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Hmmmmmm ..... I looked every which way, and that really doesn't seem to be possible on my particular year and model, but I have so much work to do under there that (at least) dropping and (likely) removing the subframe should make everything much easier -- to clean as well as to fix. "Easier" being a relative term, of course. Been quite an odyssey thus far Thanks for your input just the same. Much appreciated,
To echo what DrMatt Said, I have replaced the lines and the pump without needing to remove or touch subframe. I undid the bottom engine mount bolts and use a jack to slightly lift engine on the driver side (approximately 1 inch). This was more than enough to handle everything. Obviously it is easier to get to things once the subframe is move but it is not required.
The banjo bolt is reached with combination of wobbly extensions etc.
To echo what DrMatt Said, I have replaced the lines and the pump without needing to remove or touch subframe. I undid the bottom engine mount bolts and use a jack to slightly lift engine on the driver side (approximately 1 inch). This was more than enough to handle everything. Obviously it is easier to get to things once the subframe is move but it is not required.
The banjo bolt is reached with combination of wobbly extensions etc.
I dropped off my 2002 CL500 at a local shop that specializes in AC today. It was recommended by a local car dealer I know. A few hours later, the mechanic called and said the hose from the AC compressor to the condenser is leaking and needs to be replaced, but they refused to work on it after looking at it. I *might* have to tackle the job myself, but I'm a bit reluctant because I'm not sure if I could drop the front subframe myself.
I have a set of car ramp that I use for changing oil and doing basic repair jobs. I think it gives 1.5' clearance off the ground. Is that enough for dropping the subframe?
There are photos of the subframe removal jobs in this thread, but I'm afraid I don't have all the steps in my head. Could someone please write down the steps for dropping the subframe far enough to change the AC hose line? I really appreciate it.
The first time I replaced a tandem pump on a V12TT, I dropped the subframe, and it was relatively easy. Just remember to loosen the pulley bolts before removing the poly-V belt, and get a small tool to undo the rear Torx bolt (a ¼” socket & wrench is too big).
However, the second time I did it (last month) I also followed Matt’s advice and pushed a long socket extension & UJ past the plastic shield above the diagonal arm mounting. That worked fine once I wrapped the UJ with tape to give it some stability.It’s really not that bad a job.
If you do need to lower (but not remove) the subframe though, this is how you do it:
Jack up front of car fairly high (nothing silly) Support on stands under the forward jack points Remove front wheels and lower covers Undo 6 ABC pipe mountings around sides of subframe Remove one small screw on each side, holding plastic shield to chassis rail Remove two engine mounting bolts (just ahead of steering rack) Support engine sump with large block of wood, wider than sump, but narrower than subframe aperture Jack up engine with trolley jack slightly, enough to de-compress motor mounts Loosen all four subframe bolts Support engine support block with second pair of stands Remove the front subframe bolts and lower the subframe carefully, watching out for these loose ends (see pictures above): The PAS return hose is fastened to the subframe on the left hand side (driver’s perspective). Take care not to strain the hose, and disconnect it if you want to lower the subframe very far. Ditto the two electrical cables that run down the RHS wheel arch and backwards to the PAS valve block, and to the ABC pressure regulator.
Commentary:
If you have an engine crane, you could use that to support the engine while you put stands underneath.
The steering column has a universal joint that conveniently sits on the pivoting axis formed by the loose rear subframe bolts, plus flexible feed and return hoses, so the subframe can be pivoted surprisingly far downwards without removing the steering rack (which is a bit of a pain).
The subframe is light (only 23 lbs) so doesn’t need a jack to support. Quite the opposite in fact – the hubs & brakes are heavy, and the control arms lever the subframe upwards, so you have to lift the hubs to lower the subframe.
Loosening the rear subframe bolts provides AMPLE articulation of the subframe; there’s little risk of straining them. Just make sure they’re loose, but not too loose – you don’t want them coming off because they bear the weight of the steering rack (heavy and fragile).
Refitting is the reverse of removal, and you shouldn’t need to adjust the steering geometry, but check to be sure.
