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2011 GLK,2007 S550,2003 S55,2008 CLK,2009 C300,1996 E300,2005 E320,2002 E3
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Discussion Starter #1
Fellas:
I took my 129 out for a ride today, and she got hotter than the Sun. She was almost redlining. The guy that I purchased the car from a few weeks ago is a MB mechanic, and had at least 20 various MB's on the lot ranging from W140s, W124's, etc. The car was a customers car. He told me that the car needed a radiator which I expected to have to buy. The oil looked good(not changed), and the antifreeze looked clean as well. I figured it would be an interesting project after driving my brothers car. .................HERE is the kicker. it was warm today in Cleveland, so after driving for 10 miles and the car got very hot, I assumed that the radiator was clogged and restricting flow causing the temp to rise. I got off early this afternoon, so I popped the hood. Something told me to check the thermostat>>>
WOW i lifted the housing and only the top part of the thermostat was there. Now the question for the experts is---what could someone have done this for? It was actually only a piece of the themostat. What could that have hidden? Im sure there is no way the car could have been driven over 10 miles without getting hot. needless to say, I grabbed a thermostat this pm and put it in. I havent driven the car after reinstalling the new thermostat, but my mind has been drifting to the worst scenerio. I hate even thinking those 2 words...H*** Gas***, so i wont even type them...SMH
 

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87' 190E 16V / 93' 600SL / 02' G500
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Easy way to check for H*** Gas*** problems is buy a kit that checks for CO (exhaust gas) in the expansion tank. Most people figure if the car is overheating a good way to cure it is to pull the T-Stat.... But in reading your post you did mention the guy you purchased the car from was a MB mechanic and if he didn't check these items before selling the car he may want to "step awayyy from the tools" or you should run.... Replace the thermostat and take the radiator out, have the radiator checked now that you've been in the coolant. Did you hear the fan clutch lock or the electric fans kick in?
 

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2011 GLK,2007 S550,2003 S55,2008 CLK,2009 C300,1996 E300,2005 E320,2002 E3
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Discussion Starter #3
Mike:
Now that you mention it, I didnt hear the fans kick on. I remember many moons ago pulling a thermostat to keep a car from overheating, which is what surprised me when I saw this one was literally gone. Because he seemed trust worthy, I assumed the radiator was bad, though it wasn't leaking. When I pulled the thermostat housing, I was blown away with possible scenarios as to why it was gone.
 

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2015 Jaguar XF R Sport Twin Turbo, 1992 500sl Pano, 1999 CBR 1100XX, Super BlackBird, Jaguar X Type
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I believe these engines are the same as 928 Porche i.e. silicone impregnated bores with no liners it's a great design but the one thing it will not tolerate is overheating. This may cause major problems so try and solve it before you start running it hot (if not too late). Removal of the stat would have been done in the effort to make it run cooler.
I think I would check for coolant loss first and if so look for the leak, hoses, radiator, rad cap etc. Radiator pressure check next and make sure the water pump is working properly and hoses are not collapsing with age.
I'm sure there will be more opinions & advice given from more knowledgeable members, but good luck with the fix.
 

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'93 SL500 (sold), '88 GMC Sierra 360,000 miles, '86 Yamaha FJ1200 (criminally fast)
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I didn't read about any coolant spraying, leaking, or steam. I didn't read about a coolant FOG coming out of your exhaust pipe ( H/G), & blocking the view of the 20 cars behind you.

I can only guess.... radiator.
 

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87' 190E 16V / 93' 600SL / 02' G500
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If compression is getting into the cooling system you wont get the cloud of doom just lots of heat and a expansion tank cap that's working overtime to release pressure. Good to hear you didn't hear the fans as you probably have a chance at it just being the fans or defective fan switch. Just thinking if the mechanic suspected radiator not a bad time to pull the radiator and have the flow rate checked. Wouldn't hurt in the long run. Not sure how to bridge the fan switch at this point to check that at least your electric fans work. currently with my 600 fans have not come on but I have heard the clutch fan lock. Going to be checking my fan switch as well very shortly. My clutch fan kicks on at 100 degrees celsius if that helps and if someone knows how to bridge or manually turn on the electric fans please let me know. I have the repair CD coming but has yet to arrive.
 

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Water in the oil? Oil in the water? Too much continual pressure or foaming on the radiator? Steam from the exhaust? Constant water loss? Compression low or lowering from one end of the head to the other?

Any of these can be signs of a bad head gasket but a bad head gasket may just be seen in one or more symptoms, usually not all of them.
If the thermostat was rigged so that there is more flow or that it never shuts then yes it was done so it stays cooler. I cant picture your description. Im also wondering if you mean there is the "plate" part from a broken thermostat just sitting there that would restrict the water flow?
 

