to all volvo 850 owners hidden rust please read
 

Following on from the thread about the rust hiding behind the rear wheel arches by diplomat2.6, I think all 850 owners need to read the article in the sticky about hidden rust. It is one of the last articles at the moment. The reason I mention this is because this is becoming a real issue, as now after 22 years or more, this hidden rust problem is just starting to rear its ugly head in a big way. The rust is such that it can be hiding for years without anyone really noticing, but only evident when the plastic liners are removed.

If these cars need to survive the next generation it needs tackling now. Most should just get away with grinding back and rust treatment, but if left for a couple more years will scrap most of these cars off completely.

Be warned!

Heck, that's scary! Does the same problem afflict S/V/C70 cars too? Our S70 has just turned 21, and I must admit that I've always gone along with the belief that these cars simply don't rot, apart from the rear exhaust hanger. Now I feel a bit of an inspection might be in order.

To be frank, if I found corrosion to the extent of the rot found in the other thread on the same subject I think that it'd possibly be curtains for the car.......but hey, should I worry? It passed the MOT just six weeks ago.

Jack

The V70 doesn't seem to suffer as bad, as I have managed to have a good look at a few, but they are potentially the same car, so who knows. Maybe they found an error in the galvanising and sorted it.

The car will pass its mot because it is hidden behind the plastic shield. Once it gets bad enough to fail an mot I think the car would be scrap.

I must admit, the car in the other thread is as bad as I've ever seen. If you read the article in the stocky you will see what I had to weld up but it didn't spread under the car, so I managed to save it, but it's not a job I enjoy doing. All 850's need to be inspected and treated now before it's too late.

I can recommend removing all the wheel arch guards front & rear and then treat with a wax treatment diluted with clean oil-- luckily both my cars a’97 V70 & ‘88 240 have been rust free. The 240 didn’t have rear guards from original but it does now.
Remove from time to time and treat again.
Bob.

Most 850's will need the grinder on it first 😃

This is very sound advice. I have a 1997 v70 t5 and had an absolute mare with rust. My car thankfully didn't have it too bad in the rear wheel arches. However, the sill covers completely hide the sills and when removed you would not believe what they were hiding and it had just passed an mot. As it turns out the clip holes for the sills double up as drain holes and these had been clogged for what must have been a decade because the rust was horrendous. I had the car fixed because I love it but the above advice is very sound indeed.

Gareth

As I understood it, the way the plastic wheel arch covers are affixed to the shell is better on a V70!?? I drive mine in Summer nowadays, but through the Winters, whichever car I've driven I always pressure wash underneath and wheel arch inners every week without fail. It helps a lot imo!

The problem is not muck or water getting behind the liners, it is a production problem that seems to just rust behind the plastic. When these liners are removed there is little in the way of debris. No pressure washing under the arch will make any difference, as all you are doing is cleaning the lining. This will help the underside though.

Pray tell how it is rusting if nothing is getting behind the liners. You need moisture and air to cause the rust. You also need some sort of debris to abrade the factory rust protection and galvanisation to get down to bare metal before it can rust.

Of course the problem is muck and water getting behind the liners. That becomes even more apparent when you see they don't sit perfectly flush and there is a gap between the liner and the top of the arch.

You are spot on though that it is a big issue and simply rinsing the liner wont help. It does need regular treating with a rust preventer.

Whilst in this case (bad design of splash panels) p ressure washing will not solve the problem - more generally it helps a lot and goes a long way in preventing the lethal cocktail of salt/mud which kickstarts the corrosion process. Anybody who's owned a gamut of old Fords will know exactly what I mean.