andrewcliffe
Active Member
Changed my radiator today. Fairly straightforward for the DIY mechanic, although time consuming. This is based upon my 1999 C43 AMG, but I guess much will be relevant to other W202's. I have some pictures which I'll be adding in due course.
Some of this will require access from underneath. If you are fortunate to have access to either a 4 post lift or a pit, then you’re lucky – otherwise its axle stands I'm afraid. Take proper precautions when working underneath a car - someone I know was working underneath their car supported on a jack only and the car fell off. They suffered 200 fractures and took 18 months to recover (and he considers himself lucky)
You need to budget quite a bit of time to this – MB quote 3 hours but if you are not working at MB mechanic speeds, allow 5 or so. Helper not required although handy.
Special tools are required. Can be sourced locally, or even made, or you could hire mine from me.
1 Open bonnet to the vertical position
2 Remove top engine cover (clips)
3 Remove engine undertray (4 screws, 8mm socket, 2 clips) (from underneath)
4 Drain coolant (remove header tank cap), coolant drain point under LH side, use wide screwdriver and have something to drain into. (underneath)
5 Using special tool to hold viscous fan still, use other tool to undo nut holding viscous fan to its carrier (conventional RH thread). Carefully lower fan to ground and store vertically. (mostly from above)
6 Remove fan shroud – 2 clips at top, two pegs at bottom and manoeuvre out from underneath. (underneath). Remove two radiator U shaped clips from above at same time.
7 Remove front should – 2 plastic clips at top, lift off at bottom. Note how bottom clips over flange. Use Philips screwdriver for top clips, or narrow plain screwdriver (from above)
8 Undo radiator upper cross member – two bolts either side, and one in middle on front edge. 10mm socket (above)
9 Prise out 3 clips which hold the air intake pipes in place. A Y shaped tool is quite good for this. They're fragile. Carefully manoeuvre out. Tricky requires manipulation. (above) I found the RH one (LH as you look in the car) to come out easier forwards, and the other one to come out into the engine bay.
10 Undo two bolts holding a/c condenser to radiator. 10mm socket (above)
11 Undo 4 hoses. Two on RH side, require 7mm socket, one on LH side, plus small one from header tank at top LH corner (requires pair of pliers) (above/underneath)
12 Radiator should now be free and should lift up and out. (above)
13 Lift out captive nuts where a/c condenser bolts to (magnet useful) and swap over rubber trim along top edge (above)
14 Re-assembly is the reverse of this step by step. When reattaching viscous fan, the torque is 45Nm. As the special tool you use may not have a torque wrench attachment, one way is to hold a torque wrench in a bench vice set to the required level, and holding it at the same length as the special tool, to assess what 45Nm feels like.
15 Refill. Total capacity is 9 litres (C43), of which between 4 and 5 litres should be antifreeze. I put a couple of litres of water in, checking for leaks, then the antifreeze, then topped up with water. Run car until hot. Heat should come out from heater vents, if not there is an airlock. I didn’t have such a problem. After short test drive, top up water. Monitor for a few days with 2l Cola bottles of water in boot (just in case)
16 Dispose of any old coolant / antifreeze in the correct manner.
Some cars may have an additional AFT cooler built into the system which will require ATF joints to be split and immediately plugged. This will require the AFT levels to be checked afterwards, not something easy as Mercedes blank off the dipstick tube and do not provide the owner with a dipstick.
Additional: The radiator I put into my car had additional screw fittings for presumably an ATF cooler. My old radiator didn’t have these and there was a slightly different part number, but other than that, they were identical. As this may have caused a water leak, I made some M14 x 1.5 plugs from a couple of old bolts I found. I shortened them on a lathe to roughly the right length, then using a suitable die & die holder, cut a new thread. Thread was sealed with a copper washer and Wurth pipe lock – an anaerobic liquid seal. I found there was a foul condition between a headlamp mounting bracket and the upper of the two bolts, so the head of one was carefully ground away. Hopefully this should be OK. I would possibly suggest a M14 x 1.5 Core plug, or sawing off the head of the bolt and possibly cutting in a slot for a screwdriver.
Tools required:
8mm, 10mm sockets with extensions
Pliers
Drainage tray
Phillips Screwdriver (or narrow plain screwdriver)
Plain screwdriver (wide for drain plug),
7mm socket or plain screwdriver for hoseclips
Pair of Viscous fan tools
pliers for one spring loaded hose clip
Parts required
New radiator
4-5 litres of antifreeze
4-5 litres of water.
