W124 1989 300E Rusting jack point. (Expletives removed) - PeachParts Mercedes-Benz Forum

whunter · #1 02-11-2006, 01:02 PM

Quote:

Originally Posted by Tassie

My 1989 300E is in perfect operating order and absolutely no rust until I recently inspected the 4 jack points.

I have posted a few pictures of the LF jack point (the worst one) and would be grateful for information on the MB body structure around the jack points, assessing the damage, stopping the corrosion, and then repair.

Necessity dictates that I have to do as much as possible myself and limit the most complex work to others.

Many thanks,
Paul

Request current pictures, how is the repair holding up to Canada winter?
Any special advice on this repair?

Tassie · #2 02-13-2006, 10:37 PM

Well, in the end I chickened out doing the repairs myself after losing confidence with the products from the local auto supply store and also not having the right environment to do the job properly as it was getting too cold outside. So I prepared the jack points as shown and did what I thought was right for prepping against flash corrosion. I also called a few autobody shops and then choose to take the vehicle to the only local shop that used OEM (Glasurit) supplies. My stipulation was that I never wanted to return to the shop with the cost chasing that requirement.

However, I'm not sure that I received what I wanted.....take a look. Any comments?

Appreciate any thoughts on next steps.

whunter · #3 02-14-2006, 01:24 AM

Exterior is nice.
Interior looks like naked metal.
You could attempt POR15 treatment, but you risk making a mess of the exterior paint.
Several members use bearing grease inside the tube + a rubber plug/cap to seal each tube. With the correct cap/plug it looks good, and will out live the vehicle, the only issue becomes heat = poor cap/plug seal drooling/leaking grease during hot summers = visiting Texas, Mexico, Florida, southern California, etc, etc.
In Canada you should not have heat issues, so I would suggest a light coating of spray chain grease = farm equipment or motorcycle shop should have it, the cap/plug may be more difficult = to find one that fits correctly, and you can buy in groups of eight or more for spares.

Please do NOT pack them solid with bearing grease = in (Canada) sub zero conditions it becomes very hard, making the jack point unusable.

Tassie · #4 02-14-2006, 10:44 PM

I still have the original caps. I left them off as others were saying that the caps only trapped moisture inside and this was the cause of the corrosion in the first place. All 4 jack points had grease remaining with 3 of the 4 having corrosion at various stages. The corrosion was limited to the first inch or so inside the tube and the worst corrosion appeared to be at the outside edge.

I'm worried that putting the caps back on would start the process over again. Your idea of putting the POR 15 on the new corrosion seems logical although, as you say, care would have to be taken to avoid damaging the paint. I hope this would stop or substantially slow the corrosion.

Thanks for the response! I also appreciate all the others who have guided this repair.

Paul

donbryce · #5 02-15-2006, 10:57 AM

I really do think that you should replace those caps. In place, maybe with a bit of grease or dab of silicone to seal them, and assuming you have now sealed the tubes on the inside, the only moisture in there would be condensation....and we know that it takes warm/cold surfaces to produce this, highly unlikely inside a rocker panel IMO. Leaving them open just gives the water a 100% chance of getting in, and in our winters, you'll maybe get some salt in there with it too.
If you're worried about grease stiffening up in the cold, just get a small container of snowblower grease, the kind they use in the differential, I think it's called Alvania or something like that. I used it on the regulator gears and tracks of two of my Mazda power windows to keep them from slowing down in cold weather due to stiffening.

1badav · #6 02-25-2006, 05:28 PM

How about doing both. I think whunter's suggestion of the spray chain grease is a good idea, but what about combining that with putting the caps back in with one minor modification---center and drill a tiny hole in each cap so that water can wick out if there is condensation that develops or any water happens to "splash" up in there. Then I would think you would have the best of both worlds. Just a thought.

Zeus · #7 02-28-2006, 03:55 PM

I have the same problem with my jackpost holes on my 300E. Bloody road salt.

I have not yet tackled them, but thanks to all for the info here. I'll likely do something similar. When I first noticed them rusting a couple of years ago, I had the underbody chassis undercoated and asked the guys to spray a bit of undercoating (essentially oil) into each jack hole. It worked wonders for slowing the corrosion down.

I'd maybe echo the recommendation to spray a bit of tacky oil into the inside of each tube and then replace the caps. I wouldn't drive it around without the caps in. All IMHO.