Sheared front damper bolt

Post by **millerman** » Sat Jun 30, 2007 8:50 pm

When removing the off-side front damper on my project traveller I found that one of the mounting bolts had sheared off flush with the bulk head. It looked as though it had broken some time ago (I can't blame 20/50 oil!!)

I tried to drill out the stub and failed and now the hole is to big for a 5/16 (8mm) tap.

So, what's the best plan? Drill a 1/2" hole and weld in a 8mm nut flush with the bulk head or, has anyone solved the problem another way?

Post by **rayofleamington** » Sat Jun 30, 2007 8:57 pm

I found that one of the mounting bolts had sheared off flush with the bulk head.

They do break occasionally - which is why the thick fluid wasn't recommended by the guys who designed the suspension.

The nuts are (were) held captive on a plate that fits in the bulkhead crossmember. It's possible to remove the whole thing by making an access hole through the inner wing.

Otherwise - yes the alternative is to weld a nut flush in place, howevever it needs to be a very solid job!

Post by **kennatt** » Sat Jun 30, 2007 9:14 pm

not sure if yours is the same as my split screen but just had a look at mine,when you say sheered off at the bulkhead do you mean at the box section that runs across the bulkhead(Like mine). If so then I would probably cut a flap in the top of the cross member and weld a nut on the inside so that i could put a new bolt through. Then re weld box section. Or drill straight through with a small pilot drill to see where it came out on the inside of the car,then if not in the way of anything else,drill through and put long bolt and nut right through. The box section on mine looks heavy enough so that when tightened it wouldn't crush the box section.Looks like it would come out somewhere just above where the upwards sweep of the floor meets the inner firewall. good luck with it

Post by **bigginger** » Sat Jun 30, 2007 9:28 pm

kennatt wrote: drill straight through with a small pilot drill to see where it came out on the inside of the car,

If the same as a series 5, it doesn't, it comes out inside the box section - or am I not understanding?

Post by **Welung666** » Sun Jul 01, 2007 11:12 am

I think he meant straight through the box section into the cabin and use a really long bolt ;)

Post by **bmcecosse** » Sun Jul 01, 2007 11:12 am

Drill it 5/16" and then tap a thread 3/8" (or 10mm if you don't mind metric on your Minor) and then run a clearance drill through the bolt hole in the damper - there's plenty of meat on it.. It is important to check all these bolts from time to time - even with thin oil ! If that doesn't work - then it's semi-major surgery I'm afraid!

Post by **jonathon** » Sun Jul 01, 2007 11:50 am

Drill out to a 10mm or 10.5mm hole and fit a 'steel' not alluminium rivnut

Post by **Redmoggy** » Sun Jul 01, 2007 1:14 pm

Why not helicoil the old captive nut? Shlould be plenty of meat left.

Post by **bigginger** » Sun Jul 01, 2007 2:05 pm

Welung666 wrote:I think he meant straight through the box section into the cabin and use a really long bolt ;)

Hence my confusion - it doesn't emerge inside the cabin, there's a 'big' space in between the box section and the toe board

Post by **bmcecosse** » Sun Jul 01, 2007 2:44 pm

Helicoil is all very well if you have the kit! V expensive - and probably NOT enough thread for it to grip - they are really only any use in deep blind holes in solid parts.

Post by **kennatt** » Sun Jul 01, 2007 4:48 pm

yes straight through into cab area and very long bolt not a good idea now that I think about it, forget I mentioned it,stupid idea really

much better suggestions elswhere

Post by **bmcecosse** » Sun Jul 01, 2007 6:18 pm

I've asked before and never had a good answer - but what are the other tapped holes in that area used for ? They almost look as if they are to accept an alternative damper - but if so I have never seen one. Anyone know if there is a bigger/heavy duty/'export' damper that would fit on using these alternative holes ?

Post by **bigginger** » Sun Jul 01, 2007 6:28 pm

There was a prototype for export models, but it never got into production, I've read somewhere.

Post by **bmcecosse** » Sun Jul 01, 2007 6:43 pm

Ah-ha! It would solve the problem above if alternative dampers could be found. Seems odd (maybe not for BMC!!!) that they would continue drilling/tapping holes that would never be used for years and years!! This of course is the methodology of all the fancy Japanese Manufacturing Ideas - seek out and eliminate WASTE!!!

Post by **jonathon** » Sun Jul 01, 2007 6:45 pm

One of my neighbours customers used to and still does export the uprated leverarm dampers. Unfortunately he has moved and I'm still trying to track him down a year later. They mainly went to OZ NZ and S Africa.

Post by **bmcecosse** » Sun Jul 01, 2007 7:35 pm

And these bolt into the alternative holes J ?

Post by **jonathon** » Sun Jul 01, 2007 8:02 pm

No, they are visually the same Armstrong units but uprated, so fit in the same location. Thought the extra holes were either shipping or jigging related.

Post by **millerman** » Sun Jul 01, 2007 8:20 pm

Thanks very much for suggestions.

My neighbour has a Helicoil kit with a 8mm coil so we're going to try that one evening this week.

If that is not successful then I'll try a rivnut which I had thought about after my original post

Post by **bmcecosse** » Sun Jul 01, 2007 10:14 pm

Probably 'uprated' by filling with the thicker oil!! And yes - I know the valves can be adjusted (been there) , and probably the little orifices can be changed too - but oil is the biggest factor.

Post by **millerman** » Thu Jul 12, 2007 8:29 pm

Helicoil fitted, the name of the product used is "recoil". Everything tightened and tabs bent over, unfortunately can't be given a good road test, hopefully in 2/3 months.

What torque should be applied to the damper bolts?