While you’re in there it might be a good idea to replace the turbo diverter valves. It would spoil your day if they failed afterwards.
Regards, Nick
Last edited by Welwynnick; 06-12-2018 at 05:13 AM.
Thank you, Wylwynnick for taking the time writing the steps. I ordered the refrigerant hose and o-rings. While waiting for the parts, I realized that my car is a 2002 CL500 so the steps may be a little different. I remember when talking to one of the mechanics at the AC shop, he mentioned that if it was his car he would try to lift the engine high enough without dropping the subframe. Perhaps, he was thinking about accessing the hose's screw to the accumulator from the front.
Do you think replacing the refrigerant hose is possible by lifting the engine 4-5 inches without dropping the subframe?
I think dropping the subframe is less disruptive than lifting the engine, and I wouldn't try to lift it 4 inches.
I did look into this a while ago. From what I recall on my car, the exhaust would hit the transmission tunnel.
Lifting the engine is risky - I did it a few years ago on another car when changing motor mounts, and I broke the engine oil cooler, despite taking great care. There are so many things to go wrong and it's difficult to be sure you've thought of everything.
If you do need to lower (but not remove) the subframe though, this is how you do it:
Jack up front of car fairly high (nothing silly) Support on stands under the forward jack points Remove front wheels and lower covers Undo 6 ABC pipe mountings around sides of subframe Remove one small screw on each side, holding plastic shield to chassis rail Remove two engine mounting bolts (just ahead of steering rack) Support engine sump with large block of wood, wider than sump, but narrower than subframe aperture Jack up engine with trolley jack slightly, enough to de-compress motor mounts Loosen all four subframe bolts Support engine support block with second pair of stands Remove the front subframe bolts and lower the subframe carefully, watching out for these loose ends (see pictures above): The PAS return hose is fastened to the subframe on the left hand side (driver’s perspective). Take care not to strain the hose, and disconnect it if you want to lower the subframe very far. Ditto the two electrical cables that run down the RHS wheel arch and backwards to the PAS valve block, and to the ABC pressure regulator.
Finally, the part (hose from compressor to condenser) arrived. I'm going to tackle the job in the next day or so. If I drive the car onto a pair of ramp, can I skip steps 1 to 3?
I went under the car today to see if I could tackle the job. I put it on the ramps to see how things look first. Mine is a 2002 CL500, and it appears to be different than Nick's photos above. Anyway, I poked around a bit and found that the banjo cylinder is blocking the refrigerant hose. If I remove the banjo cylinder then I think I can remove the hose.
However, I wonder if it's possible to remove the bolt that holds the cylinder and the bolt that fastens the banjo hose to the back of the compressor without disconnect the hoses to the banjo cylinder, lift it away about an inch or so to access the bolt for the hose.
The hose is bolted to the engine or something in the area for support, but if you loosen it you can move it. I don't remember specifically what it was but the last 500 ABC pump I did, I took the cylinder off first, then the pump, as the new pump doesn't come with that little expansion chamber and I had to transfer it anyway. There isn't a lot of room to access the bolts but you can.
If you open the system, either at the hose, or that cylinder, all the fluid from the reservoir will drain out so you will want to drain it first if you can, and prime it when re-filling and first starting.
I'm glad to report that I successfully replaced the refrigerant hose on my 2002 CL500. It was easier than I originally thought. Thanks, everyone.
Here's a short video of it: https://drive.google.com/open?id=1HP...Y0Ex5WNHZKqbKV
don't forget that every time you drop the sub frame, you must do a front alignment
Fortunately, the step of dropping the subframe does not apply for replacing the refrigerant hose on the 2002 CL500. The only thing I had to do from the bottom was removing the bolt at the rear of the compressor which also fastens the banjo hose. That was accessible without removing anything from the bottom other than the dirt covers. The rest of the job was done from the top.
I have an 01 CL500 & need to replace the subframe itself. I found one off of an 06 CL500. Same thing correct ?
Originally Posted by Welwynnick
There are four large E-torx bolts that hold the sub-frame, mounted in each corner.
