2008 ML550 Power Steering Reservoir Seal
Thread Starter
Junior Member
Joined: Oct 2014
Posts: 45
Likes: 4
From: Calgary, AB
2008 ML550, RotorWay JetExec
2008 ML550 Power Steering Reservoir Seal
Does anyone know if there is a better seal that goes between the power steering pump and reservoir tank? I had to replace the tank and put on a new seal. It leaked. Again!
When installing this new tank, I noticed one of the bolts (of course, the one most difficult to get at) would not engage with the pump housing very easily. I took the tank off and drilled out the 3 steel sleeves with a "K" drill. Then all 3 bolts engaged easily, meaning the nipple on the pump and the outlet of the tank were aligned properly.
But even with all that care, and a new URO seal, it leaked.
So, does anyone know of a better sealing mechanism? I am considering using two M3 x 16 mm (22mm OD - 16mm ID) O-rings instead of the seal. But I don't want to have to drain the rad and the PS tank again...... For the @#%$ time!
Thanks if anyone replies.
When installing this new tank, I noticed one of the bolts (of course, the one most difficult to get at) would not engage with the pump housing very easily. I took the tank off and drilled out the 3 steel sleeves with a "K" drill. Then all 3 bolts engaged easily, meaning the nipple on the pump and the outlet of the tank were aligned properly.
But even with all that care, and a new URO seal, it leaked.
So, does anyone know of a better sealing mechanism? I am considering using two M3 x 16 mm (22mm OD - 16mm ID) O-rings instead of the seal. But I don't want to have to drain the rad and the PS tank again...... For the @#%$ time!
Thanks if anyone replies.
Super Member
Joined: Nov 2019
Posts: 648
Likes: 144
From: Yeast Coast, Canada
GL550 X164
Does anyone know if there is a better seal that goes between the power steering pump and reservoir tank? I had to replace the tank and put on a new seal. It leaked. Again!
When installing this new tank, I noticed one of the bolts (of course, the one most difficult to get at) would not engage with the pump housing very easily. I took the tank off and drilled out the 3 steel sleeves with a "K" drill. Then all 3 bolts engaged easily, meaning the nipple on the pump and the outlet of the tank were aligned properly.
But even with all that care, and a new URO seal, it leaked.
So, does anyone know of a better sealing mechanism? I am considering using two M3 x 16 mm (22mm OD - 16mm ID) O-rings instead of the seal. But I don't want to have to drain the rad and the PS tank again...... For the @#%$ time!
Thanks if anyone replies.
When installing this new tank, I noticed one of the bolts (of course, the one most difficult to get at) would not engage with the pump housing very easily. I took the tank off and drilled out the 3 steel sleeves with a "K" drill. Then all 3 bolts engaged easily, meaning the nipple on the pump and the outlet of the tank were aligned properly.
But even with all that care, and a new URO seal, it leaked.
So, does anyone know of a better sealing mechanism? I am considering using two M3 x 16 mm (22mm OD - 16mm ID) O-rings instead of the seal. But I don't want to have to drain the rad and the PS tank again...... For the @#%$ time!
Thanks if anyone replies.
Thread Starter
Junior Member
Joined: Oct 2014
Posts: 45
Likes: 4
From: Calgary, AB
2008 ML550, RotorWay JetExec
I discussed this with a hose and seal specialist yesterday. He suggested a Buna-N O-ring, again M3 x 16mm. Two of these would be a little wide for the slot in the nipple, so I backed up the Buna-N with a M2 x 16mm regular O-ring (closest to the pump). This arrangement was much "stiffer" when engaged with the tank than the factory seal, meaning it should seal better, especially with the Buna-N material.
If that does not work, it will be Permatex 82180 Ultra Black Maximum Oil Resistance RTV Silicone Gasket Maker!!! Thanks expl0rer. In this case, the factory seal is inferior.
If that does not work, it will be Permatex 82180 Ultra Black Maximum Oil Resistance RTV Silicone Gasket Maker!!! Thanks expl0rer. In this case, the factory seal is inferior.
