Concerned about corrosion

[TTM]

Good morning Gentlemen,

The other day I was shamelessly staring at the underpants of a friend's pristine, undamaged 60k miles '90 turbo and we found out many spots of corrosion just about everywhere near main welding spots - along front side members - but also in places far from welding spots such as around the screws fixing the front cross member.
Corrosion appears to develop even under the main black "coating" the shell is covered with everywhere under (we call this coating "blackson" in French, not sure of the English term, sorry !)

If such corrosion happens on a garage queen it concerns me that 944 owners who drive theirs on a regular basis and in all kind of weather may go through unpleasant suprises at some point.

What do you think ?

 

[Fen]

Mine was really not that bad. I stripped a lot of the stonechip protection off the sills and it was fine underneath. I also went along the section that sits behind the black plastic sill protectors and it was again not bad but cetrainly worth doing something with. I think I posted a similar warning in fact. One of my drain holes was blocked and I really think everyone shpuld check that theirs are clear as I suspect that is the major cause of the rot some cars are developing under the door rear corners. Around my crossmember mounts was absolutely fine - I cleaned them up and painted them with Hammerite though - same for the sills, the bit behind them with the drain holes in, the bottom of the front wings, the jacking points (where the black underseal was coming off in sheets and there was surface corrosion beneath) and the rear beam and swing arm mounts. I will be spraying Waxoyl in the sills very soon to complete the job.

 

[carlmthompson]

I guess they all do!

Mine has many reciepts for "Tectyl 506", which is the black stuff we refer to as underseal.

Despite this, the jacking points especially still have surface rust on them! Most of this will be because we use salt over here to clear ice and snow - pretty stupid considering it's not very comatible with steel!!

 

[944Turbo]

Actually I am fairly certain the black stuff under our cars is actually white. Certainly on both my '44s if you give it a good clean it it goes white not black. It is also a lot more rubbery than the nasty black underseal they used to use on British cars in the 70's. Provided they are well washed (especially in the winter, underneath to get the salt off) driving should be no worse than sitting in a normal garage condensating. However if you have a heated / dehumidified garage then that would be the better bet.
Tony

 

[944Turbo]

Also the more 'used' cars are more likely to have some oil spread about the underneath - from spills from oil changes, minor leaks etc. this is also going to help with corrosion protection.
Tony

 

[Diver944]

ORIGINAL: 944Turbo

Also the more 'used' cars are more likely to have some oil spread about the underneath - from spills from oil changes, minor leaks etc.

I knew there was a reason why I make so much mess when I do this [] I firmly believe my garage floor will NEVER rust

 

[TTM]

ORIGINAL: 944Turbo
Also the more 'used' cars are more likely to have some oil spread about the underneath - from spills from oil changes, minor leaks etc. this is also going to help with corrosion protection.
Tony

Very true.
I will probably not replace that leaky oil pan gasket after all []

 

[Fen]

Maybe mine is pretty good after having the entire contents of the sump sprayed over it at high speed... []

 

[John Sims]

ORIGINAL: 944Turbo

...... should be no worse than sitting in a normal garage condensating. .......

Tony

It is for this very reason that Beaky's new home is going to have an insulated floor slab and plenty of air bricks around the outside at low level.

 

[John Maddox]

I have heard on at least two occasions that the concrete screed in most domestic garages which our cars stand on (including mine) actually let off some low level corrosive vapour which over time can increase corrosion.

Don't laugh but my Porsche sits on an old carpet we replaced because of this !! Sad but true.

 

[carlmthompson]

Mine sits on the old Red Carpet from the Gosforth Park Marriott Hotel[]

 

[John Maddox]

I'm not alone then !!!! My wife thinks I'm barking...

 

[Guest]

A lot of cars of the age most 944's are have had some bodywork done, replacement panels with no stonechip, waxoyl, seal sealer etc. A bad winter will deposit salt laden mud which which rust from inside out. My other half had a fault free Merc untill F! in April a few years ago. Being towed on and off a Silverstone bog deposited shit I didn't find until May this year.

Sills went, both front wings and rear arches. Took wings off and recognised that colour of mud! Would love to sue Bernie - rip off weekend plus wrecks the car!

With his car, and mine - going to steam clean (not engine) once a year, get on ramp and sort any problems before they become nightmares. Would recommend this, and, when changing oil, chuck contents of sump everywhere.

 

[sib8292]

ORIGINAL: John Maddox

I'm not alone then !!!! My wife thinks I'm barking...

This is a normal opinion by a wife imho...