Centre crossmember

[bmcecosse]

Has anyone done a 'how to do it' on the subject of renewing the center crossmember? I fear this job is looming large in the near future!

[Jefftav]

I am sure you know that you can use repair sections depending on how bad your cross member is. I can put you in touch with the bloke who did mine but he doesn't do computers so you would have to phone him.

from what I remember I had to strip out the interior and take off the propshaft, brake and fuel lines and wiring loom. He drilled out the spot welds and cut the floor either side of the xmember then off the sills ( i assume as I wasn't there to see that bit) to release it. Replacement would have been straight forward with the floor being repaired once the new xmember was fitted but unfortunately he found some bad repeairs/rot on the floors and ended up replacing the floor panels. When I seen the rotten xmember I was glad to have had it replaced as it couldn't have been doing very much.

[bmcecosse]

Thanks Jeff. Did he tip the shell on it's side ? I've looked at it today and it doesn't seem TOO bad, provided the MOT lad doesn't poke/hit it too hard! MOT first thing in the morning - fingers crossed!

[Jefftav]

No Roy, He did it with the car on stands. I asked him about using a roller but he prefers doing it with the car flat and weight supported on stands. Just his way I guess! Hope the MOT tester is sparing in there hammer wielding, my xmember was quite bad and it still passed an MOT.

[bmcecosse]

As did mine! Another year's motoring, and only an 'advisory' on a cracked weld on the 3 branch manifold. Since removed, rewelded, and refitted! But - interesting he did it 'from below' - and seeing now the need to drill out all these spot welds, I can see that may be the best way to go. I should of course put the car off the road now and get on with it - but of course, having blagged a new ticket - I won't!

[PSL184]

'till next year

[bmcecosse]

A lot can happen in a year..............

[Jefftav]

It's such a big job to do try to set aside some time to do it and you may find the xmember & other parts for floor repairs or repairs to sills on ebay/autojumbles from folk who have bought the parts and then abandoned the project.

[billlobban]

Nice to see you're back on the road for another year 'o wise one' there's nothing like a good bit of welding splatter to keep the spirits up

[chickenjohn]

Has anyone done a 'how to do it' on the subject of renewing the center crossmember? I fear this job is looming large in the near future!

I've never done this job myself- luckily, my Traveller has a sound crossmember and the convertible project only needed one end replacing.

However, there is a good "how to" guide on centre crossmember replacement in the Morris Minor club manual- the CD version is not too expensive. Or as a club member- you could phone up and ask Rob Thommasson who wrote the article.

[bmcecosse]

Thanks for tips/hints etc - I bought the new crossmember two years ago - when I first feared it would fail. It's still wrapped up under the bed....... Floors etc are ok - I think! It is going to need the full job doing - ends would not be a success. My Qs are - is it possible to just cut/chisel/grind it all away from below - or is it 'essential' to drill out the (many!) spot welds from above?? Must be someone who has done the job??

[taupe]

BMC

In addition to the spot welds there are lengths of seam weld to the floor especially on the centre section.

I havent done mine yet but if I was doing one on a car with reasonably good sills and floor I would leave the car the right way up. Most of the welding can be done from above.

First I would cut the floors either side of the outriggers in a strip about 3" wide and cut through the X member just before the front chassis leg joins. You can then tidy up the sill/jacking point areas.

I would then drill out the spotwelds over the curve of the transmission tunnel - raise the car up and attack the seam welds (theyre about 1" long and 5 off I think) then thoroughly clean up the centre under the tunnel and grind off whats left of the X member from behind the ends of the chassis legs.

Once all cleaned off place the crossmember from underside and jack up into position as you havent touched the chassis leg positions alignment is straightforward. Put a bolt thro the handbrake mounting and weld the nut on if its not already on the repair section.

Plug weld thro the holes in the transmission tunnel (where you drilled out the spotwelds previously)

Drill right thro the web of the new X member then plugweld into the front chassis legs from the rear to replicate the spotwelds. (you can pre drill the holes). You can get a grinder in at the back if you need to smooth them down afterwards - its much harder to clean up if you weld the chassis legs at the front.

Plug or spot weld the replacement strips for the floors (these can be welded on before you fit the X member if you want) then seam weld the floor.

Finally I would reinstate the short seam welds underneath. Also fit jacking points if you want them.

Theres lots of ways of doing the job- hope this helps.

Regards

Taupe

[DAVIDMCCULLOUGH]

It would be difficult to do just from below. I have replaced a couple of complete crossmembers, undo the torsion bars bolts making sure to mark which bolt hole onthe adjustment plate was used. Drill out as many spot welds from above as possible. There were some big gas weld that must have been done in the factory near the centre. Grind or chisel thses away. The ends of the chasis legs are obviously attached as well. If your in luck the sills were it attaches will be sound but chances are when you start removing bits they will be a bit crusty.

Clean everything up well and offer up the new crossmember, I found the easiest way was to bolt it to the back of the torsion bars to make sure it was in the correct place again and tack all back into place once again. Then when your happy that all is where it should be you can remove the torsion bars to get welding properly at the front of them. I have only ever welded with oxy acetelaine and is is great for this job, it quite heavy steel to mig. You can weld through all the spot welds from above to the main crossmember below.

Not a quick job, but fairly straightforward.

[bmcecosse]

Thanks both - taupe and David. You give me hope! My worry is - that to tilt the car, I need to use a roller and it bolts to the suspension, which may not work too well if T bars removed as they will need to be to do the job. So if it can be done from below - that does sound rather more practical for me. Not too sure about cutting away the floor in a 3" strip! My floor (and sills) looks good - it's just the X member that has delaminated because it's not been properly protected earlier in it's life. I dozed it with rust killer when I got the car 8 years ago now - and then plastered it with useal which has kept it going up to now. But one day - it IS going to fail the MOT....... I have Mig + stick + spot weld and oxy acet welding capability - so can pretty much cope with it all! Question from me now - are the spot welds to be drilled out just across the curved section of the transmission tunnel ?

[Jefftav]

FRom what I remember BMC the spot welds were only on the tranmission tunnel and this part remained untouched apart from removing the spotwelds of course. The floor and sills on my Morris also looked OK until we started removing the xmember and then we seen them crumble to dust all the fun of the fair so they tell me but it turned a big job into a bigger one.

[bmcecosse]

Thanks for the honest replies! I think it will be getting another thick coat of underseal meantime...........

[Jefftav]

Sounds like a wise move.

[bmcecosse]

Trouble is - the useal is about 1" thick now !!!!!!!!

[Jefftav]

No wonder it passes the MOT the tester can't even see it.

[billlobban]