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MG MGB Technical - Suspension Re-bushing

Now that my recently restored 1978 B (with 90K clicks)is going in to "winter hibernation" I am planning to do some DIY work to improve the car for next season (this would be summer). I was thinking about the various suspension bushings and which ones to replace first (and easiest). I just read a thread on the difficulties of extricating the Rear-End Sway bar bushes. Hmmmm !! At present I don't seem to have any apparent signs (or noises) that indicate that replacement is critical. Car is level (!!) springs and shocks OK. Should I concentrate on other things (and there are more on my list)than spend time on the bushes if "they ain't broke".
Looking forward to reading any suggestions or valuable comments from the "knowledge team".
Richard
R.M. Standish

R.M.-
Look at the rubber bushings in your suspension system. Are they dry-rotted? See any signs of cracking? If so, they need to be replaced. Firmer bushings, such as those made from nylon, will reduce compressibility in the suspension component mounting points and make small steering inputs result in correspondingly small reactions in the steering. In other words, the steering will become more precise, but the greater reactivity will also demand that you pay closer attention to what you're doing. Unfortunately, because they're harder, you will feel more vibration emanating from the suspension, hear more road noise, and your hands will feel smaller pavement imperfections through the steering wheel. Hit a big pothole and you'll know it! Even worse, the greater transmission of these forces means that associated load-bearing components (Steering rack and column components, tie rods, balljoints, kingpins, swivel axle bushings, dampers, etc.) will wear more quickly. Hard bushings are also not only unnecessary for either the mountings or the attachment points of Stabilizer Bars, Panhard Rod ends, and Antitramp Bars as they offer no benefit in handling, but are actually undesirable as they will fail to damp out vibration and road shock. In reality, there are better options for increasing steering response while avoiding most of these drawbacks.
This is not to say that you should resign yourself to the use of rubber bushings. Rubber bushings wear rapidly and rot, Polyurethane bushings take a long time to wear and never rot. Sadly, almost all of the aftermarket suppliers in the USA offer only the harder varieties, being either of the "Racing & Competition" or of the "Fast Road & Rally" type. Some of these bushings are real "bargain basement" items in terms of their quality. In my opinion, Superflex over in the UK makes the best, and the price is quite reasonable for the quality of their product. They don't injection mold them (a sure sign of a cheapo bushing), they start life as a solid rod that actually precision machined to size and shape on computerized machines. As a result they will slip-fit into place. This is not often the case with molded bushings. Sometimes you have to pound them into place with a mallet, which will result in their bores being distorted or compressed, which in turn will cause them to squeak. Superflex bushings are self-lubricating once installed. They even include stainless steel sleeves so that rust can't abrade them. If you want to purchase a softer set (like rubber) for use in a daily driver, go to http://www.racecar.co.uk/superflex/ and specify 80 Shore-A bushing material for the A-arm (wishbone) bushings and 90 Shore-A bushing material when you order the trunnion, leaf spring, and stabilizer bar bushings. Superflex makes bushings for 7/8", 3/4", 11/16", 5/8", and 9/16" stabilizer bars. I would recommend 70 Shore-A material for the crossmember pads.
Steve S.

Steve. That was a really good answer. Thanks. You have covered all of the points that have been made to me over the years about the different materials and made some good, solid recommendations. Since this is something I may well be doing this winter, I appreciate your covering it in depth. Les
Les Bengtson

Let me add my thanks also to Steve S.

Following the advice given I have looked at the website for Superflex and will now completely 'Superflex' the 66 B roadster that I am 'nut and bolt' restoring.

Only yesterday I read your advice regarding the replacement of the rear leaf springs... simple sense yet again.

As a reader, learner, more than a contributer I really appreciate this BBS and the generosity of those contributors who probably learned about these cars without such a network of assistance.

Steve S. ..... Have you ever thought about collecting all of your BBS tips into a book? "Practical mgb restoration tips"... or something like that? Or have you heard that before?

Best regards,

Angus
Angus

Steve:
Thank you very much for the most thorough advice and recommendations. Don't think much more could be said as you pretty well covered this in depth. Going to order the SuperFlex stuff and I'll let you know how things turn out.
Glad to see my questions gave opportunity to others to benefited from your answer and practical experience.

Angus.... I have begun to copy and assemble many pieces of advice from the BBS into my own Practical Repair Binder. I have assembled several sections already such as: wiring, controls and linkage, dash instruments, carburation (I have a 32/36 DGV WEBER, BTW).
This is a great place to learn and share. I hope to soon be able to contribute in exchange for the kind support.
Best regards Steve.
Richard
R.M. Standish

Steve, whilst you are on the subject, can you say a little about the Sway Bar End Link bushings.

Mine are a little rusty on the metal, but will polish up. However, I can't decide if the bushes need replacing.

30K miles, and the horrendous cost of $60 x 2 total $120 looks nasty.

I asked the question on the Sway Bar thread and Jon Guinea, Oakland, CA, kindly offered http://www.suspension.com/mgb.htm

Look forward to your comments on the practicality, and advisability of proceeding down this route.
Fred

FYI-

The dealer in the U.S. for Superflex is www.carorphanage.com. They are not cheap, but may be less expensive than ordering from the UK.

Sam
Sam Sullivan

Les-
Thanks. Coming from someone of your stature in the MG community, that's a real compliment.

Angus-
You're welcome. It's nice to be thanked. I've written a series of articles. They're under continual development, being constantly improved and added to. I give then away for free.

Richard-
You're welcome. I'm sure that you'll be well satisfied with the results because I've set my own car up the same way. Look forward to hearing about the improvements when you get the car on the road.

Fred-
All rear leaf spring bushings should be in a good state if you want the car to handle well. They help to prevent the rear leaf springs from swaying laterally and ruining the front/rear wheel alignment.
Burning out the bushings with a torch will make a nasty mess on the bore of the mount. It's hard to believe that yours could have seriously deteriorated in just 30,000 miles unless they're over five or six years old. How old are they? Can you see any cracking in the material? The main purpose of the bushing material in this case is to dampen vibration coming from the rear axle assembly. It's the stabilizer bar itself that reduces body roll and assists in keeping the rear axle centered along the longitudinal axis of the car. If there's no visible sign of deterioration or ovaling of the bore of the bushings themselves, just clean the rust off of the mounting body and repaint them. When you screw them back on to the ends of the stabilizer bar, be sure to use antisieze compound on the threads. Although Superflex doesn't make these bushings, Energy Suspension does. Unfortunately, I don't know what their Shore Hardness is.
Steve S.

Steve, all bushes are the original, 1980 vintage.

All bushes are being replaced, however I have only just realized that I also need to do something about those Sway Bar bushes.

To my horror, I found that they were $60 each to buy, the complete link, and Moss certainly don't supply separate bushes.

I'm not 100% sure about their condition, depending on the time of day they either look OK, or, I am almost sure I can detect a tiny split in one of them.

Really I'm not sure, however, if I were able to buy replacement bushes for a few dollars, I wouldn't hesitate, but at a total cost of over $120, I can think of other things on the MG to spend that money on.

Should I get the old bushes out and get new ones from these third party sources.
Fred

This thread was discussed between 12/11/2002 and 18/11/2002

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