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MG MGB Technical - 72 MGB Frnt Suspension - Help!

I have a 1972 mgb roadster.
The front Left suspension has wedges in the coils and the bushings appear to be missing in several areas and around the wishbone points.
Is this something for an ameture and manual? The service manual don't give a lot of the details and issues to watch for. Removing coil et and how to. Is this dangerous and are replacing the parts easy enough to do? Thanks in advance for your help. Best regards,
Doug
DT Toms

Doug. See the other thread current on this topic. Also, check out the archives. Yes, this is something the hobbyist can do, at least, many of us have done it successfully and you should be able to do so too. Les
Les Bengtson

I have ready many of the archives.
Here's my take.
Strap the coil spring with like a perforated metal strapping and secure to something substaintial.
Using floor jack, take tension off spring and start dismantling.

Questions:
Sounds like for ametuer, it might be best to order all new parts if I have the money so as not to have to use jewler saws et to get out old bearings or seals?

How much should I expect to pay for complete rebuild per side from a shop?

Is there any better self do-it manuals like "VW's for Dummies?" The shop manual doesn't tell the ametuer all the tricks, just says stuff like remove king pin, remove coil spring. UGH.

That's for your time and effort in answering my questions.

Best regards,
Doug
DT Toms

Doug,

The factory work shop manual helps a little, but there are some things that you have to learn from doing the job yourself. This BBS has provided many helpful tricks and hints that are not provdided in any manual.

If you need any help and are close to Columbus, feel free to give me a call, at 614-218-7377 as I rebuilt the suspension on my '73 B about 2 years ago.

Zach
Zach Dorsch

It's actually not that hard. And much has been made about the strapping, etc, but here's something that's been working for me (Les and others may cringe) as I've been doing a lot of spring swapping recently.

Jack the car up under the front cross member so the wheels hang. Support the car with jack stands on both sides - the engine bay frame rails are a nice choice. Remove wheels (loosening the nuts before lifting is a good idea). The springs are now almost at full extension anyway. This is probably a good time to either remove the calipers or remove the hoses, depending on whether you want to bleed the brakes. Regardless, don't put any weight onthe brake lines.

place a second trolley jack under the lower king pin mount, and remove the upper king pin bolt and the bolt holding the sway bar and down link together. The lower arm is essentially free at this point, and if you remove the jack, you may be able to get the springs in and out as it, or you may need to remove the rear and front interior bolts holding th pan to the A-arms. Then the pan swings clear on the downlink mount. once you get to reassembly, place the sping in the tower, raise the outer end of the A-arm with the kingpin installed, and just jack it back up to match the shock arm. Then do the sway bar back up.

I've also done it by just removing the 3 pan bolts and swinging the pan clear, but I wouldn't necessarily recommend it in retrospect. Reassembly this way is a pain.

In my limited realm of car repair, this doesn't really stirke me as terribly dangerous, so long as you take the standard precautions re: working under a vehicle and pay attention.

Steve
Steve Aichele

Steve et.al.,
Thanks for all the great feed back.
Sounds like changing the springs I can manage.
Hopefully once I get it apart, the bushings et. will be manageable.

The King Pin bushings sound like they take special reaming tools.

I am printing this out now for my great adventure.

Thanks again folks.

Best regards,
Doug
DT Toms

"The King Pin bushings sound like they take special reaming tools. "

They do. And the reamer costs $$$ and you probably won't use it but once.

Here's my advice. Get completely rebuilt and assembled kingpins and slap them on. For the $50 to $100 xtra it costs, rebuilding them yourself is going to cost more in time and money.

Luigi

Luigi

Rebuilt kingpins are available from most regular MG parts sources. I've had good luck with the Proper MG up in Maine.

Sometimes a local MG club will have a kingpin reamer available for loan...then, you can do your rebuild as a tech session for the local club.

Just an idea.

rick
rick ingram

The method I used was very simple if a little nervous making.

Put floor jack under pivot at x-member.
Remove four bolts holding pivot pin to x-member.
Lower floor jack.
Using a second jack, lift car until it rises off first jack.
Wrestle spring out.

Installation was more or less the reverse of removal. It was a little trying to get the bolts to line up for the pivot pin but not too difficult.

Remember to not tighten the pivot bush nuts (on the ends of the pin) until the full weight of the car is back on the ground (tight fit for me!).

Mike!
mike!

