Part rotten underfloor cross member - short term fix?

[mattinhertford]

Hi all,

This is probably a silly question but....

One side of my underfloor crossmember is quite rotten, see photo. I don't really have the funds for welding this year, and learning to weld is on my wish list for next year.....so....shall i just leave this section as is, or should i cut it off (just xthe rusted part) and clean the area to stop the rust spreading?......or is it structurally vital for floor support so should really be left on?

[frame][/frame]

Thanks

Matt

[panky]

It's holding one end of your torsion bar in place, serious problem I'm afraid. You can replace one half of it but I suspect the other side isn't far behind

[Redmoggy]

Once you start cleaning off all that Bitumen you are going to find more than just a rotten crossmember. Start saving to do the job right and book yourself a welding course.

Regards
Rod

[kennatt]

As above,if you look inside the car above where that area is you may find that the end of the torsion bar is already starting to poke up through the floor.If I were you I would stop using the car before it causes more damage. It can in extreme cases cause the suspension to fail.

[simmitc]

I can only reiterate as above, the area concerned is an essential structural part of the car. You should be able to see clearly a large nut on the end of the torsion bar, and a smaller nut or bolt head (depending on which way round it's been fitted). I suspect that once you start, you will need the cross member end, at least part of the sills, and a bit of plate for the floor. Depending on where you live, you might find a Minor specialist who could do it for around £200. The problem is: how far does the rot go, it could easily go up to £400; but it is essential to get it done, and to do it properly.

[bmcecosse]

As above - look under the seat and expect to see the T bar reaction arm coming up through the floor... It's a major repair I'm afraid - and apart from obviously failing the MOT - it is structurally dangerous - the suspension could collapse on to the front bump stop first time you go over a bump. I bought a new 'end' - and frankly it wasn't worth the money - I had to reinforce all the welding before fitting it - I could have made a better one in the same time - and it wasn't inexpensive..... The real job is to fit a complete new crossmember - but it is a serious piece of work, and really not for a beginner welder..... What you can do is to ignore the jacking points - which should never be used anyway.

[mattinhertford]

Blimey, it never rains, it....

Thanks for all the replies folks, all good to know. Cleaning off the underside has just jumped to the top of the 'to-do list!!

Now where did I put those car ramps! (Don't worry, I'll be careful under there.)

A related question I've been meaning to ask....I see some people tilt their cars sideways at an angle to do stuff underneath, not talking about the engine-out-completely-flip-on-its-side-job....just sit it on two car ramps on the one side.....is it ok to leave it like that for a week or three, or does that cause unnecessary strain on certain body/chassis/axle parts? I only get 'play time' for a few hours each weekend and would rather leave on the ramps than up and down every weekend....unless that causes any problems?

Thanks

Matt

[bmcecosse]

That won't cause any problems - but you need to dismantle the front suspension to get the torsion bar out - to work on renewing the cross member. Both sides if doing the full crossmember.

[The vast minority]

I don't have the experience of putting a minor on its side so won't comment further on this part of the operation. It would be impossible to do a good job even for an experienced welder with a car on ramps though, best to get it into a proper welder with a 2 post lift as it needs the suspension out.

it's obvious that you need to take the car off the road now and store or fix it for safety sake and you can refurb the suspension components when out to make you feel involved. Don't mix the t bars up though.

Good luck
Al

[Mark Wilson]

I did my complete cross member from above after removing a wide strip of floor both sides,. I'd already done the sill structures and I knew I would be doing all the floor pans, which I'm halfway through.. It only went on the ramps at the rear, mainly to remove the prop shaft. I will be rolling it soon, though, to finish the welding to the chassis leg flanges and the transmission tunnel (and a load of seams to the sills and floor pans. And the spring hangers.....)

Mine had passed its MOT a couple of months before I bought it, with the reaction arms pushing through the floor, but that's another story....

Good luck however you decide to tackle it!

Mark

[Redmoggy]

Just to give you an idea here is a couple shots of my old Minor in the same area.





Keep in mind I had the chassis rail removed at this point.

Regards
Rod

[bmcecosse]

Looks like you have the same 'part Xmember' as I received.. The top and bottom flanges on mine were barely attached to the main part - I deemed it wise to considerably improve the welding with regular short runs along the length top and bottom - both sides.

