Under seal
 

I'm considering re under sealing my 940. I'm thinking about using waxoly however I'm open to opinion on this. One thing I can't figure out is how you remove the plastic trim which covers the inside of the wheel arches, if anyone has any pointers that would be great.
Thanks Luke

940 tdi auto 1995
 

hi ive been wax oiling my car a few years now its not bad but it did not stop the rust completely i ended up paying £ 400 to have the rear cill both sides and jacking points re welded plus cross member . wax oil builds a hard crust which spits and water gets in then is sealed by more wax oil then rust process starts . last year i payed a garage £108 to spray the under body with a rock oil type oil/grease its still taco now after 8 months garage says it lasts years and years .so if you have no rust at moment may be thats the way to go only my personal experience !

Old engine oil is better than waxoyl for the above reasons.

Underseal you can paint on is good too.

Dinitrol in the seams/sills/box sections is very good with an air gun application.

I have heard positive things about por15 too and someone else recently did their 940 bit I can't remember what they used (I'm sure they will be along shortly).


The key to it all is in the preparation, you need to remove any old broken underseal, steam clean all the filth off and give it a couple of days to completely dry. It is definitely a summer time job to do it properly.

I can vouch for ATF being a good rust preventative! When i first got my 760, it had a leaky extension housing covering the floorpan from just in front of the B-post back. The only small amount of rust i've had to have sorted has been in front of this point - behind it is still near enough perfect, despite twisted jacking points from some idiot jacking the car on a hill!

Also a little more anecdotal, some years back i made some tracking gauges out of box section and for one reason or another, after being damaged during my move here, they ended up outside in all weathers.
I wanted to use some parts from one recently so sprayed it with a mix of acetone and ATF-U to release the rusted nuts/bolts. The rust went and has stayed gone on the bits that were sprayed!

I'm assuming you mean the wheelarch liners here. So had a quick look at my 960[see no reason why they'd be different on a 940] From what I can see for the front liners there is a bolt or nut onto a captive bolt ahead of the wheel inboard of but roughly in line with the top edge of the front bumper then if you look into the wheelarch from the side of the car just aft of the wheel there's another bolt/nut holding it to the inner wing and a third one on the rear face of the arch.I couldn't see/feel any others but I didn't remove the wheel to see if there are any more that the wheel might block the view of.Once these are removed it looks like a case of wiggling the arch liner off the wheel arch/wing lip.The rear liners are the same but I could only see two bolts/nuts one on the front face of the arch and the second on the rear face.HTH.

Thanks dippydog for the advice about removing the liners. After a good wipe down I too can see the bolts so should be simple enough. Thanks guys for the recommendations on underseal. However I'm slightly torn now with what to use the waxoyl doesn't sound great at all. And I've heard mixed reviews before regarding engine oil although the logic makes perfect sense