SL/R230: Roof opens/closes very slowly after hours of inactivity but gets faster afterwards
Thread Starter
Junior Member
Joined: Oct 2015
Posts: 27
Likes: 0
From: Taipei, Taiwan
Camry 2.0, CLK320, SL350, SL63
Roof opens/closes very slowly after hours of inactivity but gets faster afterwards
Hi guys, my car’s roof is acting weird. It opens / closes very slowly if the vario roof has not been operated for like 4~5 hours. A youtube vid recording my roof closing is here:
As you can see, it almost hung in the half way of the operation. Trunk lid also moved very slowly.
But, the weird part just began…
After ONE slow opening or closing operation, subsequent operations become smoother and faster. That is, my roof will open / close a lot faster and smoother after one or two abnormal operations.
Other notes:
- All my hydraulic cylinders had been rebuilt last year. Mechanics have confirmed that all struts, hoses and junctions are properly sealed and not leaking. In fact, the fluid level in the pump reservoir remains the same over past few months.
- My hydraulic pump had just been rebuilt last month. The problem existed before pump rebuilt so this problem shouldn’t be caused by bad installation. In fact we rebuilt the pump because it was deemed to be the cause of this problem. But now seems like it’s not the case.
- It is checked that no air bubble is inside the hydraulic system.
- Slow operations took about 35 secs as shown in the vid. Subsequent faster operations took about 20 secs. Faster and significantly smoother but still not as fast as a normal operation (16 secs).
- If a roof operation is NOT performed for next 4~5 hours, whether the car is running or not the roof resumes back to “slow mode”.
I once thought that there is some kind of pressure accumulating mechanism and mine failed. But mechanics said there’s no such thing.
Anyone has similar experience? Any feedback is greatly appreciated.
As you can see, it almost hung in the half way of the operation. Trunk lid also moved very slowly.
But, the weird part just began…
After ONE slow opening or closing operation, subsequent operations become smoother and faster. That is, my roof will open / close a lot faster and smoother after one or two abnormal operations.
Other notes:
- All my hydraulic cylinders had been rebuilt last year. Mechanics have confirmed that all struts, hoses and junctions are properly sealed and not leaking. In fact, the fluid level in the pump reservoir remains the same over past few months.
- My hydraulic pump had just been rebuilt last month. The problem existed before pump rebuilt so this problem shouldn’t be caused by bad installation. In fact we rebuilt the pump because it was deemed to be the cause of this problem. But now seems like it’s not the case.
- It is checked that no air bubble is inside the hydraulic system.
- Slow operations took about 35 secs as shown in the vid. Subsequent faster operations took about 20 secs. Faster and significantly smoother but still not as fast as a normal operation (16 secs).
- If a roof operation is NOT performed for next 4~5 hours, whether the car is running or not the roof resumes back to “slow mode”.
I once thought that there is some kind of pressure accumulating mechanism and mine failed. But mechanics said there’s no such thing.
Anyone has similar experience? Any feedback is greatly appreciated.
Last edited by a32amg; Dec 12, 2018 at 05:25 AM. Reason: video link update
MBWorld Fanatic!
Joined: Mar 2018
Posts: 1,442
Likes: 260
From: Netherlands
2005 R 230 SL350 (M112 3.7). Sold the 1966 W113 230SL recently
I am VERY interested in opinions about this, having a similar problem (suddenly slow roof). Takes about 35 secs in all. Until that is fixed I’ll keep the foam padding from the pump because the pump gets very hot quickly. So I’d like to suggest to keep that in mind during prolonged operation as described.
Banned
Joined: Jan 2006
Posts: 1,982
Likes: 393
From: Atlanta, unfortunately
'09 S600, (2) R129 300SLs, '03 SL500, '03 SL55
When I bought my '03 car in July, 2006 the roof operated as yours does now. Half a dozen or so years later it got much, much worse so that it took c. 90 seconds to complete an open or close operation. A thorough diagnosis which included hydraulic pressure measurement revealed nothing wrong. Then a couple of years ago for no apparent reason the roof started functioning in a properly-quick manner, and it's been perfectly fine ever since.
Having a SmartTOP module which obviates the need for holding the roof control switch and also allows the top to operate while the vehicle is in motion made having a slow roof tolerable to me.
Having a SmartTOP module which obviates the need for holding the roof control switch and also allows the top to operate while the vehicle is in motion made having a slow roof tolerable to me.
Trending Topics
Banned
Joined: Jan 2006
Posts: 1,982
Likes: 393
From: Atlanta, unfortunately
'09 S600, (2) R129 300SLs, '03 SL500, '03 SL55
The pump has overload protection implemented as an electronic thermocouple which signals the roof ECU the temperature of the pump motor. On another SL I have seen where this minder intervened and interrupted roof operation to allow the pump to cool. That happened after 2-3 minutes of continuous operation.
MB World Stories
The Best of Mercedes & AMG
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun
Verdad Gallardo
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Verdad Gallardo
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine
Verdad Gallardo
Flawlessly Restored Mercedes 190E Evo II Heads to Auction
Verdad Gallardo
Electric Mercedes C-Class Unveiled: 11 Things You Need to Know
Verdad Gallardo
Mercedes EQS Gets A Major Update: Everything You Need to Know
Verdad Gallardo
5 Underrated Mercedes-Benz Models That Don't Get the Love They Deserve
Verdad Gallardo
Mercedes 300D Has Pushed Well Past 1 Million Miles and It Ain't Stopping
Verdad Gallardo
10 Most Reliable Mercedes-Benz Models You Can Buy Used
Verdad Gallardo
MBWorld Fanatic!
Joined: Mar 2018
Posts: 1,442
Likes: 260
From: Netherlands
2005 R 230 SL350 (M112 3.7). Sold the 1966 W113 230SL recently
Senior Member
Joined: Feb 2018
Posts: 258
Likes: 34
From: Gluckstadt, MS
2003 R230
I am having a slooooow roof too. When I closed it several hours later it stopped without the trunk closing. Went inside to get help and was able to get it to close with slight pressure assist from my hand. Pump is full and no apparent leaks. I don’t have the equipment to check the line pressure but do have Isoft mb tool.
Junior Member
Joined: May 2021
Posts: 18
Likes: 2
From: Tucson, AZ
2004 sl55, 2005 GX470, 2004 XJ8
Possible cause of slow vario roof opening
Hello
Have you checked your struts? I found out there are 4 gas struts that carry the weight of the roof components. Hydraulics were designed assuming the 4 struts hadn't worn out. The ones on my 2004 SL55 had worn out, and from the articles, worn-out struts put added pressure on the hydraulics to compensate.
There are a few good threads on finding and replacing the struts. I just did 3 of 4.
Have you checked your struts? I found out there are 4 gas struts that carry the weight of the roof components. Hydraulics were designed assuming the 4 struts hadn't worn out. The ones on my 2004 SL55 had worn out, and from the articles, worn-out struts put added pressure on the hydraulics to compensate.
There are a few good threads on finding and replacing the struts. I just did 3 of 4.
MBWorld Fanatic!
Joined: Mar 2018
Posts: 1,442
Likes: 260
From: Netherlands
2005 R 230 SL350 (M112 3.7). Sold the 1966 W113 230SL recently
I found out there are 4 gas struts that carry the weight of the roof components. Hydraulics were designed assuming the 4 struts hadn't worn out. The ones on my 2004 SL55 had worn out, and from the articles, worn-out struts put added pressure on the hydraulics to compensate.
There are a few good threads on finding and replacing the struts. I just did 3 of 4.
There are a few good threads on finding and replacing the struts. I just did 3 of 4.