[mattinhertford]

Hi all, thanks for your input. Next job is to have a proper clean underneath and see whats what. Before I owned Monty he's had some pretty messy floor welding done on the drivers side floor (front and rear) but it looks and feels quite solid. I always known that sometime in the future it would need to be redone properly. I'd cleaned the inside down to bare/clean metal, killed any surface rust and hammerite'd.

I guess the question, once I've cleaned and inspected underneath, will be whether I join the two jobs together i.e. crossmember and whole floor, or just do a temporary (maybe last 2-3 years) job with the crossmember first (obviously only if the floor is strong/solid enough to weld anything too!), and then re-do the floor later. I know there will be cost economies in doing them together, but its a 'flow of funds' issue i.e. I can afford it over time, but probably not all in one go (especially as my wife is not yet over the engine rebuild cost which has just been finished )

I'll clean up and take some photos and then repost for some comments/opinions if that's OK.

Cheers all.

Matt

[bmcecosse]

What's the other side like ? It may influence the decision.....

[mike.perry]

It will be worse than it looks when you start digging out the rot

[mattinhertford]

What's the other side like ? It may influence the decision.....

I'll clean up the lot, take some pics, then post here....

hopefully its....
not..............

Matt

[Redmoggy]

BMC, I'm not saying you were wrong to do so. However I fitted that crossmember as it came, that was about 10 years ago and the car has never had any problems. Last I heard it's now living in the village where they filmed Last of the summer wine.

Regards
Rod

[bmcecosse]

Mine was distinctly flimsy - the top and bottom strips were barely attached - even some gaps showing. As I said earlier - I could just have made one myself quite easily -and would do so next time. I do have a complete new Xmember in stock - which I considered cutting.....but decided not to. I needed the car up and running - so didn't have the time to fit the complete new Xmember. It will have to be done one of these days !!

[mattinhertford]

Hi all,

This is only an 'interim report' from a bit of underbody cleaning I did this weekend. I need to clean up a bit more of a wider area and will then post my 'full report'

If you recall, the question is about a rotten outside end part of Monty's underfloor crossmember, on the drivers side. The question is around whether a temporary fix can be made or if its all out renovation in this area. MOT is May 15 I think and I know it will fail in its current condition, but is it safe enough to drive around until then (I do very few miles, just around town)???

Key findings 1: a previous owner has had a metal plate welded to the rear side of the crossmember, opposite to the fixing arm of the torsion bar!....which looks to have all but welded the two fixing bolts into place

[frame][/frame]

Whilst this will definately need fixing in the future (when funds permit) it does seem to be particularly strong in this area, here is the other side...[frame][/frame]

And here is further along the crossmember....looks pretty good (???) ....the other end has had a replacement welded in in the past, I've not inspected that bit yet.[frame][/frame]

Stepping back a bit, to see the wider area, its quite a patchwork of welding, its not perfect and there are still spots of rust, but to me (a Moggy junior ) it seems fairly solid (for the time being).[frame][/frame]

Both rear spring hangers (is that the right term?) have been re-welded on new patches. Got dark too quickly for me to investigate something last night, but can anyone tell me, thinking of where the rear spring hangers are attached in the above photos, is that a single sheet of metal in that area that I would see if I looked under the rear seat (is that the opposite side?) or is there some sort of air gap, and then another sheet of metal which you see from the other side? Does that make sense? I don't recall seeing the above welding 'seams' from the inside.

Sorry, lots of info for one post ....I will do more cleaning over the christmas break, and post more photos, but happy to hear any thoughts so far. I want to hear that, whilst the fact it'll be a right bugger to remove that torsion bar (when the time comes, because of the nuts literally being welded in place!)...that it's strong enough as it is for the minimal driving I do, and that come MOT time I can have the rotten bit cut out and a new bit welded and that when I'm more flush in a couple of years then I can have the whole lot done properly!!!!......but then not everyone gets what they want for Xmas do they

thanks

Matt

[simmitc]

One thing to consider is that to be insured, the vehicle has to be maintained in a roadworthy condition. We all agree that it will not pass and MOT in its current condition. So, what would happen if you were stopped or involved in any sort of incident?

That said, and with the caveat that a photo cannot tell the whole (hole? ) story, it does not look as bad as it could have done. That plate will help, and the floor looks OK. Clearly the end is not providing much of a connection to the sill. I would define it as safe to move around a yard or workshop without any bracing, and a good basis for repair. I would be wary of driving it.

The rest of the car looks to be a typical patchwork, but plenty of cars have been in daily use looking a lot worse. Well worth getting the cross member (or atleast the ends) done properly.