Guy's,
Noticed tonight and come to think of it over the past month or so the temp never gets up to the 80 mark when the car is being driven, in fact tonight it was around the 60 mark most of the time. It only reached the 80 mark climbing up hill.
Is this a sign that the thermostat is on its way out? If so how easy is it to change on the ML 270 CDi engine?
Any job sheets on how to change?
Its always been bang on the 80 mark for the past 2 years and only climbs over this when towing the trailer up hills.
Any thoughts appreciated.
I had the same slow warm up 0n my 2001 c270 CDI & it sometimes wouldnt reach 80c unless driven hard for over 10 miles. I changed the thermostat & renewed coolant(as it was due a change) and it warms up quicker now. I also flushed the rad,engine block & heater with pleanty of running water from a hose.
I got my stat from MB deelers as it comes with the stat fixed into the housing & a rubber housing seal (approx £30.)
I would say its easy to renew all i did was-
1. Drain coolant from radiator drain plug(located n/s of car) Best done when engine cold.
2. Undo 3 thermostat housing bolts. You will need a "e" type socket as the bolts have star type shaped heads.(get from any good motorist shop). Not sure on ML,but i had to remove the fuel sensor located in end of fuel rail, to gain access to one of the thermostat housing bolts. Its easy to remove ,but you need a large open end spanner,cant remember size but its around 26 to 28mm. I used a large adjustable spanner. If you need to do this obtain a new fuel sensor seal from a MB deeler
3. If you have a hose,give rad,engine & heater box a flush. Undo one of the heater hoses from the engine bay bulkhead,especialy usefull if engine done high miles & coolant change been neglected.
4. Re connect rad drain plug & any other hoses you disconnect, refit new thermostat(with new rubber seal) Be carefull not to overtighten the housing bolts.
5. On dashboard,put heater temp controlls to max
6. Refill with new coolant/water mixture. 50% ratio is recommended. whilst refilling squeeze rad top hose as this will get rid of any trapped air.
7. When full leave expansion tank cap off,start engine,leave ideling for 10 mins whilst accasionly squeezing top rad hose.Replace expansion tank cap & let engine warm up to max temp (80 to 90c). Stop engine & let cool down for about 3 hours then check coolant level when cold.
Hope this info helps.
There is a Haynes manual for my c270 CDI but not sure if one available for your ML 270 CDI.
