Morris Minor Owners Club

Hi all.

I keep hearing stories of the front wheels of Minor's dropping off, I think because of the thread on the top trunion or something? Is this true, and if so how likely is it to happen? I tend to drive quite spiritedly, but do ensure everything is greased up and oiled reguarly.

If there is anything I can do thats likely to prevent me loosing a wheel, or you could explain what actually happens so I can keep an eye on the offending part, that would be great!

Thanks.

i believe the problem is more that the wheel collapses in as opposes to falls off.. about to be corrected on that though.

The problem normally occurs at slow speeds as you turn a corner I believe as this is when you put greatest strain on the trunnions.. so by keeping everything oiled and greased will ensure that you do not have the problem

Wheels fall off??

You are right about the trunnion, but it is the bottom thread. What happens is, if it's not greased and maintained as per manual, eventually the thread will wear and pull off the trunnion. An annual MOT should spot this before it gets this bad though. Golden rule... grease regulary, if you feel any play get it sorted. It will never come away then. ;)

Hey.. Charlie got there first...

Cool, thanks. Its just passed an MOT a few months back but will check for play and regrease tomorrow! Still, its all good fun!

Yes, it does happen! I know because I once saw a Moggie by the side of the road with the wheel sticking out oddly and the front end of the car down.

You can easily check periodically by putting the car on a stand under a chassis point, with the tyre about three inches off the ground, and placing a long bar ( five or six feet) about a foot under the wheel on full lock (for visibility) and lifting it upwards. Any play between the trunnions and the kingpin can be seen as you move the bar GENTLY up and down. Best to place something solid on the ground under the end of the bar you are holding, to make sure your fingers can't get mashed if the car comes off the stand accidentally and the bar gets forced downwards. Better still, wrap a piece of rope around the lifting end of the bar, and hold this to lift the bar, but not putting your hand in the loop.

Oh, fuss and bother! Just be careful!

Mick_Anik wrote:Oh, fuss and bother! Just be careful!

I'll give this a try over the weekend, although body restoration is still top of the agenda!

It's happened to me twice, back in the early days of having the car, before I got wise to the problem. The first time we just replaced the bottom trunnion, the second we replaced both front kingpins & top & bottom trunnions, plus the steering rod arms & track rod ends for good measure. Each time it happened at low speed, as mentioned earlier, on a corner.

That was back in the late 80's. Since then I have greased the front suspension every 1000 miles almost without fail. The car has now done ~50k miles without a problem. So the lesson is, assuming the kingpins and trunnions are ok in the first place, regular greasing will pretty much eliminate the problem. It's sheer lack of maintenance that is the primary cause.

A tip on greasing it. There are grease nipples on the top and bottom trunnions and on the track rod ends, so 3 points each side. It's best to have the front of the car off the ground and the wheels removed to do this job. The grease flows better into the trunnions and the threads with the weight off the car, besides, it's a damn sight easier to get at with the wheel removed!

cheers,
N

It happened to my previous morris when I was a student (and therefore didn't know better). I pulled out of a petrol station and as I went over the kerb the trunnion popped out of the thread and the car was left with the wheel in an odd position and all the weight going through the wing. I thought it was the top joint that came out, but it was a long time ago, I could be wrong. Replaced it with one from a scrap yard and motored on.

When I bought my blue minor the drivers side front trunnion was held in place with a thick rope between bottom wishbone and shock absorber and a big chisel to tension it!! Needless to say the first job when I got it home, on a trailer was, to replace both kingpins and trunnions. I reckon its done about 60000 miles since then witout any trouble.

sorry i would like to prevent this front happening to minty and have no experience in doing so.

any pictures of the top and bottom trunnions? so that i can grease them and check for play.
Thanks

see here http://www.auto-part.com/britCatalogs/m ... =1&page=15

good diagram kennatt.
h20 - you need to locate the two grease points numbered 116, and a third grease point the same shape which is not shown

Blimey, I'd neep a good map and a stiff drink before I tried navigating all that lot!

I think Minors got a reputation for this when they went through the banger phase. I remember seeing Minors down at one corner during the 1970s. This was a reflection on age and lack of maintenance, rather than anything else (Though a thread is not the best bearing surface).

My MOT station (http://www.sirhowygarage.co.uk/3742/sirhowygarage.htm), although they have moved into selling nearly news, have a number of old cars and have experience of old cars. They said that if greased properly and regularly, it isn't a problem. Moreover any suspension about to fail would be very loose prior to the collapse. If you grease regularly, you would feel excess play when the front wheels are jacked up.

If you fit the larger 9" Wolseley front drum brakes - the backplates incorporate a 'dip' that encompasses the king pin base - and it CAN'T come off! It can be very loose - but it cannot fall off. Similarly - if you add on extra telscopic front dampers - if these are the correct length they too will prevent the suspension collapsing - provided they are fixed (and most are) to the lower suspension arm !

I always though that this problem happened much more often on the Marina, perhaps they were bangers for longer whereas Moggies went from the banger stage to being better cared for much sooner?

When I lost my front wheel it wasn't the trunnion it was the outer suspension arm that closes around the lower trunnion. It sheered through and I lost the wheel.

Again I must have been doing >20 mph and coming into a roundabout.

No amount of grease would have prevented that it just went on a fault in the steel.

StaffsMoggie wrote:I always though that this problem happened much more often on the Marina

Am I right in thinking that the trunnions and kingpins on the Marinas were made of a different, harder grade of metal than on the Minors? Therefore it was less of a problem on the Marinas?

From bmcecosse:

If you fit the larger 9" Wolseley front drum brakes - the backplates incorporate a 'dip' that encompasses the king pin base - and it CAN'T come off!

Not sure what you mean exactly here - I thought I had it visualised, but then started thinking about how you'd get the backplate off (or on, in the the first place) if it were somehow wrapped around the 'kingpin base'.....and here's a phrase I've not heard before. Clarification would be most welcome.

Further, could a standard Morris backplate be modified by welding something similar to it - a "just in case, worst-case scenario" operation?

Maybe we could go into this a bit......we are dealing with a system that regularly saves your own life and the lives of others, by not coming apart unexpectedly.