The easiest way bar none, is to put tension into the spring by placing the jack directly in the center of the spring underneath the spring pan. With the jack under the pane, undo the 3 spring pan bolts and the sway bar link. Once thats done, lower the jack and the spring comes with it. Super easy and safe and takes no time at all
Jarrod

Didn't have success doing that. For a start the anti-roll bar bolt was siezed in the A-arm, and even when that was free it was impossible to keep the spring pan level such that all four bolt holes were aligned, either removing or replacing. This meant having the juggle the jack and pan up and down to get each bolt in, which tended to chew the ones that were already in. Far easier for me to remove the bottom bolt through the A-arms and axle casting. And BTW the car must be securely supported and not just on jacks before starting either method.
Paul Hunt

Completely agree with Paul and Steve. Block the car just as Steve says then either remove the bottom swivel bolt or the top one. For me the top one is easier as it can be seen better but to trying to juggle the spring loaded spring pan on the jack is a no..no, darned awkward and not nearly so safe.
Iain MacKintosh

Perhaps I was just lucky because it took me no more than 10 minutes/ side to remove the springs this method
Jarrod

One small trick if you think you might be doing this more than once - put the bolts in from the inside out. Then a year or two later when you're trying to replace them, you can hit them with a drift to pop them out. Hitting them from the underside is tight at best, and potentially exposes you to some spring energy.

Steve Aichele

That outer bolt can be a pain to remove and you also have the whole corner in the air. Pulling the bolts for the inner pivot means the wheel is still on the ground so if all goes "POOF" you are more likely to get out uninjured.

Do it the way you see fit, obviously there isn't any consensus of opinion.

I just wish one of the several coil spring compressors I have tried would work... Guess I'll have to make one.

Mike!
mike!

I have the entire front suspension out of the car for restoration. I borrowed a spring compressor from Autozone. It was just long enough to fit under the spring pan and over the lever arm of the shock. I used both compressors, one on each side of the spring pan.

This worked fine. However, I don't think the clamps on the compressor provided an entirely secure grip by the looks of the setup. I suppose you could easily make your own purpose-built compressor if you think about how to design the clamp.

Next step is to install the new springs. Have never done this. Thinking about the trolley jack and chain method.

Tom
Tom Custer

Tom. I used two pair of vise grip pliers--one on either side of the springs, to compress the springs. It did not take much to allow them to fit, but I had the engine in. I have been wondering about simply cutting two pieces of steel bar stock, say 3/8" by 1" about seven inches long. Drill a couple of holes near the end and use some bolts to tie the two pieces together. Then, install them between a couple of coils, tighten the nuts to draw the two pieces of steel together and the spring coils trapped between the two pieces are compressed. This should allow the springs to be inserted whether the engine is in or out. Have not tried this yet, but similar systems have worked before. Les
Les Bengtson

Les, that's an intersting concept. I wonder if the 3/8 thickness of the metal bars would be enough to prevent bending of the bars and loss of compression while clamping? Seems like it should work.

Regards,
Tom
Tom Custer

Hello again,
A little confused still.
Some seem to use different names to refer to same parts.

Steve's method seems pretty clear.

Get the car on stands and remove caliper. Ok
Place a 2nd trolley jack under the kin pin mount.

Is there a 1st jack under the spring pan?
The kin pin mount, is this just at the bottom of
the kin pin?

Remove the upper kin pin bolt. ok, nut at top of kin
pin?

Remove the bolt holding the sway bar and down link together? ok, I only see 1 bolt in the diagram that
that could be.

The lower arm is now free?
Does this mean the lower arms that the spring pan
is attached to? It will swivel on the wishbone
pivot located nearer the engine side?

Lower the jack under the spring or the kin pin mount?
Then the spring comes out.

I know there is bushings missing in the lower part of the wishbone both on the pivot side near the engine and the side nearer the wheel.

These can be taken out and easily replaced at this point? Anything tricky?

I also noticed on 1 side that the spring pan only has 2 bolts nearest the engine. The side nearest the wheel, the bolts connecting the pan to the wishbone are missing and the pan is below the wishbone arms and holes not aligned.

I guess I should jack that pan up and try to get
those bolts in first so spring don't pop out or
something. In some of the diagrams, it looks like
4 bolts should be connecting pan to wishbone arms?

How do I evaluate the shape of other bushings and components? How do I know if I need upper bushings, new kin pin et.

I was told by a shop, the the lower bushings and spring would be $250 per side if I supplied parts. He said upper bushings are much harder to get out.

If the bushings on both sides of the wishbone are replaced,along with coil spring (that has 2 helpers wedged in worse side), will this make a difference in clunking, or does clunking mean I have more than lower bushings and coil springs needing replacing?

I don't see any leaking around shocks.

Thanks for your patience and helping this ameture.

Doug
DT Toms

Oh,
I forgot. I was also reading the article on steering and suspension.

He refers to similar methid and references
Pivot stub axel.
Is that the wishbone pivot?

He mentions lower trunnion bolt?
Is this the bolt that runs through the wishbone arms nearest the wheel?

