Jun 10, 2015, 12:43 PM
Last edit by: IB Advertising
See related guides and technical advice from our community experts:
Browse all: Cooling System Guides
- Mercedes-Benz C-Class: How to Replace Thermostat
Step by step instructions for do-it-yourself repairs
Browse all: Cooling System Guides
DIY: Thermostat Replacement for 2003 1.8l C230 Sport Sedan | W203
Thread Starter
Newbie
Joined: Jun 2007
Posts: 12
Likes: 1
From: Round Rock, TX
C230K Sport Sedan '03
DIY: Thermostat Replacement for 2003 1.8l C230 Sport Sedan | W203
Hi All,
OK, I finished my Thermostat DIY and PDF. I have to give props to both forum contributors here and to the staff at www.Mymercedesparts.com. They were very helpful in getting me the right parts and encouragement to work on my car.
Appreciate your feedback on the PDF. Also, going to work on a DIY and PDF for Oil change next.
Mods, please let me know if the PDF is OK, and please place this on the DIY page.
Enjoy!
OK, I finished my Thermostat DIY and PDF. I have to give props to both forum contributors here and to the staff at www.Mymercedesparts.com. They were very helpful in getting me the right parts and encouragement to work on my car.
Appreciate your feedback on the PDF. Also, going to work on a DIY and PDF for Oil change next.
Mods, please let me know if the PDF is OK, and please place this on the DIY page.
Enjoy!
Last edited by edawg; Jan 7, 2011 at 12:36 AM.
Newbie
Joined: Dec 2005
Posts: 11
Likes: 0
edawg,
Thanks for all the hard work, I know it takes a while to put something like that together. And thanks to making a specific DIY for C230's in response to the C280 thread I saw you in. Just in time for me too
And I backup your MyMercedesParts.com suggestion, I checked 6 different online parts stores and it was the cheapest, although some others were only a few bucks more.
I have a question: Do we have to drain the coolant at all? Did you include this just in case we wanted to change coolant while we were there? I imagine that if I don't drain the coolant, a little coolant might spill from the top/front of the engine block, but not a whole lot. And whatever spills can be replaced. Is this true?
Thanks
Thanks for all the hard work, I know it takes a while to put something like that together. And thanks to making a specific DIY for C230's in response to the C280 thread I saw you in. Just in time for me too
And I backup your MyMercedesParts.com suggestion, I checked 6 different online parts stores and it was the cheapest, although some others were only a few bucks more.
I have a question: Do we have to drain the coolant at all? Did you include this just in case we wanted to change coolant while we were there? I imagine that if I don't drain the coolant, a little coolant might spill from the top/front of the engine block, but not a whole lot. And whatever spills can be replaced. Is this true?
Thanks
Thread Starter
Newbie
Joined: Jun 2007
Posts: 12
Likes: 1
From: Round Rock, TX
C230K Sport Sedan '03
I have a question: Do we have to drain the coolant at all? Did you include this just in case we wanted to change coolant while we were there? I imagine that if I don't drain the coolant, a little coolant might spill from the top/front of the engine block, but not a whole lot. And whatever spills can be replaced. Is this true?
Thanks
. My concern with not doing this - your car's coolant probably has not been changed in many miles. I recommend you do this to be on the safe side. I live in Austin, TX, where we have 6-8 months of warm months throughout the year. Above 80F!
So, if you are going to go through the trouble of changing the T-Stat, might as well change the coolant. Plus it will save you the $100+ a stealership will charge you!
At any rate, it's your choice
. Thanks for the kinds words.
Junior Member
Joined: May 2010
Posts: 59
Likes: 0
cclass
THANKS!!!!! I just finished changing mine. Your pics and instructions are perfect!
As seenastyle stated not much coolant will come out so draining the coolant is not necessary. I did mine this way plus I did NOT take the hose off the housing. I did try but it was on there pretty good then I realised it did not need to come off.
I might have lost a cup of coolant and that is all. I think the trick is to jack the front end of the car up so it's on an angle. This way not much coolant will "spill" out of the engine. I did mine on my driveway which has a slight incline. Had I had thought it through, I would've jacked it up instead to get a greater angle but like I said I didn't lose much coolant anyway.
Thanks again EDAWG for the writeup!
As seenastyle stated not much coolant will come out so draining the coolant is not necessary. I did mine this way plus I did NOT take the hose off the housing. I did try but it was on there pretty good then I realised it did not need to come off.
I might have lost a cup of coolant and that is all. I think the trick is to jack the front end of the car up so it's on an angle. This way not much coolant will "spill" out of the engine. I did mine on my driveway which has a slight incline. Had I had thought it through, I would've jacked it up instead to get a greater angle but like I said I didn't lose much coolant anyway.
Thanks again EDAWG for the writeup!
Junior Member
Joined: Jan 2011
Posts: 35
Likes: 0
C230 2003
I just changed my thermostat today due to getting the code for it. I bought the thermostat and o-ring for 37 euros here in Germany. I used this DIY except for I didn't change the fluid and I didn't disconnect the hose from the thermostat housing. Also, I jacked up the front end and I believe this helped to prevent losing alot of fluid. It took me about three minutes to do the thermostat swapover. I couldn't believe it was that easy to be honest. Thanks for the DIY.
