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I found oil in the base of the boot of my SL63 R230. I am sure it is hydraulic oil from the vario roof but unsure which part is leaking.
Lately the roof motor has been making some noise which was previously relatively quiet.
Any idea where to even suspect the cause of noise and where the leak might be from?
There is no evidence of hydraulic leak on the floor where the car is parked Previously the fluid was way below the “+” mark. Mechanic had it topped up to just below “+” but after a few roof operations, I may have noticed the fluid going down a bit. Or maybe I did not accurately see the exact level post top up. Hydraulic fluid was found coating this cloth covered wiring. I have since wiped it dry as best as I can.
This picture shows an hydraulic cylinder which could be leaking. Have a close look at the point where its rod passes through the outer seal and look for evidence of leaking oil. (It should be completely dry.)
I suppose if hydraulic fluid is ONLY found in the boot and nowhere else, then we can possibly conclude that the leakage is coming from the pump and its immediate vicinity lines in the boot and not from the hydraulic cylinders?
Left and right trunk tubular frame lock hydraulic cylinders
When the trunk lock cylinders (which are in the horizontal plane) fail the leaking fluid (from both cylinders) flows down into the bottom of the trunk, pooling near the rubber drain hole. You will need to remove the trim panels on both sides of the trunk to establish which cylinder(s) is/are leaking. Best to replace the cylinders as a pair. While you have those panels off, you will also be able to check the L and R roof open/close cylinders, which also lie horizontally, but are closer to the front of the car. The two load assist cylinders are harder to find, but the fluid from them (if they are leaking) won't be evident in the trunk.
Trunk Trunk Lid Drive Cylinder (located left side) A230 800 13 72
This cylinder rotates a shaft that lifts the trunk lid from the rear of the car. It is the easiest cylinder to access. Part number A230 800 13 72. You can have it repaired (new seals) rather than buying a new or used cylinder. Top Hydraulics (Top Hydraulics.com) or Cabriolet Hydraulics (https://cabriolethydraulics.com/products-services) will do the rekit. Simply a matter of removing the cylinder and sending it to either company. Ensure your mechanic uses the correct hydraulic fluid (MB genuine only; not other types as described elsewhere in forums). Provided the valve body near the pump is plugged to prevent dirt entering, you will still be able to drive the car while the cylinder is away for repair.
Your mechanic should also check the other cylinders for leaks, particularly the front lock cylinder (above front of hood lining, near rearview mirror) and the two trunk tubular frame lock cylinders I mentioned in an earlier reply; otherwise you will have the same problem with fluid on the trunk floor after the trunk lid drive cylinder is refitted.
I did ask the mechanic if he is checking the rest of the cylinders for leaks and he said it would cost me more labour charges if I wanted him to do that on top of replacing the leaking part.
So I thought I’d just leave it at that, and if it ain’t broken, don’t fix it?
Or do you think it is best to do a preventive check up? Will cost more money for labour and if they are all working fine with no leaks, I guess it will just be a waste of money on my part.
Trunk Trunk Lid Drive Cylinder (located left side) A230 800 13 72
This cylinder rotates a shaft that lifts the trunk lid from the rear of the car. It is the easiest cylinder to access. Part number A230 800 13 72. You can have it repaired (new seals) rather than buying a new or used cylinder. Top Hydraulics (Top Hydraulics.com) or Cabriolet Hydraulics (https://cabriolethydraulics.com/products-services) will do the rekit. Simply a matter of removing the cylinder and sending it to either company. Ensure your mechanic uses the correct hydraulic fluid (MB genuine only; not other types as described elsewhere in forums). Provided the valve body near the pump is plugged to prevent dirt entering, you will still be able to drive the car while the cylinder is away for repair.
You will generally find other cylinders leaking if one starts to leak, but because the trunk drive cylinder is easy to access there is no problem just doing the one cylinder. There may be a freight cost consideration if you need to send a second lot of cylinders away in the future.
I have been assuming you have an R230, but you profile shows you as driving an R129, which has adifferent cylinder configuration.
I also see that you are in HK. There are a couple of specialist MB vario roof cylinder repairers in Australia, but you may also have some in HK or on the mainland. If not, I would still recommend sending the cylinder to the US for rekitting.
Hi yeah, I have just updated my profile. I used to have an R129 but now I drive an R230 here in Hong Kong.
in the future when I suspect any of the cylinders leaking, the problem with removing them and sending them overseas to be rebuilt is that I have to get the mechanic to agree to have the car parked at his garage whilst waiting for the cylinders to get back... But as for the cylinder number 300, he did not give me an option to have it rebuilt.... only to buy a new one from Mercedes-Benz and install it......
As I mentioned earlier, a couple of small plugs can be fitted to the valve body while the cylinders are away for repair. There should be no extra labour for this as the pump/valve body needs to be lifted up anyway to remove the 2 hydraulic lines for cylinder #300 (your diagram). That way you can take the car away from the mechanics workshop while the cylinder is out. I don't know what you will be paying for a genuine replacement cylinder, but you should find repair, including freight, is far less than 1/3 of the new price. It is highly likely other cylinders will leak in the future or are already leaking (there are 8, plus roll bar cylinders). Therefore you will save thousands of dollars if you have cylinders rekitted by a specialist rather than replacing them with new ones.
Hopefully this helps someone - The hydraulic pump manufacturer HOERBIGER uses AeroShell Fluid 41 in the pumps. The Mercedes sales and accounting department don't want to sell you the o-ring rubber seal or fluid separately and rather sell you the whole pump. Luckily BMW uses the same pump manufacturer and sells a kit which includes the rubber o-ring, coper washers, and about 200ml of the fluid. Lookup BMW part number: 51247202869 (available on FCP, ECS Tuning, BMW, EEuro, BMW dealer etc.). If your leak is in the the cylinder/plunger, that is available separately from BMW as well, see part number: 51247202868 but double check that yours is the same length/style.
Hi Cdn_s55amg,
Thank you.
The problem with Happy Happy's R230 is with the convertible roof cylinders/rams (not his convertible roof pump). His car will not have a trunk ram that opens and closes the trunk in the traditional way. There are three trunk lid rams associated with the convertible roof on R230s. Two lock the front of the trunk lid after the roof has been closed or opened, and the other lifts the rear of the lid up and back to allow the roof to enter/exit the boot. Mercedes fluid for the roof pump is expensive and if there was a cheaper alternative available from BMW that would be great news; but I am not sure we are talking about the same pump/manufacturer. s55amg
08-21-2020, 11:42 AM
