Technical Suspension top mounts

[mj2k]

Just had a quick thought on the 500 front suspension top mounts. Seems it's inevitable the thread on the strut will go rusty and the bolts will stick because the top mount's cup (which really does nothing except stopping the suspension moving too far downwards; kindof an inverted bump stop) acts as a little bowl, to store lovely rusty water in.

Just thinking, since the cup carries very little load, would it be OK to drill a small drainage hole in it? That combined with a good coating of Hammerite and some copperease or suchlike on the threads may be enough to stop changing the strut mount bearing being a particularly horrible job.

 

[Ralf S.]

The top mount cup should have a little plastic plug or rubber shower cap on it.

The Fiat ones may not completely keep the water out but tend to go AWOL, so you may just not have any fitted. Otherwise there's aftermarket ones, like the attached link:

https://www.ebay.co.uk/itm/265356853555?hash=item3dc8804133:g:qqQAAOSw~YJhZIRG

The pictures also show the Fiat cap, if you don't have those.


Ralf S.

 

[mj2k]

The top mount cup should have a little plastic plug or rubber shower cap on it.

The Fiat ones may not completely keep the water out but tend to go AWOL, so you may just not have any fitted. Otherwise there's aftermarket ones, like the attached link:

https://www.ebay.co.uk/itm/265356853555?hash=item3dc8804133:g:qqQAAOSw~YJhZIRG

The pictures also show the Fiat cap, if you don't have those.


Ralf S.

Thanks,I've got those alright

Main issue seems to be it acts as a little semi-sealed box with the cap on where water can condense, and it's got nowhere to escape to so acts as a rust-friendly microclimate. Similar issue to the subframe mount box section on the rear of the Austin 1100/1300, where it had a foam rubber filler to stop noise. Only the foam did a much better job as a sponge than it did as a noise canceller, so most of those little BMC cars paid a visit to the scrapyard with rusted out subframe mounts before their 15th birthday.

I guess the other alternative would be to put bathroom sealant round the cap to prevent air ingress, or put a rubber cap filled with grease over the strut top threads.

 

[Ralf S.]

I stuffed some plastic tube over the damper rod threads that project out of the top mounts of my Stilo. It suffers similar issues but not as much as the 500 since the cup is slightly less dished.

I can't remember where the plastic tube came from.. they might have been part of the packaging for the new dampers.. but the idea would work.. just get hold of some tube of the right diameter from fleabay and them grease up your threads and "screw on" the tube, then cut off any excess.

I wouldn't silicone the caps on.. since even a bit of water creeping in there would then be trapped and would probably be worse, since you wouldn't ever remove the cap. You can try something like a piece of clingfilm and an elastic band underneath the cap, to give it a bit more waterproofing... but it's best to leave them open to simple inspection every so often.

You reminded me that I need to have a peek under the caps on Rasputin, the Younger Mrs S's 500...

Ralf S.

 

[mj2k]

I stuffed some plastic tube over the damper rod threads that project out of the top mounts of my Stilo. It suffers similar issues but not as much as the 500 since the cup is slightly less dished.

I can't remember where the plastic tube came from.. they might have been part of the packaging for the new dampers.. but the idea would work.. just get hold of some tube of the right diameter from fleabay and them grease up your threads and "screw on" the tube, then cut off any excess.

I wouldn't silicone the caps on.. since even a bit of water creeping in there would then be trapped and would probably be worse, since you wouldn't ever remove the cap. You can try something like a piece of clingfilm and an elastic band underneath the cap, to give it a bit more waterproofing... but it's best to leave them open to simple inspection every so often.

You reminded me that I need to have a peek under the caps on Rasputin, the Younger Mrs S's 500...

Ralf S.

Sounds like a plan

I've got plenty of spare hose laying around so pretty sure I can find a bit of the right diameter, and a giant tub of copperease to smother the threads with.

I noticed the FSM 'fix' is to wire brush the threads and smother them in penetrating fluid so I guess Fiat has come up with a solution of sorts, which is more than can be said with BMC / Leyland - their 'fix' was to replace the pretty Pininfarina-designed 1100/1300 with the monstrous lunatic-with-a-crayon-designed Allegro :yuck:

 

[chris3234]

Give them a good coat of paint and fill the cup with grease then stick the cap over would get my vote

 

[Ralf S.]

Trouble is, when water gets into the grease, it'll eventually turn into a paste of nasty and start to smell of fish... Ahhhh Ahhhh


Speaking of livestock... I'm currently (Alfabook group) getting a load of Facebook adverts for some stuff called Lanoguard. It looks like a cavity wax that you just spray onto metal surfaces, and which then dries/hardens into a wax-like substance. That (being dry and waterproof) or something similar to it, might work... Just it smells of sheep rather than fish... but I'm in Wales these days, so the sheep gets my vote..


Ralf S.

 

[John202020]

I've silicone'd our caps on, it seems fine I've had the cap off a few times over 6 years and no water or rusting just run a fine blade under rim to remove taking care not to cut the rubber.
Did consider a small hole but that will let water in,I replaced the cups for new when I did the front suspension

 

[mj2k]

Yuk, there seems to be a lot of talk about fishy smelling 500s on here over the last couple of days so I don't think I'd like to become part of that trend

Think I'll stick with the cover for the threads and make sure the scuttle drains are nice and clear to be on the safe side.

 

[MOOKEV]

Can you change the cups easily, wondered if you can simply unbolt and replace with new one?

 

[mj2k]

Can you change the cups easily, wondered if you can simply unbolt and replace with new one?

Yes it's do-able without having to jack the car up, though you do have to remove the scuttle cover. Biggest issue is corrosion on the threads on the ends of the struts though, you might be able to get away with a lot of wd40 after wire brushing the threads, but chances are after X years sitting in a little water bath in the cup the nuts holding the cups on will be seized solid.

And without an impact gun to loosen them (which the FSM says might damage the struts), most likely the hex socket in the top of the struts will either round off or snap when you try to undo the nuts, and then you're in a whole world of pain.

So realistically unless you religiously remove the cups every few months, clean / lubricate the threads and replace the nuts it's best to leave replacing the cups until you have some other major work to do like replacing the struts or strut tops.

 

[MOOKEV]

Yes it's do-able without having to jack the car up, though you do have to remove the scuttle cover. Biggest issue is corrosion on the threads on the ends of the struts though, you might be able to get away with a lot of wd40 after wire brushing the threads, but chances are after X years sitting in a little water bath in the cup the nuts holding the cups on will be seized solid.

And without an impact gun to loosen them (which the FSM says might damage the struts), most likely the hex socket in the top of the struts will either round off or snap when you try to undo the nuts, and then you're in a whole world of pain.

So realistically unless you religiously remove the cups every few months, clean / lubricate the threads and replace the nuts it's best to leave replacing the cups until you have some other major work to do like replacing the struts or strut tops.

Thank you. My plan is to clean and derust as best I can, then keep it clean and maybe greased. Then as you say, wait until work becomes neccessary.