My baby don't start like she used to! - PeachParts Mercedes-Benz Forum

abracadabra · #1 10-20-2009, 05:19 PM

Okay, I've had my '76 W115 240D for 6 years now, starting has always been a breeze. Hold the gorilla knob for a little until the salt shaker glows, then start, no gas pedal just starts right up. This was how things were even through last winter where here in Portland we had some of colder temps I've experienced in the NW, in the 20's.

All I ever did was change oil and filters, have the valves adjusted once a year.

Then through this summer it got harder to start, especially on cooler mornings, until a few weeks back when things got in to the 40's I needed to give it gas to start, until finally I couldn't get it started cold at all! When it warmed up, fine, it started, so I suspected glow plugs, which I've never changed out. And the salt shaker wasn't lighting up either.

So I changed out the plugs with new Bosch fast glows, which were what was in there to begin with. Now, wow, the salt shaker glows again, and the car starts.....BUT: I still have to give it gas to start, and it always stalls out a time or two before it idles roughly until warm. When its warm it starts, but not instantly like it used to.

So I haven't had the valves adjusted in awhile, so I'll start there. But the car runs well once its started.

Here's other info:

-my highway fuel mileage dropped from a dead even 30 which I got for years to about 27 on my last trip in the spring to Montana
-looks like one of the injectors at least is leaking, its not the return lines I suspected them first and replaced them all
-the injectors nail when its cold, but don't when the engine is warmed
-I have no idea how stretched the timing chain is
-I never had the compression checked because the car always started right up in the cold weather, the compression at least has to be decent
-I do go through some oil but I suspect most of this is through some minor leaks. There is exhaust smoke but its not blue its grey and smells like diesel.
I guess I'm just looking for other suspects, I'm at a point where the car needs a good deal of front end work (tie rods etc) and I'm not sure if its gonna be worth all the money to get it back in to shape, at least if the starting issue points to something more major....

Any pointers would be great!

mark in Portland

jimishadow · #2 10-20-2009, 05:33 PM

how many miles since valve adjust?

abracadabra · #3 10-20-2009, 05:37 PM

I think I'm pretty close to 10k since last valve adjust.....

mark

pawoSD · #4 10-20-2009, 05:44 PM

Have you ever replaced the injector nozzles or had them tested/balanced?

abracadabra · #5 10-20-2009, 05:46 PM

Never had the injectors out, nozzles replaced, tested, nothing. Never had a reason to, until now maybe?

In most of the reading I've done it seems 10K isn't too long for valve adjustments, and I last had mine done by the people who do all the work I don't want to do, and they do a great job. So...I have a gut feeling its not the valves. Now, the injectors, well.......??

mark

79Mercy · #6 10-20-2009, 06:01 PM

Can you tell a difference in how fast your starter spins the motor?

abracadabra · #7 10-20-2009, 06:44 PM

I haven't noticed the starter spinning slower except when I couldn't get the engine started before the glow plug change....then it turned slower as the battery wore down. But it did start after I changed the glow plugs even without recharging the battery!

mark

brownrice78 · #8 10-20-2009, 07:17 PM

Do the W115s' have an idle knob?? I think maybe you need to look into that if you need to give it some gas in order for it to maintain idle when the engine is cold. My 83' 240D would sometimes shut off without a bit of gas when first started. I adjusted the idle knob and then could turn the knob to the left when the car is cold and it would run great. When warm, I could turn the knob to the right and run normally.

Skippy · #9 10-20-2009, 07:29 PM

I vote for injectors.

kerry · #10 10-20-2009, 07:57 PM

Recheck your glow plugs. Have you checked to make sure all of them are getting 12 volts? My recollection is that you have jumper wires from plug to plug. So if the wire from plug 2 to 3 is not making good contact, plug 4 wont work either since you are relying on the jumper wires. If two are not heating up, it would account for a rough idle and slower starting.

abracadabra · #11 10-20-2009, 09:42 PM

First thing I did after I put the new glow plugs in and it still didn't start like it should (although like I said the salt shaker glowed for the first time in months) was to check voltage at each plug, getting 12V at all 4.

Gonna look in to the injectors.......methinks it could be the issue....

mark

79Mercy · #12 10-20-2009, 09:45 PM

Why don't you do a compression test before you pay to have the injectors tested.

Harbor Frieght sells a tester for 25 bucks.

#13 10-20-2009, 11:35 PM

Quote:

Originally Posted by Skippy

I vote for injectors.

That seems like a good possibility. I just had my injectors replaced after some hard starting and nailing. Two of them were pretty bad and the other three had marginal spray patterns. The valves "shouldn't" be the problem if they were adjusted 10k miles ago.

katchung · #14 10-21-2009, 12:39 AM

Quote:

Originally Posted by Craig

That seems like a good possibility. I just had my injectors replaced after some hard starting and nailing. Two of them were pretty bad and the other three had marginal spray patterns. The valves "shouldn't" be the problem if they were adjusted 10k miles ago.

I'm no expert, but I'd check the glow plugs again and then pull the injectors, do a compression test and check the health of your engine...and when you see how bad your nozzles look you will want to clean them or likely do a rebuild. I'm guessing they are clogged if you have never serviced them...have you noticed a reduction in power when the starting issues began?