Watering can / funnel etc.,
Some of this will require access from underneath. If you are fortunate to have access to either a 4 post lift or a pit, then you’re lucky – otherwise its axle stands I'm afraid. Take proper precautions when working underneath a car - someone I know was working underneath their car supported on a jack only and the car fell off. They suffered 200 fractures and took 18 months to recover (and he considers himself lucky)
You need to budget quite a bit of time to this – MB quote 3 hours but if you are not working at MB mechanic speeds, allow 5 or so. Helper not required although handy.
Special tools are required. Can be sourced locally, or even made, or you could hire mine from me.
1 Open bonnet to the vertical position
2 Remove top engine cover (clips)
3 Remove engine undertray (4 screws, 8mm socket, 2 clips) (from underneath)
4 Drain coolant (remove header tank cap), coolant drain point under LH side, use wide screwdriver and have something to drain into. (underneath)
5 Using special tool to hold viscous fan still, use other tool to undo nut holding viscous fan to its carrier (conventional RH thread). Carefully lower fan to ground and store vertically. (mostly from above)
6 Remove fan shroud – 2 clips at top, two pegs at bottom and manoeuvre out from underneath. (underneath). Remove two radiator U shaped clips from above at same time.
7 Remove front should – 2 plastic clips at top, lift off at bottom. Note how bottom clips over flange. Use Philips screwdriver for top clips, or narrow plain screwdriver (from above)
8 Undo radiator upper cross member – two bolts either side, and one in middle on front edge. 10mm socket (above)
9 Prise out 3 clips which hold the air intake pipes in place. A Y shaped tool is quite good for this. They're fragile. Carefully manoeuvre out. Tricky requires manipulation. (above) I found the RH one (LH as you look in the car) to come out easier forwards, and the other one to come out into the engine bay.
10 Undo two bolts holding a/c condenser to radiator. 10mm socket (above)
11 Undo 4 hoses. Two on RH side, require 7mm socket, one on LH side, plus small one from header tank at top LH corner (requires pair of pliers) (above/underneath)
12 Radiator should now be free and should lift up and out. (above)
13 Lift out captive nuts where a/c condenser bolts to (magnet useful) and swap over rubber trim along top edge (above)
14 Re-assembly is the reverse of this step by step. When reattaching viscous fan, the torque is 45Nm. As the special tool you use may not have a torque wrench attachment, one way is to hold a torque wrench in a bench vice set to the required level, and holding it at the same length as the special tool, to assess what 45Nm feels like.
15 Refill. Total capacity is 9 litres (C43), of which between 4 and 5 litres should be antifreeze. I put a couple of litres of water in, checking for leaks, then the antifreeze, then topped up with water. Run car until hot. Heat should come out from heater vents, if not there is an airlock. I didn’t have such a problem. After short test drive, top up water. Monitor for a few days with 2l Cola bottles of water in boot (just in case)
16 Dispose of any old coolant / antifreeze in the correct manner.
Some cars may have an additional AFT cooler built into the system which will require ATF joints to be split and immediately plugged. This will require the AFT levels to be checked afterwards, not something easy as Mercedes blank off the dipstick tube and do not provide the owner with a dipstick.
Additional: The radiator I put into my car had additional screw fittings for presumably an ATF cooler. My old radiator didn’t have these and there was a slightly different part number, but other than that, they were identical. As this may have caused a water leak, I made some M14 x 1.5 plugs from a couple of old bolts I found. I shortened them on a lathe to roughly the right length, then using a suitable die & die holder, cut a new thread. Thread was sealed with a copper washer and Wurth pipe lock – an anaerobic liquid seal. I found there was a foul condition between a headlamp mounting bracket and the upper of the two bolts, so the head of one was carefully ground away. Hopefully this should be OK. I would possibly suggest a M14 x 1.5 Core plug, or sawing off the head of the bolt and possibly cutting in a slot for a screwdriver.
Tools required:
8mm, 10mm sockets with extensions
Pliers
Drainage tray
Phillips Screwdriver (or narrow plain screwdriver)
Plain screwdriver (wide for drain plug),
7mm socket or plain screwdriver for hoseclips
Pair of Viscous fan tools
pliers for one spring loaded hose clip
Parts required
New radiator
4-5 litres of antifreeze
4-5 litres of water.
Watering can / funnel etc.,
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