The engine mounts are bolted to the sub-frame from below, Each mount has a single, hex-head bolt. They're quite small, only need a 1/2" socket IIRC. These bolts screw into threaded holes in the metal mount frame. There's no nut to spin, as such.
There are three bolts at the top of each mount that secure the engine arms to the mounts. On the BiTurbos, these are obstructed by the turbos, which is why people say remove the engine to change them. Not necessary.
Removing the single engine mount bolts from underneath is trivially easy. They're mounted slightly ahead of the steering rack on the W215 & W220. These are the bolts:
Here, the front of the sub-frame is fully lowered (requires the steering rack to be disconnected, but shows what's possible. Basically you can see the engine block and everything attached to it, like the turbos, the engine mounts, the knock sensors, starter motor, alternator, ABC pump, AC compressor, and the infamous ABC line that goes from the pump to the regulator/accumulator).
Top left, you can see the RHS engine mount. In the middle, you can see two cables dangling down. These run down the wheel arch and connect to the steering rack and the ABC regulator. They're clipped to the side of the sub-frame, and you have to be aware of them when you drop the sub-frame.
The only other thing to be aware of is the PAS return hose that runs down the middle of this picture of the LHS of the engine, as seen from the front. That pipe is clipped to both the chassis and sub-frame, so you need to make sure you don't damage that if you lower the subframe.
It could have been a lot more difficult than that. Build and removal procedures consist of EITHER hoisting the engine and transmission in and out of the engine compartment with the sub-frame in position, OR dropping the engine and transmission together with the sub-frame. There is no provision for a different assemble / dismantle procedure like remove/refit the sub-frame with the engine in situ, so there's every reason to suppose that the sub-frame can only be installed with the engine out of the car.
With the exception of that hose and cable, that's not the case. So as long as you unscrew the ABC pipe mounts that conveniently run around the periphery of the sub-frame (and support the engine, obviously) there's very little reason not to lower the sub-frame. Removing it completely is a different matter, as you have to disconnect the lower suspension arms and steering rack, but then you get everything:
Hi sorry to 're open this thread, I'm needing to drop the subframe to replace the usual abc lines turbo diverter valves etc .
I have followed the steps above and even removed brake calipers discs all lower suspension arms steering knuckles disconnected abc pipe clips so from what I can see there isn't anything preventing the subframe lowering.
When I do try to lower it the front drops about 10mm but the rear of the subframe hardely lowers at all, i feel resistance if I try to pull it down, obvs don't want to break anything but just not sure what else is holding it up? The steering rack is still connected but the above states that the frame should still be able to pivot down even with the rack connected?
Any help would be great thank you, Alex
Hi sorry to 're open this thread, I'm needing to drop the subframe to replace the usual abc lines turbo diverter valves etc .
I have followed the steps above and even removed brake calipers discs all lower suspension arms steering knuckles disconnected abc pipe clips so from what I can see there isn't anything preventing the subframe lowering.
When I do try to lower it the front drops about 10mm but the rear of the subframe hardely lowers at all, i feel resistance if I try to pull it down, obvs don't want to break anything but just not sure what else is holding it up? The steering rack is still connected but the above states that the frame should still be able to pivot down even with the rack connected?
Any help would be great thank you, Alex
Welwynnick is the one who published this first, maybe he knows, I would just inspect, it must come down if you disconnect the steering and pushe it up a bit
Welwynnick is the one who published this first, maybe he knows, I would just inspect, it must come down if you disconnect the steering and pushe it up a bit
Thanks yes I'm going to have another look tomorrow when I get chance the only other thing there is mention of a screw each side that holds plastic shield to the chassis so wonder if could be those, can't be much as there's nothing left attached to sub frame which could stop it from pivoting down from what I can see.
Alex
On both sides, remove the small screws that hold the subframe plastic covers to the bottom of the chassis rails. These are clearly visible in the 2nd and 5th pictures in post #2.
On the left side (driver's view), remove the p-clamp that holds the PAS return hose to the subframe (only really visible when you start to lower the front of the subframe.
