Mounting a towbar

[Philby]

Hi All,
I'm about to mount a period towbar to my FC sedan and I have a question regarding mounting points.

Although I have a chassis hole that lines up with one of the bar tabs, there is no welded nut or thred to bolt onto. Should I leave it and just use the mounting bolts with the rear bumper, or do something with the tabs?

I'll be towing a 750kg vintage caravan.

Cheers,

Phil

[mcl1959]

I presume your talking about the two tabs (left and right) about half way between the centre of the bar and the bumper mounts?
The bolts go right through the chassis with a crush tube in the chassis section.
Ken

[Philby]

Thanks Ken,

Yes your correct, those are the tabs.

Please excuse my lack of knowledge, but could someone explain more about the crush tubes?

Cheers,

Phil

[Roybeth]

Crush tubes could be better named "anti-crush" tube, but seems most call them crush tubes. My limited knowledge is that they are a heavy duty tube that goes in between two surfaces so that when bolts are tightened up it does not crush the two surfaces together.
Is that what you were asking?

[zulu]

Phil

On my green FE Sedan that I tow my old ply caravan with (says it's only 230 kg on the rego )
the tow bar is just bolted up to the rear bumper bar bracket bolt locations with longer bolts

At some stage 1 of the internal nuts welded on the inside of the chassis rail has let go and someone has drilled a series of holes to gain access and removed a small piece of the inside edge of the rail in order to fit a new nut

I have never bothered to fit crush tubes to this car, however on the Ambulance Panel van crush tubes have been fitted to it's tow bar, sorry can't get pics of it atm

As your van is heavier, it would probably be a good idea to go with the crush tubes, maybe someone can advise the best way to do this

Gary

[Philby]

Thanks Roybeth and Gary,

Very useful information.

I'll start my research, in the meantime I'll happily accept advice regarding who could do this type of job. I.e is it something a competent home mechanic could do or should it go to an engineer?

Cheers,

Phil

[mcl1959]

Handy person will have no problems. Find some steel tube with ID just over bolt size and a wall of approx 1mm or greater    So let's say tube ID is 8mm and OD is 11 mm.
Hole in the bottom of the chassis is 8 mm and 11mm at the top.
Slide the tube into the hole and Mark the length of the tube and cut. Ensure tube does not protrude from the chassis rail.
Bolt the tow bar in place and then install the tube onto the bolt with a large washer and slide into place from above. Install lock washer and nut and tighten.
Tube can be welded in place but is not really necessary

Ken

[Dr_Terry]

Crush tubes could be better named "anti-crush" tube, but seems most call them crush tubes. My limited knowledge is that they are a heavy duty tube that goes in between two surfaces so that when bolts are tightened up it does not crush the two surfaces together.
Is that what you were asking?

Yes, the English language, or rather the Aussie version is a little odd in that regard.

We use the words 'sway bar' when referring to an anti-sway bar & we use the term 'pollution gear', when it's actually anti-pollution gear!!

Dr Terry

[Philby]

Thanks Ken.

Thats clear and sounds quite achievable.

Terry - yeah, we are good with Australianisms.

Cheers,

Phil