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MG Midget and Sprite Technical - Front suspension questions

I have started looking for the clunks and rattles in my front suspension. As everyone says there is some play in the suspension due to its design from the old days of relatively open joints and grease guns. The new grease hasn't fixed the rather bad rattles I get mainly from the near side. However at the moment I have more play in the top of the off side suspension than the near side. Hey Ho as they say.
I have also been reading some of the archive and agree it would probably pay to replace the bushes (looks like they are the original rubber to me) with road going polly ones. If I do; will I need to ream anything? I know Guy wrote a thread on making a reamer so that's not a problem if I need to. But I like to keep things to a minimum if I can while still doing a good job (like not disassembling the manifolds on the head when I did the HGF, that was great advice Guy).
Its the age old I need to get my head around the planning before I start. Any outlines for checking / order of dis / assembly, things to look out for, things to get ready cos I will need them, etc.
As this is my day car (used approx. 3 of the 5 work days a week for anything between 5o and 100 miles on those days) I need to keep down time to a minimum.

Cheers, Dave
Dave Squire (1500)

Dave, if youre just replacing the bushes i dont think you have to ream anything, but you will need to get some scraping tool in where the old rubber bushes were just to scrape out the old rubber.

Ive heard mixed reports on poly bushes, its worth you doing a little bit of research via google, some people love the poly, but some hate it (like Marmite).

Those in the "for" camp say its longer lasting and a stiffer ride, Those "against" say that they tend to squeek and not worth the 10x price compared with the rubber ones.

i replaced my rear shackle bushes with poly 3 weeks ago and they have started to squeek already.
Andy Phillips (frankenfrog)

Personally I prefer the rubber ones on a road car. Also check the king pin does have any up and down movement as the top oilite bush may be worn and need the shim removed or the bush replaced
Bob Beaumont

I've tried the yellow 'fast-road' urethane suspension bushes throughout front and rear and they were OK just slightly firmer but two years later when I changed suspension I changed to Super-Flex bushes throughout front and rear and much prefer these

suspension bushes are often forgotten about and their replacement can make a big difference in their contribution to the suspension so you're quite right to consider them along with the rest of the suspension

the only squeak I can remember having was from probably the rear spring leaves but as it's disappeared with use of the car I'd forgotten about it (? perhaps cars that sit unused for periods are more prone to these types of squeaks ?, ? or perhaps they're not ?)
Nigel Atkins

Fitted polybushes... and removed them. Too harsh, and they were the "road" yellow ones from MGOC. Put new rubber ones back.

I guess you are thinking of the bushes at the inner end of the wishbone pan? No reaming, just patience needed as they can be really fiddly to fit - mainly lining it all up when trying to push the pin home. I would also replace the fulcrum pins and tabbed washers that go with them. File a lead in on one of the old pins and use as a tool to help line it all up.

Don't forget you are going to need to drop the coil springs out. Lots of advice on this and how to do it. I used the "long bolt" approach. Slow but helps reduce the potential for expensive dentistry.
G Williams (Graeme)

Careful dave

This can get really involved fast and take a while and be expensive

The fact that you said the rubber bushes are orginal puts a shiver down my spine.

Once you start... it may be a case of not being able to get out the job...start adding up wish bones, shocks, coil springs, wheel bearings rack rebuild, king pin rebuild plus tools and materials...and you can be hitting the $1000 mark for just a stock set up and a month worth of down time....make sure you got a car to use for the summer if need be

The rabbit hole is a one way trip, you cant turn around and go back once you start

Prop
Prop and the Blackhole Midget

I think the best thing to do is spend a LONG time inspecting, testing, pushing and pulling in order to identify exactly what is worn. Feel for movement between adjacent components with one finger across the join and have someone else help by applying the brakes hard to isolate wheel bearings whilst you check.

There are so many possibilities and although on an old and neglected system they may well all be worn, you can get lucky and find that some parts are OK. But its best to know before the spanner work starts, especially if you need to keep the car in usable condition with minimum down time.
Guy W

Wheel bearings? Did someone say WHEEL BEARINGS? That is tantamount to needing to hit that Report Abuse link!


When I started my font end rebuild it opened up a can of worms: bushes, fulcrum pins, snd shockers and then track rod ends and a device to set my onw track. Then wh**l b**rings and new callipers (phase 2)!

Didn't touch king pins or steering rack. It is so easy to underestimate just how much could be worn. Front end handling now transformed however.

