PeachParts Mercedes-Benz Forum - View Single Post

davidschaffer · #4 01-26-2013, 09:12 PM

Quote:

Originally Posted by Zacharias

A few things:

1. Posting where you are and how cold it actually is, wouldn't hurt, in evaluating no-start problems (some areas are experiencing extreme temps). Also it would be helpful to know if the car starts okay down to a certain temperature.

2. You say the relay "looks okay". Is the glow light coming on on the dashboard? How many glow cycles do you do, before you try to start it?

3. I am guessing you didn't change the rearmost glowplug, as it is the most difficult. That alone should not produce a no-start problem.

4. Have the valves been adjusted recently? Correct valve adjustment is critical on these cars, for cold weather starts.

5. When you plug in the block heater, you should be able to hear a sizzling or crackling sound with 10 seconds as it starts to work. If you can't hear that, the heater probably needs to be replaced.

6. What oil is in the crankcase? If you are in an area experiencing severe cold, synthetic oil allows the motor to turn over much faster.

I am in Northwest Michigan. It has been pretty cold lately ( 0 - 30ish ) but the symptoms started last winter and have gotten worse. I replaced all the glow plugs this fall ( with the exception of the rear most

) In the summer the starts were just okay and the car would vibrate a lot at idle. Before I changed the glowplugs, I did notice that the light was acting strange, sometimes on, sometimes no. Since I changed them, I comes on every cycle, for about 8 seconds. I picked up the car last year on trade and haven't had much time to get to know her. With 225000 and no known history, I would bet the valves need to be adjusted. I will listen for the crackle of the heater or maybe just feel the block when I go out next to try and start it. I have been using a 15/40 oil ( same as my truck ) either valvoline or rotella.

Quote:

Originally Posted by kerry

Have you checked out the glow plug electrics? Are the plugs getting 12 volts with the key in the glow position? Yes, one bad plug can stop the engine from starting in cold weather.

Not yet, I will put a meter to it asap. Why would one glow plug keep it from starting?

You can check the function of the block heater with a non-contact thermometer. You should be able to detect a warm block compared to the surrounding metal. Also, the temperature gauge should show warmth if the block heater has been on for more than a couple of hourse when you turn the key on.

Thanks for the help. I got the car at 212000 last year and picked up a doner that I have used only for the alternator and calipers so far, I think

. I love the car. I drove it down state for thanksgiving and got about 25mpg while doing 80ish. It has it quirks, but I just need to spend more time learning about it. I will post back after some more tests.