees + of TDC and power seemed to come up a bit and bubbling, while still then is much more modest. Also got the radiator drain cock out, cleaned, and installed with no damage to the radiator.

So I took her out for a short drive and at about 40 mph (speedo is broken) the front wheels started into a harmonic vibration. When away once I slowed down about 5 - 10 mph and started right back up when I hit about 40 - 45 mph. So the question I have is does anyone know the root case of this? I noticed that the rubber in the linkage to the shocks is pretty much shot, so that needs to be replaced. Anything else I should be aware of or check?

Thanks,

Jeff

[Duncan M]

Jeff- Find a smooth road surface where dampers do nothing to confirm that is not the cause. Keep in mind the steering mechanics of a TC are unique to only PreWar MG's and the TC. First thing I would check is that the wheels are not loose. With the front wheelsl off the ground, give each a spin to check for bent rims or rims out of true. Eyeball it for now. If neither of those problems is obvious then look into the drag link and end links, as they are a more likely cause. These are the "ball and socket" joints at the ends of the steering links that turn the road wheels when you turn the steering wheel. The drag link wears the most; it is the first link coming off the drop arm from the steering box. Similar joints are at the ends of the tie rod's. A grease fitting lubes these joints, and at their outer ends there is a plug held in place with a cotter (split) pin. The inner side of the plug is one side of the "socket" into which the "ball" fits. That plug screws in and out, and proper adjustment gives the correct tension on the joint. Really quite simple to screw it all the way in and then back off 1/4 or 1/2 turn, but you should read this article in issue 23 of Totally T-Type 2 before you do anything, as there are several other things to check for as long as you are there. Beginning page 6. http://ttypes.org/ttt2/pdf/TTT2-Issue23.pdf

[Julian Evers]

Get the wheels fully balanced (all 5). It never ceases to amaze me how few 19" wheels are balanced when I go to a M.G. meeting. Yes, you need to go to a tyre place that has the cones or get your own (MWS in Langley UK will sell them) but consider the diameter of the wheel and how it will multiply the out of balance forces. I accept that the stick on weights might be considered unsightly by some but think of the protection you are affording the front axle and steering by removing the vibration. There is one side effect, you will find yourself driving faster.

Best regards Julian

[Clifford Jay Lockrow]

All ot the items mentioned should be checked but eventually you should also check your toe in. I believe the brown book lists the toe in a 3/16. Make up some sort of measuring device and check and then roll the car a few feet forward and then back to check again. If your wheels have any "wobble" this could make a huge difference.
Try driving the car over a set of railroad tracks or a slick manhole cover and on my TC I have had this set up a heavy shake or shimmy. Adjusting the toe in has always cured the situation. You have a few hours workahead of you but this is all part of owning a TC!

[stephen stierman]

All good advice and I would certainly take a look at how true the wheels actually are. If they are well out of true, it would certainly be a good idea to spend some time getting them back into shape. Additionally proper toe in will make the car wander a lot less, adding a bit more toe was the single adjustment that contributed greatly to increased stability on my car.

[Steve Simmons]

And the tires themselves can be alarmingly out of round!

[Gene Gillam]

And lastly, check the tie-rod ends. I believe the book says to tighten the end to where you can just get the cotter in. A lot of times this leaves a bit of slack and you'll get a resonance set up because the spring can compress and uncompress a little, giving you a shimmy (and sometimes a death shake). I normally cut a cross in the end piece so I can tighten them a bit tighter.

Works for me.

Gene