General Rear sill corrosion MOT fail

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General Rear sill corrosion MOT fail

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Jan 16, 2020
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Just been told MOT fail for corrosion on rear sill.
They said it requires petrol tank taking out to weld and it'll cost £300 🙄
Is this reasonable??
 
Just been told MOT fail for corrosion on rear sill.
They said it requires petrol tank taking out to weld and it'll cost £300 🙄
Is this reasonable??
In the past I have seen welders work very close to petrol tanks, but it is much safer to remove the tank and the garage's insurers would probably invalidate any claim so you can see why they would be reluctant.
Also having done Mot welding in the past, I have told customers "I would prefer being dead before cremation, not the other way around" ;)
 
When I had a similar issue on a Sporting

I removed the tank and towed it 1/2 mile to the welders yard..

He said :'that was a lot of effort..I always cover the tank in damp newspaper (papier mache)'

On going to collect it.. he said ..

I did the right thing..as he needed to go much further up.. towards filler neck...

Than originally thought


As always... spending money on Garage labour works against these old cars..


Luckily my welders were CHEAP..

@30 per hour.. no jobs more than £120
 
When I had a similar issue on a Sporting

I removed the tank and towed it 1/2 mile to the welders yard..

He said :'that was a lot of effort..I always cover the tank in damp newspaper (papier mache)'

On going to collect it.. he said ..

I did the right thing..as he needed to go much further up.. towards filler neck...

Than originally thought


As always... spending money on Garage labour works against these old cars..


Luckily my welders were CHEAP..

@30 per hour.. no jobs more than £120
I used to have a customer who was a professional "coded " welder etc. and taught it also. He was very derogatory about Mot welding , until I pointed out to him we don't all work on shiny new clean metal on a work bench, try doing a good job often nearly upside down on old rusty metal with traces of paint and underseal on it , in a draughty garage whilst worrying if the car was going to catch fire above you! In the old days I have seen smoke and flames coming out a metre away from where I was working as some bright spark in the past had stuffed a sill with newspaper to apply bodyfiller.
 
In the old days I have seen smoke and flames coming out a metre away from where I was working as some bright spark in the past had stuffed a sill with newspaper to apply bodyfiller.
Wax treatments can be "interestingly flammable too.

Personally, welding anywhere near petrol tanks terrifies me! Also worth considering that tin worm often works on the "iceberg" principle so you find that the corrosion has spread much further than you thought when you first looked at it and you need to take the tank out for access anyway! always worth making sure there's no carpeting anywhere near and watch out on more modern vehicles for expanded plastic fillers, (often looks like black polystyrene I think?) my Ibiza's got tons of the stuff!

While we're on the subject of welding it's worth mentioning that you need to be aware that for some years now many manufacturers have been using high carbon "high strength" steel in structural parts of the car. This lets them use thinner material without sacrificing strength thus saving weight. Unfortunately high strength steel becomes brittle if you attempt a conventional welded repair on it with the sort of plant typically available to the home DIYer. The weld, which looks fine when performed, will be very likely to crack after a while! Don't ask me how you identify whether that rusty inner sill or box section you're hoping to repair is made from HSS or "ordinary" mild steel though. So far hasn't been a problem for me as I mostly weld my old horticultural machines chassis and the very occasional "Classic" car. MOT repairs are "horrid"! As Mike says above, you often find yourself upside down under a manky old vehicle with cold wind and damp making it even more miserable and with welding made very difficult due to rust, paint, wax treatments and bituminous underseal etc. I have scars on my neck from dripping melted bituminous underseal! I prefer to use gas when doing this sort of work because MIG/MAG only really works on nice very clean metal (difficult to find when doing MOT repairs.) Luckily there's a "wee man" near me who hires a ramp in the corner of a large workshop specifically to do this type of repair. His welding is of the very highest quality and he seems to only have two prices £120 for "small" repairs - maybe patching a sill or box section - and £250 for bigger stuff. He does a far better job than I can manage in my driveway so I just hand this sort of thing over to him and keep the "fun" jobs on the cultivators etc for myself.
 