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1995 Mercedes SL 320
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Fans

I successfully installed individual fans switches on our 95 SL320. The fans quit working on their own and was causing the engine to overheat in traffic. I pulled the power off of one of the metal fuse links up by the windsheild. They work great as long as you remember to turn them on......lol. In the summer I usually had to run both in the city with stop and go traffic, but would shut one down on the highway. I installed them under the steering wheel. Hope that helps. BTW I used the two wire connection by the headlight area to connect the wires.
 

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1994 SL500
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If the coolant was not low the head gaskets are probably ok. Head gasket leaks generally blow the coolant out of the radiator, not 100% certain but good odds. The fan relay is in the box behind the underhood fuse box by the LH hood hinge. If you follow the wiring from the fans back you should find a connector behind the left headlight. With a couple of jumpers power one side and ground the other. If the fans run take it out for a drive and watch the temperature, if it stays in the normal range you have found your problem. From personal experience I can tell you that if the fans quit running it will heat up in 90+ degree weather particurlarly with high humidity, I am assuming that Clevland is humid. Los Angeles is not and the engine fan will not carry the cooling alone here when we get into the 90's. FYI the cylinders are indeed unlined high silicone aluminum, they will take a lot of punishmet but will not tolerate overheat or lack of lubrication. With regards to the thermostat I have seen thermostats blow apart from overheat, the thermostat may well be a result of and not a cause of the overheat. The "pill" that controls the thermostat is a piston and cylinder full of a liquid with a high expansion rate, the hotter you get it the more it wants to expand, so it could have expanded enough to blow the lower half of the thermostat off. The question now is where is the lower half and is it in a water passage causing a restriction? Since the coolant flow is from the bottom to the top the tendency would be to wash the parts up and not suck them down. Hopefully it is in the water passage just below the thermostat somewhere. With a flashlight and small mirror you should be able to see most of that passage, best to find the parts if you can. Good luck in your quest.
 

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'93 SL500 (sold), '88 GMC Sierra 360,000 miles, '86 Yamaha FJ1200 (criminally fast)
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Somewhere in here.... ( Clinton?) ... Showed an adapter that plugs between the harness wiring to the fans, that will turn on the fans at a lower temp, lowering the coolant by 10 degrees? ( it is a clean little adapter)
 

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Mike:
Now that you mention it, I didnt hear the fans kick on. I remember many moons ago pulling a thermostat to keep a car from overheating, which is what surprised me when I saw this one was literally gone. Because he seemed trust worthy, I assumed the radiator was bad, though it wasn't leaking. When I pulled the thermostat housing, I was blown away with possible scenarios as to why it was gone.
Here's a simple way of checking if you've any water in the oil. Get yourself an aluminium bottle top or similar. Pull the dipstick out and get a few drops of your oil off the dipstick into the bottle top. Even better try to get a length of thin plastic pipe down the dipstick hole, to the bottom of the sump (that's where the water will be) and get a sample. About a spoonfull should do. Using a cigarette lighter or similar gently heat up the bottle top from underneath. Probably a good idea to a) wear gloves b) move away from the car. If the oil merely smokes or bursts into flame that's good. If it crackles and spits and gives off steam that's bad. Not highly scientific I know, but quick and simple.
Regards
Steve
 

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1999 SL500, 2004 CLK500, 2006 Cadillac SRX
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I believe these engines are the same as 928 Porche i.e. silicone impregnated bores with no liners it's a great design but the one thing it will not tolerate is overheating. This may cause major problems so try and solve it before you start running it hot (if not too late). Removal of the stat would have been done in the effort to make it run cooler.
I think I would check for coolant loss first and if so look for the leak, hoses, radiator, rad cap etc. Radiator pressure check next and make sure the water pump is working properly and hoses are not collapsing with age.
I'm sure there will be more opinions & advice given from more knowledgeable members, but good luck with the fix.
Poundy, I think you are close - what I always heard was that the Porsche 928 engine was made by Mercedes in the 560 era, as in 5.6 liter engines from the 80's.
 

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^^^When it was running...
Well, okay, there was a time when the the drive shaft splines became corrupted and the engine would turn but the wheels would not. I sold it to a buddy who invested the money to get it in order. He had a good time with it, too. AC was weak.
 

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72 280SE 88 560SEC 92 E500 6.0 95 SL320 14 GLK350
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Well, okay, there was a time when the the drive shaft splines became corrupted and the engine would turn but the wheels would not. I sold it to a buddy who invested the money to get it in order. He had a good time with it, too. AC was weak.
Come on now, let it out; tell us about the overheating problems and electric glitches.
 

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1999 SL500, 2004 CLK500, 2006 Cadillac SRX
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Overheat - no, electrical - yes. But, after visiting the dealer and going to spend $1400 (in 1986) to replace the mother fuse board, but they not having one in stock, I went home, took it out, VU metered every connection (IT WAS POINT TO POINT HARD WIRED) - all checked out. I used contact cleaner and wire brushed every fuse connection - everything that wasn't working - worked!!
 
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