Henry
Henry
Trending Topics
Member
Joined: Feb 2010
Posts: 86
Likes: 5
From: San Francisco
2005 E320 Base
MB World Stories
The Best of Mercedes & AMG
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun
Verdad Gallardo
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Verdad Gallardo
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine
Verdad Gallardo
Flawlessly Restored Mercedes 190E Evo II Heads to Auction
Verdad Gallardo
Electric Mercedes C-Class Unveiled: 11 Things You Need to Know
Verdad Gallardo
Mercedes EQS Gets A Major Update: Everything You Need to Know
Verdad Gallardo
5 Underrated Mercedes-Benz Models That Don't Get the Love They Deserve
Verdad Gallardo
Mercedes 300D Has Pushed Well Past 1 Million Miles and It Ain't Stopping
Verdad Gallardo
10 Most Reliable Mercedes-Benz Models You Can Buy Used
Verdad Gallardo
Member
Joined: May 2011
Posts: 147
Likes: 0
05 C230K Sport
great diy. I did this yesterday and it took me about two hours. if I need to do it again I could probably trim that to an hour. cost me 90 dollars getting parts and coolant from the dealer. could have went online cheaper but I am a live in the moment type guy and wanted to fix it right away. thanks for the write up. saved me alot of money.
MBWorld Fanatic!
Joined: Dec 2006
Posts: 1,105
Likes: 11
From: Toronto, Canada
2019 C300 Wagon; '75 Triumph TR6; previous: 2004 C230 6spd sold after 17 years of driving
Before I had a code reader and Star DVD, I had a check engine light and had to go the dealer to find what was going on, they had to replace my Thermostat and it cost about $200 here in Toronto
Junior Member
Joined: Mar 2012
Posts: 44
Likes: 0
From: Mid-Atlantic, USA
2005 W203 C320
What is the correct ?
Hello; I am in the middle of air intake, cabin, engine flush, filter & oil, P/S flush and refill, fuel filter replacement, anti freeze flush and refill, Accessory belt and thermostat, I had to stop and ask a
question... What is the correct torque for the 2, T10 bolts on the Thermostat housing?
Tomorrow I will be tackling the transmission flush, via the ATF cooler line and TCM plug, is oily from the bottom of the bell housing to the front of the transmission pan., so it was due!
I hope to clean well tonight before I stop and leave it ready for trasmission maintenance service tommorow...
Thanks for you priceless Help!
question... What is the correct torque for the 2, T10 bolts on the Thermostat housing? Tomorrow I will be tackling the transmission flush, via the ATF cooler line and TCM plug, is oily from the bottom of the bell housing to the front of the transmission pan., so it was due!
I hope to clean well tonight before I stop and leave it ready for trasmission maintenance service tommorow...
Thanks for you priceless Help!
Last edited by Allrevup; Nov 17, 2012 at 03:48 AM. Reason: spelling
MBWorld Fanatic!
Joined: Aug 2007
Posts: 1,544
Likes: 87
From: San Jose, CA
2010 c300
edawg thanks for creating the instruction and link to buy the parts. I've been getting this error on and off and it eventually stayed on. So going to be doing the swap over the weekend. Thanks again.
Senior Member
Joined: Jun 2013
Posts: 262
Likes: 34
From: Houston, TX
'05 S430, '05 S600
Thanks for the PDF. I just did this on my car at 144k miles. The twist for me came in the form of a broken thermostat housing. That set me back a little since I was not expecting it. Went to the closest MB dealer and picked up a new one for about $30. Looking back now, I should've expected that since it is a plastic part and with all the temperature cycling it is only a matter of time before it becomes brittle and breaks. Felt like I should write about it here for everyone else to know. Again, thanks a million to this forum!
Member
Joined: Sep 2013
Posts: 139
Likes: 4
From: Finland, Europe
W203 C200CDI
Nice DIY indeed
Just a reminder in case some CDI-engine owners happen to read this, you have a 2nd thermostat fitted in your car which needs to be changed aswell. Price from (finnish) dealer 46e ~ $63
It is located behind the sound horns in front of the radiator grill and changing it is quite easy job when you block hoses with special pliers (unless you flush the coolant out).
Just a reminder in case some CDI-engine owners happen to read this, you have a 2nd thermostat fitted in your car which needs to be changed aswell. Price from (finnish) dealer 46e ~ $63
It is located behind the sound horns in front of the radiator grill and changing it is quite easy job when you block hoses with special pliers (unless you flush the coolant out).
Last edited by cvx; May 10, 2014 at 03:34 AM.
Super Member
Joined: May 2006
Posts: 546
Likes: 10
From: Cumberland, RI U.S.A.
2005 C230WZ SS Capri Blue/Ash
Thanks for the PDF. I just did this on my car at 144k miles. The twist for me came in the form of a broken thermostat housing. That set me back a little since I was not expecting it. Went to the closest MB dealer and picked up a new one for about $30. Looking back now, I should've expected that since it is a plastic part and with all the temperature cycling it is only a matter of time before it becomes brittle and breaks. Felt like I should write about it here for everyone else to know. Again, thanks a million to this forum!
Had the same thing just happen to me on my housing at 119K miles. The crack on the outside of the tube was small, but enough to have a little coolant bubbling out of it. But the inside was pretty bad....the plastic tube that goes into the engine was completely broken off the outer part of the housing. I didn't have to but I ended up replacing the thermostat as well, since I was in there.
Pic 1 - before
Pic 2 - after
--Cintoman
Newbie
Joined: Feb 2020
Posts: 5
Likes: 1
2005 MB C230K
Had the same thing just happen to me on my housing at 119K miles. The crack on the outside of the tube was small, but enough to have a little coolant bubbling out of it. But the inside was pretty bad....the plastic tube that goes into the engine was completely broken off the outer part of the housing. I didn't have to but I ended up replacing the thermostat as well, since I was in there.
Pic 1 - before
Pic 2 - after
--Cintoman
Pic 1 - before
Pic 2 - after
--Cintoman
07, 2003, 2007, 230, c230, change, cost, diy, long, mercedes, mercedesbenz, mercvedes, price, replacement, replacementthermostat, sport, thermostat
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