Thanks,
Doug
DT Toms

I'm not entirely sure I'm using all these terms correctly, so here's a brief declaration:

Stub axle - round bit the hub actually rotates on
Kingpin - the vertical piece running between the shock arm and the outside lower A-arm.
Trunion bolts - bolts at the upper and lower of the kingpin.

The use of the term '2nd jack' is because I usually lift with one under the center of the crossmamber, then leave it supporting some of the engine weight (with stands under the frme rails near firewall). Thus any other lifting is with a second jack.

That second jack goes under the lower trunion bolt, and lifts the weight of the hub and will start to compress the coil spring (just enough that you aren't fighting it when removing the upper trunion bolt and sway bar link).

Those two bolts are the only things holding the lower A-arm up. So when you lower the '2nd jack', the A-arm, the hub, and pan all pivot downward on the inner A-arm mounts. You should be able to get the springs out now. No jack under the pan at all.

If you're actually missing bushings, it probably clunks somthing fierce. You probably want to check that the holes in the A-arms are still round, not oval.

As to the spring pan bolts, there should be 3 bolts (5/16ths' I think). The outside front of the A-Arm is the link for the swaybar (sounds like the whole swaybar might be missing). It'll be a piece of cake to put the new bolts in once the springs are out, so as long as you aren't driving it, I wouldn't worry about getting the outside of the pan back in line before disassembly.

As to that price, I'm not sure what he was quoting. Tha A-arm and trunnion bolt bushings should cost almost nothing (most people do them at home). Reaming new kingpin bushings takes some skill and special tools, but provided the parts ought to be more in the neighborhood of $50/side.

Steve

Steve Aichele

Steve,
Thanks so much for helping me clarify.
The A-Arm is the wishbone? The pieces that hold the bottom spring pan?

Also, I think I am missing a complete sway bar. I started to say that, but was embaressed to say I didn't know. But the best I can tell, the sway bar IS missing.

I noticed in the catalog, that original sway bars are no longer available, but you can buy I think 3/4"? Is this sway bar a good thing to have and do you have any experience with the heavier replacement?

This has been very helpful. I may be quite new at this, but hopefully I explain my ignorance clear enough so you all can steer me right.

Much appreciated,

Doug
DT Toms

Doug,
a used original sway bar should be easy to find and cheap. Buy the links (from sway bar to A-arm) new, they wear.
Also, buy every rubber part of the front suspension.
This is the best opportunity you could have and it sound as if your car hasn't had a lot of maintenance done. This shouldn't cost too much and your car will be much more fun to use.
Check the archives for more info.
HTH,
Rufus
Rufus Pool

Look, you need to get the suspension in good condition, not only to enjoy it, but so you don't find yourself wondering why all the froggies are hopping on the ceiling as you land in the ditch.

Regardless of the method employed (I happen to think mine is the easiest but, there you go), you need to release the stored energy in the spring in a controlled manner. It doesn't appear to be very large but it will HURT you.
Missing bolts/sway bar sounds like someone before you tried to get it out and was either balked by stubborn bolts or someone who noticed what he was doing and stopped him before he hurt himself (suspect the former).

My two cents worth:
Get V-8 bushes for the lower wishbone pivot (inner end) unless you plan on aggressive driving then sacrificing a little comfort for additional control would be acceptable and Urethane or Nylon would be the way to go.
Get the front rebuild kit from any reputible supplier that has the pre-installed and reamed king-pin bushes (on an exchange basis... you may need to pony up a little extra cash for the deposit and/or if yours are not rebuildable). Again, aggressive driving opt for the urethane bits.
Now you can do it yourself. If the suspension cycles and the wheels turn (lefty-righty) without undue effort then it sould all come apart OK. You may find some surprises, but a big hammer (wisely weilded) often puts surprises in their place as well.
Ja, get the big bar and get the adjustable end-link kit too. I use the hardest grommets and the solid link spacers for auto-x and was not upset by the ride on pavement, but you can let it have more or less compliance to suit your needs.

Using my method, you detach the swaybar link and then the the wishbone pivot from the x-member and lower it on the jack and then jack up the car off it to release the energy. Once done you go back and dis-assemble the front suspension. The drawback is that you can only do one side at a time. The benefit is you can only mess up one side at a time!

Take your time, buy a Bentley manual, and watch your fingers!

Mike!
mike!

Mike,
You and others have been most helpful.
I am convinced to have a go at it.
Like you said, worse thing is I can't figure it out completely and I have it towed and fixed.

I guess I'll take it apart before ordering the complete kits et to see if the arms or pans are ovalized.

I'll just take my time, patience and hopefully get this girl in good shape for next spring.

Thanks so much for your kindness and time.

Best regards,
Doug
DT Toms

This thread was discussed between 21/09/2004 and 28/09/2004

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