Strut top mounts

[Graydan]

Hi, has anyone changed their top mounts?

Mine need doing and I've attempted it but the top nut is very seized and my impact gun will not touch it. Also the pinch bolt for the hub carrier is also sized solid.

Has anyone got any advice for this please? I have tried heat on both bolts and no luck.

Thanks

[insanitybeard]

Rusted front strut top nuts/ threads are famous on the Mk1/2 Galaxy because of their position, the cups fill up with water draining from the scuttle and as there's no drain hole in the cup the water stays there and they corrode solid. The situation is made worse by the less than ideal access. If you take a read here, this is one solution to the problem. I've also wondered if jenoliting the theads a few days before attempting to remove the nuts would do any good but if all else fails, the linked method will provide a solution!

The wheel knuckle to strut pinch bolt is more tricky. Shearing it off will render the knuckle useless unless you can remove the knuckle/ strut complete and get an engineering shop to drill it out for you. You could try some penetrating oil and then gentle warming of the knuckle followed by freeze spray once it has cooled in the slit where the pinch bolt clamps to see if the combination of heat and cold will free it off, you may need to repeat the procedure a few times though.

[bigdave982]

Does anyone know the thread size of the strut tops?? Might be worth getting one of those "die nut "thread cleaner things, look lie a die but hex shape , to clean threads up before trying to undo nut. Ita only the corrosion that stops em undoing after all

[insanitybeard]

I was wondering just the same thing the other day! There may be variation depending on model and build date but if this (Mk2) is to be believed it's M14x1.5, comes up the same for a Mk1 as well.

Something like this, just need a UK seller!

[johnnyroper]

If they are that badly rusted I can't imagine the correct size thread cleaner having much luck. It may clean up a bit but chances are thread won't be useable as it will have reduced in size due to the rusty material.
If they are that far gone it will not come un done only way I can see is cutting off and replacing it all.

[johnnyroper]

The other thing to add is those dies are good for cleaning up threads that are slightly damaged prior to putting a nut on. They would not be able to clean all the thread up as it would but up against the original nut and not go all the way down so the threads closest to nut would still be rusty and damaged.

[insanitybeard]

True but I think if you were prepared to take the time and effort it could be done- as this poster did. As I said previously I think some chemical rust treatment could also be applied in advance to shift some of the corrosion. Whether reusing such corroded/ knackered threads is acceptable practice is another matter, though the actual part of the thread doing the work is the part hidden within the nut, likely to be in much better condition than the rest of the thread! If you wanted to try to save your original struts it could be worth a go, if you're ditching it all then there's no point in bothering.

[johnnyroper]

Yeah you are right the thread under nut should be in workable condition.
Also I suppose it's not super critical as it only holds top cap on and does not retain the spring tension does it?

Not the best of designs really with restricted access if only they had put a plastic cap on it like other manufacturers.

[insanitybeard]

Yeah, there's another nut underneath the top mount that holds the spring tension. Not the best of designs like you say, either a drain hole in the cup or a rubber cover over it would have made all the difference.

[bigjeeze]

If they are that badly rusted I can't imagine the correct size thread cleaner having much luck. It may clean up a bit but chances are thread won't be useable as it will have reduced in size due to the rusty material.
If they are that far gone it will not come un done only way I can see is cutting off and replacing it all.

Go to the description of the re threader - look for the US flag in the bottom left then change it to the UK and away you go.

[Rntaylor]

I've changed 2 sets of late, one on my old Mk1 Sharan and another on my Mk2.  I also managed to shear off the pinch-bolt that holds the strut to the carrier!  After that I resorted to having to remove the strut with the hub carrier attached.

You need to remove the driveshaft from the hub, this needs to be undone with a 27mm socket while you get someone to apply the brakes.  Remove the wheel, brake calliper, the steering track-rod end, and then the lower ball-joint.  It's probably easier to remove the ball-joint from the carrier by undoing the two 8mm Allen bolts.  If you can't undo these you'll need to undo the nut that holds the ball-joint to the lower arm, then release the taper. Once you've managed to undo the top nut the entire strut with hub carrier and brake disc will come out.

On my first one the top nut just wouldn't undo, so the only option was to cut the steel cup washer to release the assembly.  Once out of the car the damaged nut was successfully removed.

The broken bolt in the hub carrier had to be drilled out and replaced by a suitable nut and bolt.

If I do the job again I'd certainly not attempt to remove the pinch bolt, but take the whole assembly out as described above.

Having said all that, I managed to change the top mounts and springs on my Mk2 (sports suspension) without having to take the strut out of the vehicle.  Once the top mount was undone, the strut lowered enough to use some Spring compressors to release the tension and then second nut and Spring. The new spring was 'wound' onto the strut and then reassembled. Much quicker!