Technical Subframe options

[threes]

Hi. I’m the market for a 4x4 and doing some reading I’m getting a little concerned about subframe rust and what seems limited options once rust has set in.

If I find a panda with a decent looking subframe, no MOT history of rust - is it realistic to get (both?) subframes galvanised/ treated for longevity.
Or not worth it ?

Just weighing up options.
Thanks !

 

[koalar]

If I find a panda with a decent looking subframe, no MOT history of rust - is it realistic to get (both?) subframes galvanised/ treated for longevity.
Or not worth it ?

Yes and yes

Keeping them free from mud and greased, oiled or wax oiled should be enough

But finding a 169 worth spending the cost of galvanising on is going to be the hard part, 169 pandas are getting towards end of life

I'd start with the latter cars, something around 10 years old

The viscous coupling in the pre 2007 don't age well, finding someone in the UK to service them isn't easy, supply in the UK is none existent,.last time I looked it was about a grand to import one from Italy

 

[threes]

Yes and yes

Keeping them free from mud and greased, oiled or wax oiled should be enough

But finding a 169 worth spending the cost of galvanising on is going to be the hard part, 169 pandas are getting towards end of life

I'd start with the latter cars, something around 10 years old

The viscous coupling in the pre 2007 don't age well, finding someone in the UK to service them isn't easy, supply in the UK is none existent,.last time I looked it was about a grand to import one from Italy

Thanks for this. I’m currently looking at 2009/2010 1.2 4x4s.

But perhaps I should look at later TA models also?

Just seems the pool of good options is going to be small if I stick with mk3s - and the options for fixing them getting smaller ?

 

[koalar]

Thanks for this. I’m currently looking at 2009/2010 1.2 4x4s.

But perhaps I should look at later TA models also?

Just seems the pool of good options is going to be small if I stick with mk3s - and the options for fixing them getting smaller ?

That's how I see it

@aaron500 has owned one for sometime maybe they could advise you further

Rear sill rot is fair common now, on the c pillar and jacking point

They can be patch for £50 but to pay someone it approximately £200 per side for a proper job

 

[rmjbn1]

If I find a panda with a decent looking subframe, no MOT history of rust - is it realistic to get (both?) subframes galvanised/ treated for longevity.

The main tube on the rear subframe that seems to rust looks open ended
If you find one that isn't too rusty, I'd imagine pouring old engine oil into the tube every year and smearing all over with oil or grease would be effective

 

[GerarGD]

I can tell you what has been done in my Frankenpanda project to address this topic, since that piece was 20 years old, enduring the hard Nordic winters... I actually learned this from the Panda 4x4 FB group.

The issue is, we could say, a design flaw (or cost saving measure) from FIAT: The original rear subframe has open ends, where water and dirt enter and end up rotting the part from the inside.

If your subframe is not fully rotten, you should sandblast it, weld shut those open ends, and powdercoat the part. In my case, it was advised to source one in better condition, to which we applied the said measures.

I hope it will last many many years!

 

[svennelainen]

I don't know why we keep saying cars are getting to an end of life. I still drive a Volvo Amazon from -66.
I rust repair my Panda at the moment. I will take off the sub frame and renovate it, reinforce it, add drain holes, weld the ends shut and send it to a zinc factory. My Panda will probably survive me after this.

 

[koalar]

I don't know why we keep saying cars are getting to an end of life. I still drive a Volvo Amazon from -66.
I rust repair my Panda at the moment. I will take off the sub frame and renovate it, reinforce it, add drain holes, weld the ends shut and send it to a zinc factory. My Panda will probably survive me after this.

Because of corrosion here in the UK on salted roads


The zinc layer is 8 - 16 microns

And from 2007

The zinc layer is 10 - 12 microns

Unpainted areas will loose approximately 1 micron per year

It becomes uneconomical to repair safely

After 15 years they normally look like this or much worse

If it's had a simple sill patch in the past covering up the issue but not addressing the problem the jacking point and C pillar will almost certainly need cutting out

To pay someone to fix properly is at least £250 per side plus VAT so really it's beyond economical repair, unless you can fabricate yourself, if you are paying a mechanic to do your repair it is usually works out cheap to spend a little more in the first place, in my opinion

Yes there are examples that are still rust free or not too bad, but they are getting rarer

They often don't look bad from the outside

But not so good underneath

 

[jrkitching]

I don't know why we keep saying cars are getting to an end of life.

