ok guys i pulled my front subframe out about a month or 2 ago because the tower was cracked, and put in another good 2nd hand one.
i lifted up bonnet the other day to c that this one is cracked in the same spot. now i have springs in it instead of rubber donuts could they be doing this ???????? .

Did the new one go in easy enough?

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yer no worries at all y

No twist in your body.

Did you have the springs in the old frame?

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yer and it cracked in the same spot

Go back to the rubber donuts. The springs are bottoming out. They do not have or allow the same travel as the donuts do.

Or you can set your Hilo's lower - much lower. Don't try to set them near stock height.

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I find it very hard to believe that springs are the couse of that.
Including myself, lots of people are running spring set up for a lond time no issues regarding hight or bottiming it out.
If anything; I find my spring setup much more comfortable.

Anyways back to original issue; Is your front hight very low?
If yes that might create some space when the front airborn, and when lands on the road creats big impact. (when I say airborn I do not mean like the movies just when the pressure is of the suspension.
Just an idea.

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Since light travels faster than sound, people appear bright until you hear them speak

If the suspension is very low, then the impact will be absorbed by the rubber bump stops.

If each subframe has lasted 40 years in original configuration, only then to be cracked in a very short time, then yes it would be worth looking very closely at the new springs.

That's not to say you can't perform a little welding to reinforce as well as repair the towers. Its cheaper than swapping everything out.

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SooperDooperMiniCooperExpertEngineering

All garage work involves equal measures of enthusiasm, ingenuity and a fair degree of irresponsibility.

Is this where it cracked?

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i stitch weld them around the top caps (where they`re cracking) & then strap them-->
IE: weld straps of metal along the top & bend them down the sides of the towers & then weld them down the sides as well (ala rally mini subframes)

Job done, no more worries

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No offence intended here but--> anyone writing a book about minis 30 years ago may not have experienced such worn or stuffed-with components as we are finding these days.

You should put your heart & soul into everything you do.

Welding around the top edge should cure the cracking but I would chuck the springs and refit the donuts, I agree with the others when they say it sound as if the springs are bottoming out.
Matt the Mini man has suggested this, adding the extra steel I would only do if you plan to jump the thing over railway lines

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Have a Nice Day.
If already having a nice day please disregard.

were it cracks is were the bolts come screw into the edge of that like were it rises up to the bolts it cracks

Come again?

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http://www.youtube.com/user/Hanras

He means it cracks where the bolts come out of the tower. There is a risen up diamond shaped piece. Its cracked here.

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You have got the spacers fitted? I've seen them missing on cars before.
I race my mini and haven't managed to crack the subframe yet!

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Too many cars, and too little time.