future

Sills – Stop the Rot

An issue I’m seeing and reading about a lot more over here in the UK and Europe are increasing numbers of transaxle cars failing the yearly MOT’s due to the dreaded tin worm eating away at our sill. This is not restricted to the 924’s where by early cars chassis were not galvanised and later ones ‘if I am correct’ only had galvanised floor pans which was carried through to the early 944 N/A’s.

My 87 952 is no exception – I’ve just had to spend £700 on having both the outer and inner sills replaced along with repairing the bottoms of the front fenders which again had rotted right through.

I don’t have any pictures of the repairs on my car for you yet but hope to take some soon but in the meantime I came across this white N/A 944 on the UK Porsche GB forum:









As I spend quite a bit of time down at the local Porsche breakers yard what is even more worrying is that it appears that the later 968 models are suffering this ‘tin worm’ epidemic worse than the 944’s. This is mainly due to the fact that the 968 has plastic rocker covers letting dirt and moisture build-up resulting in a massive bill just round the corner!?!

Obviously you guy’s down under and stateside do not see this as much as we do but maybe this is a good opportunity to start a thread about how to prevent and take early action before more car head to the Porsche grave yard.

Many people over here in the UK are filling their sill with Wax Oil via the inner B-Pillar vent. I’d love to here other people experiences on this subject as before long this is a problem we will all encounter and this will result in more cars heading to that very grave yard.

The white 944 N/A personally looks way to gone for me to want to entertain repairing so I can only commend people that take on such huge tasks on cars worth so little in value which is obviously far superseded by the love the owner shows for their car and the Porsche marquee.

So to this effect I thought it would be a good chance to start a thread which is a little different to the norm where by hopefully we can all share our experiences and keep our great cars on the road for many years to come

Fishey

Never seen this issue here on American cars in all of the ones I have worked on that where not wrecked/repaired. Hell its rare to find any rust on the cars sometimes in the rear fenders but never like that... Thats just insane.

future

Yes it's everybody's worst nightmare but this car is by no means an exception.

Heres another white one, again with exactly the same problem with some good detailed pictures:
http://www.pbase.com/tr7v8/porsche_repair_pics

Dan87951

Wow thats crazy.. I have never seen a 944/968 rotted that bad ever. My first 951 was a daily driver and was driven year around by the PO who was the first owner and I drove it year round. The only evidence of rust was a small 2"x4" strip on the bottom driver side front fender. Did they not under coat these cars in your country from the factory?

MAGK944

Constant damp weather, condensation inside the sills and the road salt they put on the roads there will cause this. Happens a lot in the UK, rarely seen on US 944's, never seen here in FL.

Once you fit those new sills on give the inside a good coating of Waxoil and make sure the sill drains are clear.

mikeroz

Mark,
I would agree with you on this body rot on Uk and Weste´n European cars.
My 1990 turbo went in for body work just before it went into Jon Mitchell for its 3.2 motor. It required outer sill work and bottom fender replacement just like you reported.

I live in Germany and I've studied the pictures for many an ebay advert for second hand fenders (wings) here on ebay.de and so many of them are rusting or completely rusted out on the bottom where they wrap round to the bottom of the sill.
I noticed bubble rust appearing on my sills about 12 months into my cars ownership and decided to repair it "properly" (by that I mean best I could), the sills had been filled with grp down their entire length!!!! The metal has now been cut back to good clean stuff and new steel offered up and welded in place.
I was advised against a replacement sill - something that I´m still not certain about; whether it was the right decision??? If they do go again then I'm getting genuine Porsche sills and I´m going to replace the whole lot.
As for whether something is too far gone; only the owner can answer that. In my opinion anything is repairable (with the exception of very severely twisted monocock chassis perhaps) it just depends how attached you are to the car and how much cash you're willing to sink into it to repair it. Then it's a case of finding someone with the right skills and professionalism (by that I mean care and attention and pride of workmanship) who can do the job correctly without charging you £100/hr. There are lots of great guys in the classic car restoration business back in the UK who are capable of doing this sort of work.
Regards
Mike
PS I love your new web site. Keep up the good work you and Beni!!!

future

Hi Mike, thanks for the comments and compliments mate.

