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questions about my 600sec 1995

5K views 44 replies 12 participants last post by  600SEC95 
#1 ·
1. During winter I like to use my engine heater before starting the engine.
However activating the engine heater automaticly starts the climate control fans to warmup the interior .. and it draws from the battery. Can I disable this?

2. Is there a battery voltage display on my car?

3. Where is the OBD1-2 connector on my car ?

Thanks
 
#2 ·
Hi and welcome!
Answer to question 1...Not sure but, it's either in the owner's manual or someone may chime in to help.
Answer to question 2...No there isn't. Use a voltmeter on the battery while the car is running with all accessories running to get true reading. Youtube has vids to cover if you aren't sure how.
Answer to question 3...your car is OBD-1 so there is a port under the hood in your engine bay that you can plug in a LED scan reader. Search the forum for more info
Let us know how you are coming along and show some pics :D
 
#3 ·
Sean has answered the rest ,here is the 38 pin scan location,under the round plug near the firewall on passenger side .:thumbsup:
 

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#4 · (Edited)
Might as well post this info for you .
Don't know if you know or not but your model gets scanned by counting lights that flash with a obd1 scanning tool , mine is the same but I have found that if you use the scanner in the link below , you get all the codes if any & can erase them , it scans the early w140's pretty good & accurate , I posted some of the scans I did within my threats (camshaft sensor trouble).
Expensive yes but powerful , I borrowed this scanner from my mechanic when ever I need it ,currently i'm testing one of the less expensive once but same brand & model .
I have the AUTEL EU702 scanner that supposed to scan W140's but nothing comes up ,it's a piece of crap ,cant even install the software into the PC to update it .
The scanner needs to have version 19:45 on it ( Benz Sprinter al models ) .:thumbsup:

Launch X431 IV Master Auto Scanner Obdii 2 Diagnostic Tool Better Than Diagun 3 | eBay

Testing this one when it arrives with special adapter .
Launch X431 Creader VIII CRP129 Obdii Code Reader Four Systems Diagnostic Tool | eBay
 
#5 ·
#7 ·
I found some broken items while doing some maintenance on my 600SEC .
The cover over the charchoal filter has a drain tube that is broken.. Is that tube supposed to go somewhere or just point outward like that?

I also found a crack in the hydraulic oil reservoir on the rubber piece, is there a replacement available somewhere?

Also those fan assembly screws looks messy..
Will go to the hardware store tomorrow!

Thanks
 

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#13 ·
That drain hose goes into the drain plug at the firewall just behind it , it's a combination ,you see the hole there . If it doesn't fit properly what happens is the water just goes all over the place there .:thumbsup:
 
#8 ·
Hi , can someone tell me what the M120 engine without distributors have in place of them? I have circled a photo of my engine bay.. to the left there is something with two connectors , on the right it's just empty?

The car also now have a new NRF radiator which was cheap, I recommend it! Near perfect fit and no leakages as of 3 days driving around.
 

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#14 ·
Merc-S600 said:
That drain hose goes into the drain plug at the firewall just behind it , it's a combination ,you see the hole there . If it doesn't fit properly what happens is the water just goes all over the place there .:thumbsup:
One more thing I have to fix then. It looks short, must have been cut off at some point.

NZJay said:
Nothing sits in them, they are remnants of the past tech.
Yes if you look on the photo (or your own engine) , the left side have something in it with two connectors.. the right side is empty.
 
#18 ·
1) Unless you put some kind of switch?

2) Yes, put the climate control in test mode, and one of the values will be battery voltage, but you can see the reading of all the temperature sensors..

http://www.benzworld.org/forums/w140-s-class/1691993-need-help-decoding-climate-control-data.html

3) I would not refer to it as OBD 1 or 2 as it was not Mercedes idea to do that, but it is for Mercedes Star which for our cars is HHT is what reads the codes.. Now, on the old cars may have a push-button switch with a LED, and their are plenty of YouTube examples on how to do that, and K6JRF site has some info on it... The correct way of doing it is to use one of these:

http://www.benzworld.org/forums/r129-sl-class/2315329-got-my-mb-star-c4-diagnostic.html

The unit on post 14 works very well too..

All the best,

Martin
 
#19 ·
I was pleasantly surprised that my transmission oil is not cooled inside my radiator , but in an external oil cooler! No risk of mixing fluids if the radiator fails!
I'm thinking about replacing my clutch fan with an electric one . I dislike the clutch fan.. you have no working space and it seems inefficient.
When I park the car on warm summer days, the engine bay is sometimes extremely hot, an electric fan would stay on a while even after the engine is off.
My search has not found anyone else doing this on the M120 engine.. I wonder why?
 
#20 · (Edited)
There was a company in Vermont or New Hampshire (USA), v12s.com, that used to make the shroud and the temperature control board for an electric fan conversion. Not just for Benz, BMW, Jaguar, etc. They are now defunct.

Going all electric will require some serious rewiring and the installation of additional sensors/relays.
Two pusher fans + two more electric fans, running even at 50% speed will be quite a draw.

My $0.02.

Steve

PS You live in the Scandinavia, your summers are not as hot as they are down here.

PPS BTW, change your car description, please. 600SEC is the name used only for the 1993 model year. After that, sedan and coupe were both called S600, until 1997 when the coupe become CL600. Seeing 600SEC with a references to your car always confuses me. You have MY '96 electrics, is your tranny 722.6?
 
#23 ·
600SEC,
Yes please change to S-600. I have a '97 CL600 and you are right. The engine gets really hot as there is no place for air circulation. The engine fills up the compartment. However, I live in the desert where it gets to 49C during the Summer and we have four months of this heat. I drive all over town in this heat but when I get home, I open the hood and let the heat bleed off. I've been through 5 Benzes in 16 years here and have never had a problem with the standard clutch fan except on an early 190. I wouldn't worry about it for the few days it gets hot in your latitude.
Anziani
 
#27 ·
As mentioned I replaced my old radiator with a new NRF radiator. It was probably not necessary but I learned a lot from it. Here is the old Behr radiator as a reference. (notice the lack of transmission coolerline fittings).

Btw .. is the hoodlatch cable supposed to clip into the top of the radiator?
 

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#29 ·
Updates on my car. the NRF radiator is still working fine! It was around 175 USD. Mercedes dealer wanted around 870 USD plus tax for an original radiator ..
Although the temperature gauge is visibly increasing when I rev the engine to speed up on the highway, I guess this must be the waterpump that doesn't keep up?

Obviously the hoodlatch cable goes in the clamps on top of the radiator.. but that doesn't look neat so I routed the cable on the condensor instead. Just want it to look nice and original.
 
#30 ·
Here is a quick fix update that other coupe owners may benefit from.
My dome/courtesy lights did not turn on when opening the doors.. sometimes my seatbelt extender-arms went crazy while driving.
The fix was to replace the door jamb switches!
Not only did it fix two but three problems , my seats automaticly moves forward when tilting the backrest again.. which stopped working 1½ year ago.
 
#33 ·
Have anyone had the need to replace the timing chain tensioner on the M120 engine?
It seems easy to do without tearing down the whole engine.
The reason for asking is a very slight tapping sound can be heard when idling and the fan turned off.. it is tapping faster with increased rpm..
 
#34 ·
Could be valve train noise or an exhaust leak

A mechanics stethoscope goes along way in this situation to pin point the noise. A long screw driver can work also

Is the oil level ok? When was it lasted changed and what grade? Is it louder when starting from cold?

Removing the tensioner requires the RH airbox, secondary air pump and viscous fan\radiator to be removed.
 
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