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MGB Front suspension rebuild is next

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drooartz

drooartz

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I suppose it is a truism that if you own a car long enough, eventually you'll have to work on every bit of it. I've had my B since 2011, and haven't done anything to the front suspension other than maintenance. That seems to be ending.

Was under the car today doing my usual spring maintenance (God Bless a lift!) and noticed that the seals on the front suspension -- lower trunnions? -- are shot. L side was just dangling and crumbled away, and the R side is looking pretty tired. So now I get to dig in and do at least a partial front suspension rebuild.

My question for the assembled minds is this: what is reasonable to do here? Is this just a quick project to replace what's obvious, or am I pulling the front crossmember to rebuild the whole shebang. Thoughts?

I'd rather not have the car off the road for long, but the Morris is running great so it can take the time it will take. Would love to hear your thoughts.

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I would do it all and do it right - If the Midget is anything to go by it isn't a huge job.
 
I'd say dropping the crossmember may be a bit of overkill. Unless the kingpin bushings have been neglected (lacking regular grease sessions) and need replacing, it's a fairly straightforward R&R of the seals and bushings in the damper arms and lower trunnion. And look for wear in the lower a-arm holes where the through bolt fits. Have seen MANY trashed due to lubrication neglect. Get the poly bushings ahead of time for the a-arms too, they make a big difference in handling.

Is there a sway-bar on yours? If you want a real reduction in body roll at the front-end, the bar used on the MGB-GT makes a difference as well. It's a larger diameter than the roadsters were fitted with.
 
Thanks for the thoughts, Doc. I've done my best to keep things greased over the years, but the suspension is something I've not messed with since I bought the car in 2011. I'll try and get at least one side somewhat apart this week and will let y'all know what I find.

I'd rather just do bushings and seals if I can, as I don't want the car off the road for too long.

Poly bushings all around?
 
drooartz said:
Poly bushings all around?
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We did that to a couple customers' cars and it convinced me to put them on our own B. Bit more solid in terms of ride but a nicer more "crisp" reaction to driver input. If you were just going out on sunny Sundays for ice cream it wouldn't make much difference. But "spirited" driving makes it apparent you've made a good modification. (y)

It looks like you've a sway-bar already, if you want a bit more roll stiffness after you've got all else in place, the B-GT bar is the way to go. The front-end can "wash out" at traction limits a bit quicker, but my guess is you won't try to find that on open roads! ;)
 
As far as I can tell the car has a 7/8" sway bar (.875 on my caliper) in the front already. Pretty sure it has a rear bar as well. Keep in mind that my car is a '70 but is a UK home market car, so some details are a bit different than what was offered in the US.

I got the car on the lift and pulled off the front wheels. Looking at things and at my manual, it looks like I'll need to pull:

Brake caliper
Hub/disc/backing plate (?)
Tie rod end
Swaybar end link
Coil spring

Then I can get down to business with replacing the bushings. Will go poly all around. I'll make sure to look at the A-arms and make sure all is well before I order up the parts.

Does this seem about right?

My Moss wish list of parts I may need
 
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Looks like you have the lists well thought out. The sway-bar bushes are a PITA without a press of some sort, BTW. A couple appropriate diameter sockets and a BIG C-clamp work tho.

The undercarriage looks pretty clean but(!) wire brush all the exposed threads 'n nuts while dry anyway, then apply weasel pi$$ to all those and wait for it to penetrate. You will want to work clean, so a couple good size metal cookie sheets & paper towels under where you apply penetrant will protect the paint on your lift. It may be the springs won't need a lot of compression with a tool to remove them with the help of a floor jack under the platforms, slowly released. But I'd recommend some sort of spring compressor just in case. Those things can pack a wallop if they have any energy stored... respect potential energy! And it makes reassembly a bit less frustrating.

Only question will be the condition of the kingpin bushes. A thorough cleaning and refitting pins with oil in the swivel will tell you if there's excess play. I fit the bushings and ream to size (38&39 in the illustrations) but that can be tricky without good tooling (the special BMC ream or a way of keeping individual ones aligned axially). That'll be a "wait-n-see" job tho.

Good time to clean 'n paint the back-plates too.
 
