w124 e220 Viscous copling removal

[MBK]

guys i'm a bit stuck.

I had a go at removing the viscous coupling on my e220 W124 before i got started i downloaded a really good how to guide with pictures and everything well i got as far as removing the shroud and then got stuck the how to said something about removing a hex bolt from the front of the viscous coupling whilst locking the water pump pulley in place with a 5mm allen key. well my problem is there is no hex bolt on the front of my viscous coupling instead there is a plate with what looks like a pin in the middle. How woul di take this coupling off?? do i need to undo the nut behind the coupling??

any info would be much appreciated.

Also i might change the water pump while i'm at it, i've been told its sumple enough to do.

Thanks in advance

Kully

 

[grober]

No don't touch the plate with the pin its a bimetal strip which controls the viscous coupling. The fan plus viscous coupling is held on to the water pump by the large nut between the coupling and the fan pulley. Its a 36 mm LEFTHAND THREAD nut which screws on to a threaded boss on the water pump. You will need a special water pump spanner - Halfords have them and some way to stop the water pump pulley from rotating. You can achieve this in a crude fashion using a vice grips on the pulley or make up a special tool like mercedes use from mild steel plate.

 

[MBK]

Cheers Graeme,

i have a 36mm Spanner would that work? also im heading down to Euro car parts and i'm going to try find a locking tool for the pulley.

Kully

 

[grober]

Cheers Graeme,

i have a 36mm Spanner would that work? also im heading down to Euro car parts and i'm going to try find a locking tool for the pulley.

Kully

Should work OK if its not too thick. Doubt if ECP will have a locking tool. The special tool mercedes use is very expensive for just one job. Its easy to make one up with 1/8 steel plate and a drill + jig saw. make up a template from cardboard first and then scribe the dimensions on the plate:bannana:

 

[MBK]

are those the tools you used on your car?? if so could you please send me the measurements for the locking tool?? Please.

Kully

 

[grober]

I had a quick look for the tool dimensions but can't lay my hands of them at the moment. will continue to look. The HAYNES manual on the C class suggests an alternative tool which is easier to make perhaps-- details here. I would suggest the w202 C class manual is a valuable read if you intend to do any engine work since it covers your engine. http://www.haynes.co.uk/webapp/wcs/...ctId=13007&langId=-1&parent_category_rn=10215

 

[MBK]

Cheers Graeme thats ACE thank you so much i will fabricate this tool 2mrw i was thinking along the ways of a tool,l like this i've got one for an Astra may see if that fits

Thank you

Kully

 

[MBK]

Hey all done,

Swapped the Viscous fan today, used an oil filter chain around the bolts on the pulley to stop that from moving then used a 36mm spanner to open the nut attached to the viscous fan. overall everything went well i made sure not to put too much pressure on the pulley but all looks ok. Viscous coupling working again.

-Kully

 

[grober]

Well done. Good use of an improvised tool. May help others in the future. :bannana: Secret is not to torque up the nut too tight for next time ---- 40Nm/30 lbf ft recommended.

 

[MBK]

i really need to invest in a torque wrench, but how would i get it to work for a spanner? i just tightened it to how tight it was when i removed it.