Well I’d like to say I glade I’m not alone on this one but of course that isn’t really the truth.

Yes mate, I purchased a front fender from ebay and thought I’d got a good deal at £56 but when it arrived it was just as rotten as the one on my car I wanted to replace. I ended up having a new plate welded onto the bottom to replace what was missing due to rust. This was the first time I had ever removed a front fender and I was simply amazed at just how heavy they are – Off-topic, I know but all wanting to save front end weight, hell just change those front fender to FRP and keep the stock hood!

Anyway and more to the point, I went down the complete inner and outer sill replacement but had them fabricated from scratch rather than go for the oem patent parts and used a thicker gauge steel which I’m hoping will provide another 20 years rotting trouble away.

Great advice mate … I’ll go and check out eBay and see if there are any more pictures I can post highlighting this problem!

mikeroz

Also if you live in the UK and wish to protect your car from the elements then its worthwhile:

1. Injecting cavity wax into the sills and also coat liberally with wax the inner area at the base of the wing and the area at the leading edge of the floor pan. You need to inspect these annually and keep on top of them especially if it is your daily driver.

2. Remembering not to put your car away wet in your garage and then leave it for a few days, weeks or even months. Instead make sure it's dried off and ensure the garage is completely free of damp.
3. If you can get a dehumidifier. It’s infinitely cheaper than the cost of repairing rust and it´ll give you a reassuringly warm feeling inside too.
4. Try and avoid driving the car in the wet. Get a daily driver that you're not going to cry over if it rusts to bit. (Get a 2nd hand Merc, BMW, VW, Audi, Saab, or Volvo and you're unlikely to get any rust anyway).

Peter Empson

The photographs above are of my car and show the state it was in at the start of the year

The rust is particularly bad on the side pictured due to a less than brilliant repair over 11 years ago (before I owned the car), the other side was in better shape. This car has been driven daily and is kept outside in all weathers.

The work has been a little more extensive than intended, but the up side is it will come back much, much lighter than before and I'll be confident it is now completely rust free. As soon as it's back a super charger will be going in, so the poor thing wont know what hit it

There's more pics on my website if anyone's interested here

500

Very sobering, especially given that these cars are so much less rust-prone then their contemporaries. What is sad is that when people part cars here that have very solid bodies, the bodies often end up being carted away for scrap.

My project is a 147000 mile daily driver and I had it stripped to a tub and have scoured every inch and peered with flashlight into the sills and all other nook and crannies and there was no rust (thankfully).

Peter, you are to be commended for doing such a thorough job fixing yours.

Peter Empson

The funny thing is I got my engine and gearbox from an S2 that was scrapped due to similar amounts of rust. I just have so much time invested in the car (what with the engine swap and the suspension setup etc) this was the most logical way forward for me.

tommye

From what I've seen, rust is more of a problem on the late 944:s, rarely seen on earlier models (series 1). Rumour has it that the galvanizing process was changed somewhere along the way....

Tommy

Peter Empson

My mechanic believes that the sill trims on Turbo's and S2's are responsible for a lot of corrosion as the dirt and salt gets stuck in there.

future

Hi Peter, firstly great little website mate and congrats on keeping your car on the road.

Can I firstly ask who was it that did the repair work for you? The work looks first class and dare I ask how much has/is it costing and is your car back on the road now?

From my experience and from looking at many cars in the UK it tends to be silver and white cars that are affected the worst! I do know that silver paint is actually porous and if left un-waxed for periods of time, rust soon sets in.

By looking at the extent of the rust on your car I would estimate that this has been an ongoing problem for some 8 to 10 years and I notice that you state that your car lives outside all year long so how long have you actually owned it?

The rust on my car was not quite as bad as you have experienced which I'm sure is part down to having the car dry stored when not in use.

Did your front wings have rust present at the bottom edge of the wings like mine?

How much of the interior are you actually going to put back in after completion?

Cheers,
Mark

Fishey

US bodies do have that crap they sprayed on for shipping wonder if thats a big difference maker.