Wax treatments can be "interestingly flammable too.

Personally, welding anywhere near petrol tanks terrifies me! Also worth considering that tin worm often works on the "iceberg" principle so you find that the corrosion has spread much further than you thought when you first looked at it and you need to take the tank out for access anyway! always worth making sure there's no carpeting anywhere near and watch out on more modern vehicles for expanded plastic fillers, (often looks like black polystyrene I think?) my Ibiza's got tons of the stuff!

While we're on the subject of welding it's worth mentioning that you need to be aware that for some years now many manufacturers have been using high carbon "high strength" steel in structural parts of the car. This lets them use thinner material without sacrificing strength thus saving weight. Unfortunately high strength steel becomes brittle if you attempt a conventional welded repair on it with the sort of plant typically available to the home DIYer. The weld, which looks fine when performed, will be very likely to crack after a while! Don't ask me how you identify whether that rusty inner sill or box section you're hoping to repair is made from HSS or "ordinary" mild steel though. So far hasn't been a problem for me as I mostly weld my old horticultural machines chassis and the very occasional "Classic" car. MOT repairs are "horrid"! As Mike says above, you often find yourself upside down under a manky old vehicle with cold wind and damp making it even more miserable and with welding made very difficult due to rust, paint, wax treatments and bituminous underseal etc. I have scars on my neck from dripping melted bituminous underseal! I prefer to use gas when doing this sort of work because MIG/MAG only really works on nice very clean metal (difficult to find when doing MOT repairs.) Luckily there's a "wee man" near me who hires a ramp in the corner of a large workshop specifically to do this type of repair. His welding is of the very highest quality and he seems to only have two prices £120 for "small" repairs - maybe patching a sill or box section - and £250 for bigger stuff. He does a far better job than I can manage in my driveway so I just hand this sort of thing over to him and keep the "fun" jobs on the cultivators etc for myself.
I think it was on Vauxhall cars I first came across the HSS or what I called high tensile steel and gradually the information about it filtered down to us, I believe a different type of spot welder was required also. We also had a small one man business who only did gas welding and said Mig was for cowboys as far as he was concerned, he did excellent work and no one could touch him on price, sadly he passed on. Mind you I recall he had the fire brigade around a few times!;)
 
Yes, I think you're right. Not just any old spot welder either. Current and duration very important I believe. Easier and safer to just to leave it to someone who knows what they're doing.
Thanks for all the advice! I'm planning to make sure everything is easy to remove for the garage so they can't sting me for more money for "this clip snapped","the fuel pump lock ring broke", "that bolt was rusted solid".
Is there a guide or photos of what needs loosening prior to taking the car in for welding?
 
Thanks for all the advice! I'm planning to make sure everything is easy to remove for the garage so they can't sting me for more money for "this clip snapped","the fuel pump lock ring broke", "that bolt was rusted solid".
Is there a guide or photos of what needs loosening prior to taking the car in for welding?
So if you are going to remove the fuel tank and tow the car in, then tank out any hoses or wires safely secured and taped off, battery out, seats out if near rust area, any plastic panels, sill coverings etc. out, any suspension mounts, bolts etc. that may need to be lowered to give access to welding area but cannot be removed to tow vehicle safely freed off so nothing seized that will take longer for the garage to remove.
Finally wire brush down to bare metal the total area and just beyond any the MOT tester wants repaired, including tapping around to make sure there is nothing he has missed due to tank etc. blocking his view, so welder has good strong metal all around where he is patching.
I always used a twisted wire brush on an angle grinder to remove any paint and underseal etc. rather than an angle grinder disc as you can make the metal cleaner but thinner by accident , taking away good metal with the rust.
 
