Cracked bulkhead at subframe mounts - what would you do?
Turbo Mini Forums

Evening chaps,

Having just got mini back on the road, I was under it this morning trying to find a small oil leak, when I noticed something looking rather off with my front subframe rear mounts....



Yea I know, my exhaust is utterly fucked. a replacement is due ASAP, but as I'd planned to be turbo'd by now, I hadn't bothered.

Passengers side mount:



Drivers side mount:



So, what's the usual plan of action? I'm thinking that on a ramp, I should be able to remove the subframe mounts, drill the ends of the cracks and seam weld them up. THen I assume I'd weld a big plate onto the inside on the shell then redrill the mounts?

I'm off to the ring in 2 weeks time, So I really need to get this sorted ASAP!

Cheers

Nick

Mr. Prawn, the friendly Crustacean- slowly making steps towards forced induction.

Sounds like a good plan

sounds good if you remove the mount you should be able to get a plate on the inside and out belt and braces?

Common, you can try and weld up the cracks but when I have repaired them before I cut out all the cracked area and seam welded in some 1/8 plate. Then redrill the holes.

Those solid mounts do not help. Fit these instead http://www.minispares.com/Product.aspx?ty=pb&pid=34759

I did exactly what Tom suggested on GinoR32's mini a few months back. The only sure way is to replace the damaged metal with a beafier section.

Own the day

Does the bigger base plate on those make them that much better Sprocket?

Cheers colin, I guess I won't find out until i pull the mounts off and see what lies underneath. Would you put the spreader plates on the underside, or inside the car on the floorpan?

Mr. Prawn, the friendly Crustacean- slowly making steps towards forced induction.

Thanks Colin - makes sense. Must check what are on mine.

As for strengthening - inside the car surely? Otherwise you are altering (admittedly only slightly) the mounting dimensions of the subframe.

Outside. I have welded plates on roughly the size of an A4 piece of paper. they almost meet the steering rack mounting, and go right down to where the toe board meats the floor. I'll try and find a picture later. its only 0.9mm steel, so hardly noticable.

I've just found a similar crack on the 998Ti - MOT is on Friday.

I'm just going to weld the two sides of the crack back together. It's not like corossion where you need to get back to good metal.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

This is what I have done on all my race shells. Maybe etreme, but this panel is a bit floppy. the Mk1 attachement on the floor and bulkhead join is a much better idea.

Edited by wil_h on 31st Aug, 2010.

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

www.twin-turbo.co.uk

On my first mini it cracked here, we put some monsterous plates in and I swear it helped keep the car in a better state when I crashed it.

Infact I was so convinced we put a slightly thinner version into my car when we rebuilt it

^ I like that idea!

If something is worth doing, it's worth doing half of.

I had planned to do somethim similar, but not quite so large to mine. I was planning to plate up both sides though.

Wil - would that hand break lever pass an MOT??

Would it need to?

If something is worth doing, it's worth doing half of.

Was a bit too light that one and it bent. It has a standard one on now.

Of course it'd pass an MOT, the tets is on the braking force, not the handle.

But as above, it broke, which probably would be a fail.

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

www.twin-turbo.co.uk

Where did it break? Just looking at where I can/can't at lightness to my car...

Mines a bit worse than I thought:



Still going to clean it up and weld it back together.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

I have to say I really don't like the later design - it's only moved up to the weak/flexible toeboard to fit the rubber mount in.

The MK1/2 design, which is what I've used (2 bolts per tower and all solid by design) is so much better meeting the floorpan and toe board where they join (so is thicker and is at a change of section where the strength comes from the two different angles).

If I cold get hold of a Mk1/2 subframe at a sensible price, I'd do it again on my second shell.

Schrödinger's cat - so which one am I ???

Welded and painted:



The crack actually extended up the side of the strengthening plate behind the subframe, so I had to weld it on the inside as well.

I only did the welding. My apprentice did most the hard work.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

Well, it was good enough for the MOT guy - got a new green one

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

I had a quick look at my SPI shell last night and it seems to have got some little spreader plates from the factory on in inside of the car. Is this the case with earlier one's too?

If something is worth doing, it's worth doing half of.