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MG MGB Technical - MGB not running straight, need help

Good day all! I searched the archives but could not find a thread re my problem.

I just bought a 1971 MGB which is in very good condition, however, my wife noticed (she followed me home when we bought it) that the rear of the car seems to be a bit to the right. After inspecting, I noticed that the right rear wheel is not straight but pointed to the inside (toe-in). The right wheel is fine. The steering wheel also is turned a bit to the right when going straight. Is this an alignment problem? Any advise would be appreciated.

I will bring it to the shop but would like to know the likely cause beforehand before they run up the $80/hr labor charge!

Thanks!
napoleon

Very confused here napoleon. There is a live rear axle on MGB's and they should have 0 degrees toe in and camber. I can't see an axle working if it bent without some severe noise/destruction. Are you sure the body is not bent/misshaped causeing it to seem this way. You may want to check again. Another idea may be a bent wheel?? Maybe jacking up your rear and having a closer look would help diagnose this.
J Arthurs

The body is straight. My wife tells me that the wheel was also shaking, so that may be my problem. I will put on the spare and see if the problem persists. Thanks. Any other possible causes?
Napoleon

Is it possible for the rear axle to be mismounted unsquare to the body? That would move one wheel forward or behind the other.
william fox

If the leaf springs are non-symetrical front to rear, one of them may have been installed backwards. A cocked rear axle is the only thing that causes the problem you are seeing on an unbent car.
George B.

Napoleon; Jack up the rear wheels, spin them by hand and see if either wheel wobbles, it one does
put the spare on and check it. Try to get two reasonably straight wheels on the rear. Lower the jack
and bounce the car to settle the springs. Measure the height of the chrome strip from the center of
the axle on each side. Most US cars seem to sit a little lower on the left but they should be close.
Measure the distance from the inner rear fender lip to the tire on each side. One side will usually be
closer than the other, Paul Hunt can tell you which one, I don't recall. Record your measurements.
Since the MGB usually sits a little low on one side and a little off center in one direction you cannot eyeball the alignment of wheels to body with any degree of accuracy.

Move the car to a level garage floor or driveway.

Next get two jack stands or something to hold some heavy string in place, concrete blocks will
work. Sit one stand behind one rear wheel, you want it just inside the outer edge of the wheel. Tie
the string to the stand and pull the string past the front wheel. Tie the string to the stand and pull
the string tight. Move it so the the string is firm against the rear of the rear tire and is just
contacting the front of the rear tire. Move the steering wheel so the front tire is parallel to the string.
Patience, you are saving $80 per hour, your figure. Measure and record the distance between the
front and rear of the front tire and string. Keep moving the steering wheel until the two readings are
equal. Record the final readings. Without moving anything measure the distance from the center of
the front wheel to the center of the rear wheel. Record the reading It should be about 7 ft 7 in. Try to
drop a plumb to make a mark under the string and axle center of both wheels. Go through the same
steps on the other side of the car, you may need to move the steering wheel a little. Record the
readings. Roll the car away from the plumb marks, don't erase them. Make diagonal front to rear
measurements of the plumb marks. If the readings are reasonably close you car is pretty square.

If one side is longer than the other it can be caused by a flat spring on the long side and an arched
spring on the short side. The difference will be small. Let us know how you come out on this check.
The steering wheel position is an easy problem to correct. We can tell you how to correct it in another post. I've taken a lot of space to cover this check but it can be a little confusing if you've never checked
the squareness of a car before. I hope it comes out ok. Good luck, Clifton
Clifton Gordon

What would us newbies do without this great BBS resource of knowledge and experience. I just love this place! Beore I start a thread, i always check the archives, since Im sure your regulars have answered the same question at least 3x. This one I couldnt find, so thanks.

I GREATLY appreciate the suggestions, I cant wait to go home and check the problem out.

BTW, yesterday, at round 3:00 pm on a sunny CA Sunday afternoon, I found myself just driving the B, not going anywhere in particular, just driving. Has that ever happened to any of you or am I losing it!

Thanks again for the help.
Napoleon

Hehehe ... the bug has bitten - been there, done that ( most days actually). Welcome to the club!
Chris Betson

Gosh yes, I'm 73 years old and retired and have nowhere to go but I sneak out in a British car
several times per week, I can get to some good country roads with very little traffic and lots of curves within 5 miles in any direction. I'm never lost, just checking out some new short, (long) cuts. Have fun, Clifton
Clifton Gordon

Another potential cause is the spring center bolt may hace failed. This permits the axle to rotate around a vertical axis on the spring with the good bold, and will cause wheelbase variations
Greg Fast

I creeped under the right side of the car with my big head and saw that the top leaf spring, fron part, is broken. Could this cause the misalignment I have described above? If so, is it easy to fix? Thanks.
Napoleon

Yep, it sure could. You would want to replace the leaf springs anyway if one is broken. It is a fairly easy procedure and you can find very exact steps in any good manual.
J Arthurs

Short answer, Yes it is your problem. It isn't too difficult to replace a spring. It's a good idea
to replace both rear springs. You'll need a pair of springs and a spring installation kit consisting
of pads, u bolt set and shackle bushes. Your rebound straps may also need replacing. Do you
have a repair manual? If not you need to at least get a Haynes MGB repair manual. To do the
springs you need a level place to work, a floor jack, some jack stands, a bottle jack or some
other small jack and basic hand tools. I suggest for safety that you not drive the car until the
broken spring has been replaced. Driving it can do some serious damage to the car, or cause an accident. Try local book stores for the Haynes book or you can order it from Amazon.com. Get
back to us as you have additional questions, someone on the list can guide you through the
spring change process. Clifton
Clifton Gordon

I just bought a car with the same problem. The top leaf spring on one
side broke. This lets the front section of the broken leaf actually slide
forward. On mine, the break was not just a crack, it had slide about 1.25
inches from it's original position. This put my wheel 1.25 inches back in
the wheel well, as well as cocking my whole rear axle at an angle.

I ordered new springs from Victoria British at $50 US apiece. You will
definitely want two, the old ones were saggy and the ride height between
the old and new would be very noticable, you'ld be all tippy!

I went ahead and ordered new poly bushings to replace the rubber OE ones.
Another $45.

Remember not to tighten everything up till you have the wheels back on
the ground or there will be residual forces your pre-tightened bolts will
be fighting.

Cheers,
Anders
Anders Green

This thread was discussed between 22/07/2002 and 25/07/2002

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