Thanks, Doc. Was thinking about picking up a spring compressor. For the Sprite I have a home-made properly size bit of allthread that works to release the spring pan, but the B setup is different. I probably should just have good spring compressor anyways, will have to do some research.

I was wondering about the kingpins, I don't have any history on the front suspension, so no idea when they might last have been replaced or worked on. I certainly haven't had them apart. Guess we'll see once I have things disassembled. Hoping to get to one of the sides later this week.
 
An "official" spring compressor wouldn't hurt to have on-hand. I too have the all-thread versions in my box, and some "specialized" ones home made to fit the Lotus struts 'n springs. It tends to be "whatever works" with our cars. Hard to find a one-size-fits-all tool. Most are made to use on Chevy coils. o_O
 
Basic parts are ordered. Got all the bushings and the lower trunnion kits. I'll hold off on ordering the spring pans until I can at least get one side apart and see how the metal is. Easy enough to order later, but at least the bushings will be inbound.
 
Next question: I've not tested them, but is it safe to assume the front shocks are fairly shot? I've not touched them since I bought the car in 2011.
 
Check fluid level and look for evidence of leakage at the arms' pivot points. One way to check 'em in place is once they're disconnected from the top of the kingpin, check for any "freeplay" up and down. If there is any of that send 'em to Peter. If they resist movement through the arc, leave 'em be.

Just thought of another item, the bracketed rubber bump-stop thingies that limit full droop of the damper arms.
 
drooartz said:
Next question: I've not tested them, but is it safe to assume the front shocks are fairly shot? I've not touched them since I bought the car in 2011.
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While it is apart I would do the shocks. I replaced mine a couple of years ago and it really changed the car (and I have rubber bushings) - there are a couple of things that I 'didn't do' at the time - oil pump and shocks are two - that I should have just done when everything was apart and finally had to go back to do and then kicked myself for not doing it the first time.
 
Just added the bump stops (and decided to just get the wishbones and spring pans). Kudos to Moss, they had already packed up my initial order, but gave me free shipping on the extra items I added in today. Excellent customer service.

Going to order some rebuilt shocks from Peter C as well. That will give me a full rebuild of the front end. Once it's all apart, I'll need some help figuring out if the kingpins are still in good shape. More to follow, hoping to get one side disassembled tonight if all goes well.
 
Probably the better way to do the work, then you know all is taken care of all at once.

I was considering the cost. The pans are likely still good and if the shocks are working, they could be dealt with if they wear out later. But that involves more work.
 
DrEntropy said:
Probably the better way to do the work, then you know all is taken care of all at once.

I was considering the cost. The pans are likely still good and if the shocks are working, they could be dealt with if they wear out later. But that involves more work.
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I was balancing that as well, but I'm alway guilty of the "just do it while in there" mentality. Besides, I just sold my motorcycle so there's a little funding in the kitty (after I pay back the family for the guitar I just bought).
 
Mickey Richaud said:
Do tell! What'd ya get?
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Collings D1A. I seem to get a new guitar every 14 years, so I guess it was time. Was at my local shop trying out some really nice guitars, played almost everything they had just trying to get a feel for what the next level is like. Kept coming back to this specific guitar every time. Breathlessly expensive, but sounds so good so I bought it on the spot.

The guitar at least makes me some money, so it will earn its keep.

This is the pic I took at the store to text to my wife (the price was still visible). She's a keeper, her reply was "if it's the one, get it." So I did.

collingsd1a.jpg
 
OOOOHHH!! Collings - great guitars! I know you're happy with that one!
 
drooartz said:
Collings D1A. I seem to get a new guitar every 14 years, so I guess it was time. Was at my local shop trying out some really nice guitars, played almost everything they had just trying to get a feel for what the next level is like. Kept coming back to this specific guitar every time. Breathlessly expensive, but sounds so good so I bought it on the spot.

The guitar at least makes me some money, so it will earn its keep.

This is the pic I took at the store to text to my wife (the price was still visible). She's a keeper, her reply was "if it's the one, get it." So I did.

View attachment 87931
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A Triumph TR-3 owner over in Noblesville Indiana owns/runs a shop called Center Stage Vintage Guitars. Seem to go together.
 
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