I always used a twisted wire brush on an angle grinder to remove any paint and underseal etc. rather than an angle grinder disc as you can make the metal cleaner but thinner by accident , taking away good metal with the rust.
Yup I like twisted wire brushes too but I've also used this sort of thing to great effect: https://www.ebay.co.uk/itm/16500203...DJQqq+tlQ8aeOGkftefgr4yj0=|tkp:Bk9SR5zHmeXkYA Removes paint and light rust very quickly without abrading away the sound metal.
 
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Unclipping the filler neck is a muddy mess..and fiddly

Mine were not on properly.. So it was an opportunity for improvement


IF the tank is showing empty.. no real reason the remove the pump.. just uncouple the electrics and lower the tank.

Its just another few KG to support.. pump and 3 litres of fuel

The tank will be well away from the car for welding..

Handbrake cables are in the way too IIRC

Interior trim wasnt an issue.. but might be worth lifting out the under seat 'padding' and unscrew any plastic trim under there

At £60 an hour labour.. you can save a fair bit preparing and reassembling yourself

IDEA: any other local corrosion mentioned?

Could be cost effective to deal with that NOW.. while you are poking around and stripping trim :)



A word of caution...

My 1st punto 188 was.. a very cheap.. scabby example..

The floor was bad.. I got All of the Advisores welded..as well as the Fails

12 months later..it was WORSE I scrapped it.

This was common corrosion ( factory underseal cracking..then trapping roadspray AND SALT)

If youve had this car for years..you will know the levels you are at :)
 
Thanks all! I won't be removing and towing just making sure the lock ring on the pump comes off without damage and heating up clips and unclipping the bits I can as well as wd40 soaking on all the bolts that need to come out.
I will try and clean up as much with a wire brush as I can while I'm under there!
 
and unclipping the bits I can as well as wd40 soaking on all the bolts that need to come out.
You could make a better choice of penetrating oil. WD40 is an excellent product for many general purpose applications, especially for dispersing water/moisture from the likes of ignition HT components - guess what the WD stands for? In my experience you'll get a better penetration with something like Plus Gas (my "weapon of choice") or one of it's competitor's like PB Blaster (I'm sure other forum members will have their favorites too.)
 
I've just had a look under the car at the suspension component mounting (inner sill, side of fuel tank).
Yes there is surface rust but it looks no different to the area on the other side of the car!
I'm not 100% sure of how trustworthy this garage are (they already charged me £63 for a new tyre which I could buy myself for less than £40 for a "lump" on the old one which I hadn't seen when I checked them).
Should I take it somewhere else to look at it?
 
Well I would get a second opinion. Also if spending this much my thoughts are can you get another car for a similar outlay. You might be able to find somewhere to keep this car as a donor for other parts. Not an easy decision ever!
 
Where are you based? Could the Darby allude to Derby perhaps? Maybe there's a forum member near you who could recommend a trusted garage if we knew for sure where you are.
Regarding the tyre price, it depends very much on the brand and quality. For a top of the range Continental, Michelin, Good Year - in other words a really big name - that price looks not bad. On the other hand if it was a name noone has heard of then yes, I'd agree, you may have paid a bit over the odds. Prices are so difficult to keep tabs on these days though, something bought last week is almost guaranteed to cost more this week!
 
Where are you based? Could the Darby allude to Derby perhaps? Maybe there's a forum member near you who could recommend a trusted garage if we knew for sure where you are.
Regarding the tyre price, it depends very much on the brand and quality. For a top of the range Continental, Michelin, Good Year - in other words a really big name - that price looks not bad. On the other hand if it was a name noone has heard of then yes, I'd agree, you may have paid a bit over the odds. Prices are so difficult to keep tabs on these days though, something bought last week is almost guaranteed to cost more this week!
The Darby did indeed allude to derby originally but now resides in the north west in Wigan.
The tyre they put on is bog standard autogreen sportchaser cs2.
I'd welcome any suggestions for a decent mechanic/welder near me!
 
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