Water pump replacement on 2003 CLK 320
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Water pump replacement on 2003 CLK 320
I'm just about to replace the water pump. Are there any pit falls or difficulties I'm likely to encounter such as air locks etc when putting her back together. All and any guidance will be greatly appreciated. Regards
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W209 CLK 240
I need to replace the pump on my CLK 240 so watching this thread with interest.
I've watched roughly a million YT how to videos on the M112 water pump and it does look fairly straightforward. Major concerns seem to be making a note of which bolt goes back where and the risk of shearing the bolts when removing the pump.
I've watched roughly a million YT how to videos on the M112 water pump and it does look fairly straightforward. Major concerns seem to be making a note of which bolt goes back where and the risk of shearing the bolts when removing the pump.
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I'm working on her now when I'm done I'll tell you everything I've learnt. It's 7pm now and about to start the disassembly. Probably finish the installation and testing tomorrow. If you can wait that long 😂
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For rich 1068 Progress on my CLK 320 water pump replacement
Hi rich 1068
I tried to attach photos to help you but was unsuccessful. This is not a complicated job but it's very time consuming. However let's try and give pointers.
1. Can I suggest you check out a post /!thread from SwissKiss on 08.21.2019 at 11:57 am, it was most helpful.
2. It's not a complicated job but it's back breaking and time consuming.
3. Preparation was everything in this job, get everything you need before starting.
4 The absolutely most important item is that making of a cardboard cut out of the pump with holes to place each bolt removed in its correct place on the pump out line. I can't stress the importance of this enough,it's a life saver. Thankfully I took notice of SwissKiss's advice.
5. Use a tube to direct coolant from the radiator drain point ,as it comes out from the side of the valve
6. Wasn't prepared to strip all the shielding to gain access to the drain plug on the driver side of the engine block. So she held approximately 3 litres of old coolant. Takes 10 litres in total.
7. You can't rush the removal and reinstallation,so give yourself plenty of time.
8. Mine had the paper gasket, you'll have one or the other , someone mentioned using both , I would strongly advise against this.
8. To assist with positioning the new gasket I used a silicone RTV instant gasket lightly applied to both surfaces.
9. I tried a number of ways to align the pump back , with various combinations of bolts in place , all were hopeless. Just do your best to keep the gasket in place and offer the pump into position with no bolts . Then use the first small bolt to align the first gasket hole ,then go to the opposite end of the pump and do the same , slowly working your way round the pump until all are back in place.
10. As you offer up the pump into position , firstly slide the small oil cooling hose into place, then start positioning the bolts. Have this hose connected at the pump end and not the other way round.
11. Watch out for these
a . Remove the electrical connector located just above the top of the pump , to give clearance because the pump slips in behind it.
b. On reassembly be careful not to pinch the wiring harness that runs by the Alternator to the top of the engine.
c. There's an installation/ fixings plate with two bolt that go into the top of the pump. When you remove them this plate can fall down slightly and then you can't see one of the bolt fixings, and if like me you'll wonder why the pump isn't coming loose.
11. Check that your alternator bolt slides easily through the steel bush sleeve location hole in the new pump . Mine didn't, and only when I'd painstaking got it all back together did I find this problem, that required removal to drill a clearance hole. That was a really really painful thing to be forced to do. Mine was an After Market Pump absolutely identical in every way apart from that one hole diameter.
12. Remember your thread sealant, do each one as you replace as it can get messy .
Good luck , and hope this helps just a bit
Regards Nissrolet
I tried to attach photos to help you but was unsuccessful. This is not a complicated job but it's very time consuming. However let's try and give pointers.
1. Can I suggest you check out a post /!thread from SwissKiss on 08.21.2019 at 11:57 am, it was most helpful.
2. It's not a complicated job but it's back breaking and time consuming.
3. Preparation was everything in this job, get everything you need before starting.
4 The absolutely most important item is that making of a cardboard cut out of the pump with holes to place each bolt removed in its correct place on the pump out line. I can't stress the importance of this enough,it's a life saver. Thankfully I took notice of SwissKiss's advice.
5. Use a tube to direct coolant from the radiator drain point ,as it comes out from the side of the valve
6. Wasn't prepared to strip all the shielding to gain access to the drain plug on the driver side of the engine block. So she held approximately 3 litres of old coolant. Takes 10 litres in total.
7. You can't rush the removal and reinstallation,so give yourself plenty of time.
8. Mine had the paper gasket, you'll have one or the other , someone mentioned using both , I would strongly advise against this.
8. To assist with positioning the new gasket I used a silicone RTV instant gasket lightly applied to both surfaces.
9. I tried a number of ways to align the pump back , with various combinations of bolts in place , all were hopeless. Just do your best to keep the gasket in place and offer the pump into position with no bolts . Then use the first small bolt to align the first gasket hole ,then go to the opposite end of the pump and do the same , slowly working your way round the pump until all are back in place.
10. As you offer up the pump into position , firstly slide the small oil cooling hose into place, then start positioning the bolts. Have this hose connected at the pump end and not the other way round.
11. Watch out for these
a . Remove the electrical connector located just above the top of the pump , to give clearance because the pump slips in behind it.
b. On reassembly be careful not to pinch the wiring harness that runs by the Alternator to the top of the engine.
c. There's an installation/ fixings plate with two bolt that go into the top of the pump. When you remove them this plate can fall down slightly and then you can't see one of the bolt fixings, and if like me you'll wonder why the pump isn't coming loose.
11. Check that your alternator bolt slides easily through the steel bush sleeve location hole in the new pump . Mine didn't, and only when I'd painstaking got it all back together did I find this problem, that required removal to drill a clearance hole. That was a really really painful thing to be forced to do. Mine was an After Market Pump absolutely identical in every way apart from that one hole diameter.
12. Remember your thread sealant, do each one as you replace as it can get messy .
Good luck , and hope this helps just a bit
Regards Nissrolet
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W209 CLK 240
Excellent post @Nissrolet And I'll seek out that @SwissKiss post.
Now, off to buy some brave tablets....
Now, off to buy some brave tablets....
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Posts: 22
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Honestly brave tables not required, a back support / brace would be useful though because you'll be bent over for hours in the most uncomfortable of positions 😂. I wish I could work out how to send you the pics that would have given some additional confidence. Using the attachment paperclip didn't work for me. Remember to buy sufficient coolant additive 5 litres of concentrate.
