W126 Thermostat

[h17n dj]

Due to my engine running slightly on the cold side, i have bought a thermostat from ECP and wna have a bash at fitting it. is there anybody that could give me a step by step guide or point me in the direction of a 'how to' as to how to do it? its a 91 500SEL. any specialist tools required?

 

[ianrandom]

They seem to be in two slightly different places potentially.
Be careful about snapping off some of the bolts. Some have long shanks so if they are seized its easy to snap them. I did this so had to go to the garage to get a bolt drilled out.

 

[grober]

http://www.w124performance.com/service/W126/w126CD2/program/Engine/107/M117_56/20-110.pdf

 

[h17n dj]

do i need to drain all of the coolant? can it be put back in or do i need to pt fresh coolant in?

 

[grober]

Really depends on when it was changed last--- should be 50/50 water /antifreeze the antifreeze also has corrosion inhibitors which are depleted over time so if it hasn't been changed for a couple of years??? ---- If it's at the right composition and relatively new ---catch what you drain off in a suitable receptacle and use it it to refill the system. If in doubt renew the coolant. You should be able drain off enough using the drain plug at the base of the radiator [ but don't force it- they have been known to sheer off]

 

[h17n dj]

thanks for that buddy.... i doubt its been changed in a few years if im honest so i will just renew it. i may have a go at it tomorrow i think! im not the best person at these kind of things and my old W202 just used to go to mercedes for everything. ive decided with this to do bits and bobs and have a go lol!

 

[h17n dj]

done it ....!!!!! some of the bolts etc were awkard to get to and that but finally sorted and shes running sweeet. thanks for all ur help guys

 

[ianrandom]

Well done