Then you can start at the back end.
G Williams (Graeme)

Yeah. ... I did mention those demostritive little things with packed balls

But I did it in a way that it may not have been noticed like at the pharmacy...

nose spray, asprine, ** petite condums** potato chips, soda pop, local news paper....

hahaha.. it sorta just gets lost in the mix

Prop
Prop and the Blackhole Midget

If you are going to use poly bushes (and I would) use the blue Superflex ones. Most others are too hard IMO.
Mike Howlett

Greetings gents, I have been trying to get the front
suspension sorted. So far two king pins , blue poly bushes at inner end, new fulcrum pins. re built calipers. hours of worry about fitting new wheel bearings. I fitted peter may top trunion kit but
seems my rack is not standard so thats been abandoned!
Peter may supplied red poly bushes. Could I get together could I F--K. I surrender. there is nothing
orriginal about the car so I found some mk 3 cortina
units so I will put some double wish bone suspension
and coil overs. At least it will handle!!
wish me luck. Pete K
P C Knightley

your car sounds like my car in the hands of its future owner....i feel.sorry for the poor guy...hahaha

Prop
Prop and the Blackhole Midget

Just as I thought Guy; its down to hard graft again to get it right before starting to disassemble. As always I need the confirmation. Interesting about blue polly's can't say I have noticed them but will look for them now.

My experiences with motors in the 70's more or less backs up the keep it serviced and looked after approach as I never had to replace rubber components. Some of those cars did over 100,000 private driving miles. This leads me to suspect a lack of greasing is the problem. Plan therefore is to keep forcing grease in and crap out to allow the joints to move if they are going to. Should see the problems easier over the next few weeks.
Dave Squire (1500)

What does too hard mean? What's the shore hardness for one make of poly against another against rubber. Real hardness is running bronze bushes.
Daniel Stapleton

Danial...

I think it comes down to the butt squish ratio

The older you get the less butt meat you have thus the addition of more unconfortable butt squish

When your 20 ... then black poly is still to soft at 40 yellow isnt to bad, at 65 we are secteatly double folding a pillow to sit on

Prop
Prop and the Blackhole Midget

I've been folding and unfolding cushions for years and its nothing to do with comfort of the rear, all to do with ride height of the head.
Dave Squire (1500)

i take back what i said about my bushes squeeking.
Drove the car again yesterday and today and squeek has gone... maybe the polyybushes need a settling in time....
i used the blue ones from Moss BTW.
Andy Phillips (frankenfrog)

Hardness of polybushess is more to do with TRF (Teeth Rattle Factor). THe yellow MGOC bushes are sold as "road going" but it meant I could feel every bit of grit I ran over. The positive side though is that the polybushes seem to squeeze into position much easier than the rubber ones.
G Williams (Graeme)

Assuming that you have rubber pneumatic tyres on your car (reasonable assumption?)
And that they are inflated to the right pressure (moderately reasonable assumption?)

Then surely this is the main source of insulation from road harshness; the tiny by comparison, rubber fulcrum bushes must surely have a similarly tiny impact compared to the tyres.
Guy W

In which case one could conclude that whatever is in there makes no difference. It's all about stiffness or compliance or whatever. The car was just more harsh to drive. I didn't like it and having a direct comparison between new poly and new rubber I prefer the rubber. In terms of the ultimate steering and handling response I couldn't tell you which is better - I would guess the poly - but that is a lower priority to me compared with the vibration coming back up from the road.

It's a bit like servos - you love them or hate them.
G Williams (Graeme)

Graeme,
I was playing Devil's Advocate. Hoping someone would give the explanation. I don't actually deny that the type of bushes used does affect the harshness of the ride. It just seems strange that this should be so.

Actually it is maybe due to the "squishiness factor". The rubber and the poly bushes are quite squishy - you can compress them quite a lot just between finger and thumb. By comparison a fully inflated tyre is pretty rigid. Yes it flattens on the bottom in contact with the road when the car's weight is on it, but it is still pretty hard to compress - you need to put full body weight on it to make any visible difference at all.

Have I answered my own question, or is there more to this?
Guy W

I surprised Graeme found the yellow bushes so hard as when I had them, on a standard suspension, I didn't but it shows all the varying factors to bring us to our differing opinions (including personal experience and choice)

I'm used to cars with stiff suspensions but I like compliant suspensions certainly not harsh or too hard

I think as I normally only drive my car most of the time I'm more used to how it rides but I do drive other cars occasionally so do have points to compare against my car

I've always found that tyres can be a sizable factor to ride comfort and they can be very specific the make, model, size and pressure and even a permutation of those four

with the same suspension set up and settings I had to drop the damper settings to softer when I changed tyres and that wasn't enough I also had to drop the tyre pressures too otherwise the front was too harsh - only change was the tyres

the springs, dampers, ARB effect the feel of the ride and even the feel of steering can leave an impression, when I added locating end stops to my oversized ARB a lot more road surface feel was transmitted to the steering wheel
Nigel Atkins