If you are sufficiently determined, you could keep it on the road for a very long time. Anything can be repaired, given time and money; the question is, at what cost?

What we really mean is end of economic life; the point at which spending further time and effort to keep the car on the road is a losing strategy compared to the other available options.

A lot depends on the situation of the owner; someone (like yourself) who is capable of carrying out their own repairs, and is not costing their time, can economically undertake repairs which would make no financial sense if you were paying someone else to do the work. The decision to scrap or repair can be as much about the circumstances of the owner as about the condition of the car.

Everyone has their own definition of when it becomes uneconomical to continue to repair an older car. For me, once the likely cost of keeping it roadworthy exceeds what it would likely cost me to own its replacement, then it's time to say goodbye. The details of how to do such a calculation probably merits a separate thread.

The substantial increase in the cost of new cars has meant that many older cars are now being repaired that previously would have been scrapped.

 

[svennelainen]

Any poop box will rust, if it is made in Italy even faster.
I've already posted images of my sill rot but they are coming along nicely and with a 3 mm L-beam as a base it will stay intact a few decades. But yeah they apparently need repairs after 20 years. A lot of Polish and Italian people use the 169 as a weekend toy so they will be alive for many years to come.

BUT, this thread was about the sub frame...

 

[puntodad19]

If you have in door repair space, enough room and money, as well as time and the will to repair body rot, it can be a very rewarding past time.

Some vehicle body panels are now difficult to get, as well as 18gauge tin plated sheet steel, or thicker as the need arises, but indoor space ( or living in a hot dry country ) is the bug bare.

As to keeping corrosion at bay, old engine oil and a suitable *thinner* , is easy and very economical.

It works, but keep away from rubbery stuff.

 

[puntodad19]

As a matter of interest, no fire extinguishers seen.....but, when using your mig or stick welder, what fragile expensive and easy to kill computer bits and bobs are people removing from the vehicle please ?

 

[jrkitching]

when using your mig or stick welder, what fragile expensive and easy to kill computer bits and bobs are people removing from the vehicle please

It's not just fragile electronics that are at risk here.

Wasn't that long ago that a garage managed to weld the handbrake cables solid when doing a patch repair on a Panda twist beam spring pan.

You need to think about where that return current is going!

 

[koalar]

It's not just fragile electronics that are at risk here.

Wasn't that long ago that a garage managed to weld the handbrake cables solid when doing a patch repair on a Panda twist beam spring pan.

You need to think about where that return current is going!

Correct

You have to think about the retun path

As long as the return path to welder earth is easier than any alternative than nothing bad will happen

Technically if all the earth's on the Panda are in good condition, you don't have to disconnect anything if you are using MIG welding and electrode wire is the normal positive,

Leaving the battery connected or not is going to give 100s of apposing views, personally I would leave it connected, it acts as a big sponge,

There are surge protectors you can buy that go across the battery terminals while welding, never used them, but shows even big companies expect the battery left connected


Cars have like the bmw 7 series E65 have upwards of 50 computers, it wouldn't be viable to disconnect everything

 

[DaveMcT]

I blew a motorbike alternator by welding on the frame. Battery was disconnected and welding clamp was on bare metal near the work area. I was lucky as the replacement alternator was not silly money. Ruined electronics would have scrapped the bike.

As a result, I disconnect battery and all computers when welding on cars. But I don't own anything with 50 of them.

Replacement sill panels are available for Panda 169. It's easier to replace the whole lot than try patching along the rotten edge. Inner sills and floor are a different matter as everything has to be fabricated. Few have the skills or the equipment for that.

A few years ago, I had my rear subframe grit blasted and zinc metal sprayed. It cost £80. Probably £100 today. I regret nor having it epoxy painted over the top as the paint I used was not cheap and has not lasted. Thankfully, a lanolin based anti corrosion protection seems to be working.