On the right side, unclip the PAS and ABC wire looms to the subframe.
Here's the key question - Have you loosened or removed the rear subframe bolts?
You can only drop the whole subframe if you completely disconnect the steering rack (which is worth avoiding IMHO).
If the rack is connected, you MUST keep the rear subframe bolts in place - undo them a few turns, but they must stay in place and hold the rack in position.
Once you do that the subframe should pivot downwards at the front, with the hinge being formed by the two rear subframe bolts.
If the suspension arms are fitted, you have to pull the subframe down quite firmly. If the arms are removed, I think it should drop under it's own weight.
If it doesn't do that, your car may be a different build standard to mine. Try looking sideways right through the car, under the rear of the engine. Where the rear subframe bolts pass through the holes in the subframe, they should form a pivoting axis for the subframe to rotate about. The universal joint on the bottom of the steering column should sit on this axis. That's a pre-requisite for the front of the subframe to drop down with the rack in place. If not, your car is different to mine, and you'll have to disconnect the rack.
Good luck,
Nick
Last edited by Welwynnick; 08-16-2020 at 06:06 AM.
Alex
On both sides, remove the small screws that hold the subframe plastic covers to the bottom of the chassis rails. These are clearly visible in the 2nd and 5th pictures in post #2.
On the left side (driver's view), remove the p-clamp that holds the PAS return hose to the subframe (only really visible when you start to lower the front of the subframe.
On the right side, unclip the PAS and ABC wire looms to the subframe.
Here's the key question - Have you loosened or removed the rear subframe bolts?
You can only drop the whole subframe if you completely disconnect the steering rack (which is worth avoiding IMHO).
If the rack is connected, you MUST keep the rear subframe bolts in place - undo them a few turns, but they must stay in place and hold the rack in position.
Once you do that the subframe should pivot downwards at the front, with the hinge being formed by the two rear subframe bolts.
If the suspension arms are fitted, you have to pull the subframe down quite firmly. If the arms are removed, I think it should drop under it's own weight.
If it doesn't do that, your car may be a different build standard to mine. Try looking sideways right through the car, under the rear of the engine. Where the rear subframe bolts pass through the holes in the subframe, they should form a pivoting axis for the subframe to rotate about. The universal joint on the bottom of the steering column should sit on this axis. That's a pre-requisite for the front of the subframe to drop down with the rack in place. If not, your car is different to mine, and you'll have to disconnect the rack.
Good luck,
Nick
Hello
Thank you all so much for the help and advise I successfully managed to lower it this morning, was the small screws each side that holds the plastic cover to the chassis rails that I think stopped it dropping also I did what you advised Nick and put the steering straight so gave more pivot for the drop. I have managed to replace diverter valves and started replacing front abc hoses , kind of worrying as they were replaced by my local independent garage about 3 years ago. All these new hoses have extra covers on them to help protect them from cooking so caught them just in time.
Only issues after those is I notice the lhs engine mount is completely split so I'm weighing up wether to do it or just let garage do it as I already had bought new mounts just in case.
Just the whole dropping steering rack looks bit too intricate...
I'll carry on doing other repairs see how brave I feel after😁
A word of caution to anyone considering disconnecting the steering rack - do not under any circumstances disconnect the steering column at the spline joint where it goes through the bulkhead (like I did). It's incredibly difficult to get the splined joint back together. You just keep pushing the steering column back inside the cabin and you can't stop that. Instead, disconnect it at the steering rack.
In any case, if you do disconnect it, do not turn the steering wheel more than a few degrees or you will break something expensive.
A word of caution to anyone considering disconnecting the steering rack - do not under any circumstances disconnect the steering column at the spline joint where it goes through the bulkhead (like I did). It's incredibly difficult to get the splined joint back together. You just keep pushing the steering column back inside the cabin and you can't stop that. Instead, disconnect it at the steering rack.
In any case, if you do disconnect it, do not turn the steering wheel more than a few degrees or you will break something expensive.
Nick
Nick - are you referring to clock spring or position sensor breaking?