ETA: i meant to also put

I went out in and drove an ex-track (book-a-track) Capri on the road and despite the dampers and springs being so hard that I couldn't get them to move let alone bounce by applying my weight to shove the front wing and the car sat very low to the tyres and ground

I took the car down a particular uneven road and the ride was very comfortable, more so than many altered road cars I've been in, I'd have been happy to tour in it

so a firm suspension set up doesn't have to be a hard or harsh ride

I've no idea what tyres were on on it other than wide
Nigel Atkins

I think that the hardness or otherwise of the fulcrum bushes is more to do with transmission of vibration than how firm the suspension is (springs)or how the suspension reacts to uneven surfaces (dampers)
Guy W

I had a rattly front as well, and the problem was worn out dampers. The lever bushes had gone sloppy, and were allowing excessive motion of the lever arm, accompanied by a rather heavy rattle on uneven surfaces. I'm now running a set of Peter Caldwell's finest after using Apple Hydraulics refurbs for a few years until they leaked all their oil out.

So I'd check that first. As for poly bushes, I've used the yellow ones for years and am still happy with them. I haven't had any issues with squeaking, perhaps because I lubed them with whatever kind of grease they supplied with the kits. As for a hard ride, the midget feels downright cushy compared with my '10 MINI S on runflat tires.

-:G:-
Gryf Ketcherside

with shocks and dampers I'm thinking of the general feel of the ride and with all the items one or more effects how one or more of the others reacts or interacts with one or more of the others
Nigel Atkins

Right.

-:G:-
Gryf Ketcherside

Gryf, I was beginning to think dampers as I still can't get any play in the nearside (my passenger side) and the greasing has sort of made the squeaks and small rattles diminish. More grease will be added later to push more crap out of the joints. The big jarring jolt is still there though and today it jolted the bonnet loose onto the catch. This may be enhanced by the steering rack that has no grease nipple so I also need to get grease in there. I have the strategy for that. So I need to think how to test the shocks. (apart from the usual wing push that's fine by the way). This sort of thing is new to me so its a case of trying to work out how to get the correct leverage for the play in the arms.
Dave Squire (1500)

I am reluctant to mention this but....

The most significant contribution to "rattle" on the front end and steering was too much play in the (!) front wheel bearings.

New shockers plus the bushes eliminated understeer caused by wandering out through bounce on corners, but the rattle......
G Williams (Graeme)

Dave,
rattle could be from so many things but the jolt sounds much more serious, if the lever arms are loose a pry bar of some sort I'd have thought would show it

I think meeting up with other Spridgets owners in theirs and your car might help pin this down more than forums, taking a knowledge and/or experienced person on the subject in your car might help, as would you going out in a standard 1500 in good mechanical condition as you can get an idea of the 'normal/usual' 1500 noises
Nigel Atkins

Andy....

try retorqueing the bolts at the leaf springs where they attach to the axle... this Is a very common area of squeeking and travels thur out the car easily...not sure why they get loose but they do.

Prop
Prop and the Blackhole Midget

Dave... have you tried the "shake it" no one has mentioned .. so we may be just assuming

Jack up the wheel off the ground grab tire it at 9:00 and 3:00 oclock and shake it hard...if there us play, you have issues with the steering.rack

Next grab the tire at 12:00 and 6:00 and give that a harsh shake...there is play its... (oh god please forgive me) ...""gulp"" ... wheel b**rings

That said get some darts and a copy of the expolded diagram of the suspension and just throw some darts wrapped in $100 dollars bills at It.

Prop
Prop and the Blackhole Midget

Dave,
Eeryone will throw random suggestions at you! The suggestion of placing a finger across two surfaces and feeling for the movement is because it is surprising how little slack will translate into knocks, bumps and rattles on the road. So much so that simply looking at the joint it may not show up, especially when you are also moving around yourself as you push and lever on each one. Do the tests with the wheel raised - spring and under compression, and with the jacks under the chassis so0 that the suspension is extended.

And here's my random suggestion for a heavy jarring jolt from the front: - check that the 3 bolts securing the damper to the car are tight. Mine seemed to unwind themselves a bit quite regularly until I used locktight on them.
Guy W

I thought the damper being loose on its nuts and bolts had been covered but I was wrong, so many threads

I could imagine doing your tests and getting a blood blister as I seem to almost always do when using the large scissors :)
Nigel Atkins

This thread was discussed between 13/05/2013 and 15/05/2013

MG Midget and Sprite Technical index

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