a challenge for veterans....where to start? - Page 2 - PeachParts Mercedes-Benz Forum

dunl · #16 07-30-2006, 07:02 PM

Okay, thanks for pushing me on checking the plugs. Just for all the newbies in the future looking at this thread:

I WAS AN IDIOT, AND WAS GOING TO PURCHASE NEW GLOW PLUGS JUST IN CASE, INSTEAD OF CHECKING THEM ALL FIRST. DUMB, DUMB, DUMB ME, BECAUSE I JUST CHECKED THEM ALL AND THEY WERE FINE, AND I WOULD HAVE BLOWN ABOUT $15 EACH ON NEW ONES. LUCKILY, I CHECKED ON HOW TO TEST THEM WITH A METER AND THEY ARE FINE. DON'T BE SCHTOOPID LIKE I ALMOST WAS.

Okay, hope that was kinda clear for anyone contemplating the same mistake I almost made.

Only problem is that the battery died, and didn't have enough charge for me to tell if the loose wire I found on one of the glow plugs (#1 or #5 - closest to the rad?) was the actual problem. I could actually see it pop out of the space it was in when it heated enough to expand it a little.

One problem solved - time to charge a battery.

jrgslg · #17 07-30-2006, 07:05 PM

Cool,moving in the right direction

P.E.Haiges · #18 07-30-2006, 07:30 PM

dunl,

I thought U said the "W" wires between the GP were hot. That would mean the GP are working.

If it still won't start after U are sure the GP are working, try a push start. It is easy if its a manual transmission, harder on an automatic because U have to go faster. Do U have any big hills near U?

P E H

dunl · #19 07-30-2006, 07:45 PM

First I went out with a multi meter and tested the plugs...all seemed fine. I noticed yesterday there seemed to be some bare bit of warmth coming from them, but wasn't sure if they were all working or not (not that I realize they are in a series, of course they should have been working, if warmth was actually what I was feeling).

Same thing today, until I touched one and realized they are hot enough to sear skin on contact.

Why would I touch it? Well, just by chance I turned the key and immediately looked into the engine bay, only to see the one wire pop out one heated and expanded by the current. Soon as I touched it there was a spark.

One slightly seared fingertip - but I know it works.

It's an automatic, but I already know that it will "tow start", as the previous owner stated he did that, according to the directions in the manual for doing so. No big hills nearby, but I guess if I did get it running, I could do the milli volt method, right?

P.E.Haiges · #20 07-30-2006, 08:05 PM

dunl,

If U got it running by pushing it, U could see how it runs. If it was timed too early it would knock, timed late is harder to determine but it would cause a loss in power but U don't have a baseline to compare it to.

Also if U got it running, you could get it hot and see if it starts with the starter. If it starts hot and not cold, it could be a compression loss problem.

I had a 220D that way, wouldn't start cold, but would start hot. Had to use a tank type heater to get it started cold, even on warm days. If electric wasn't available, I had to park it on a hill and roll start it. Once started, it ran very well. What happened to it to cause the low compression was the rings loss their temper from overheating because it was run dry.

P E H

dunl · #21 07-31-2006, 12:36 AM

Okay, let's say that I get it tow-started tomorrow. What is a list of things I will want to do, look out for, watch, and check while it is running.

i.e. What should my procedure for tomorrow be all together, including tow-starting it (I'm in the Prairies, few hills.

)

t walgamuth · #22 07-31-2006, 06:48 AM

yeah, and you can use spray lubricant to start and run it with a second person spraying into the intake while you crank. not thru the air filter though. this will start one if fuel is the issue. or if priming is needed.

i would think this will also start a diesel with the injection timing wrong.

tom w

coldwar · #23 07-31-2006, 10:04 AM

Quote:

Originally Posted by dunl

So where could I get new glow plugs here in Canada for a 300d?

I'm in Canada and my indie mechanic ordered them in and had them same day. I would think any place that deals with Bosch could get them- including Canadian Tire. I see you've already discovered your old series-plugs really are working, and I agree you still need to get her running. But I definately recommend converting to the 12V pencil plugs, whether it's with the full conversion kit including relay, or doing it with a push-button the way I did- definately makes for easier starting no matter what. With the old series- type plugs, you're actually losing heat energy outside the engine through those nichrome wires (the W shaped ones that get hot). With parallel 12V plugs, all the heat goes where it's needed and your glow interval is reduced from 60 seconds to 15 or less, and the start-ups are more certain also.

Dave
1976 300D

barry123400 · #24 07-31-2006, 10:32 AM

You have found a marginal connection in your series glow plug set up. Repair it and with a charged battery it will now hopefully start. If so turned out pretty simple and not really suprising. Assume for now the past owner got the drip test right. But you might also ask him if he had to move the pump very much to get it. If he did you might want to check for excessive chain stretch. If it runs I personally would still check the valve clearances unless the previous owner verifies they were done in the last 25.000 miles. Without the aid of excellent sites like this some previous owners might assume the engine had hydralic lifters for example. Or just have never bothered. Yet many complaints can result from them being way off. These items are also part of a general tune up for maximum power, milage, and starting ability. I always do this before putting any old 123 diesel aquisition into general use as even if nothing is found it is time well spent. Lots of hints in the archives about cleaning ground connections etc. as well. Just improves reliability in general.

dunl · #25 07-31-2006, 01:43 PM

I remember him saying something about checking the chain and it didn't show excessive stretch.

So if I spray some WD40 down the intake tube while starting, long as there is fuel it should start?

Lostyankee · #26 07-31-2006, 02:27 PM

Lets review.
You believe the pervious owner (also called @!.$%@$~!#) may have tinkered with the injection pump timing? What leads you to think this?

To perform the voltage reading on the glow plugs to time the IP, you have to have the engine running!

I'd try to get her started and then go on to other issues. In other words get a base mark or starting point. Prove what works and then tackle some of the nasty stuff.
I assume you are as green as I was with my 1st MB diesel.
1. Buy a small CO2 fire ext. to squirt in the intake incase you have a runaway diesel. Review runnaway posts.
2. Charge the battery.
3. Press the STOP lever on the valve cover linkage and make sure it moves.
4. Crack the injector to nozzle nuts 1/2 turn. Turn the engine over BUT DO NOT LET IT RUN. After a few revs. you should see (while in the driver's seat) #1 cyl. area getting wet from fuel.
5. When all IP to nozzle line nuts are wet with fuel, tighten the nuts, clean up the mess and try to start the beast.
6. If the beast does not start: Pull the valve cover and inspect the timing chain. Look at other posts for TC info.

Now you know you have fuel getting to the nozzles, fuel system is working, there is a timing chain and if a runnaway, you can shut the engine off. You did have ear plugs handy didn't you?
Now check the marks on the timing chain gears to make sure the chain did not jump a tooth. If chain and gears are OK, look into the IP.
Many MBs are $ pits because clogged fuel strainers and the owner changed parts starting at the wrong end of the system!
So prove what works (yes, try the radio first!) and then go on from there. While your tinkering, try everything electric to start your list of window regulators & their sliders, blower motor, whiper motor, horn ... saves shipping $ and keeps your from the dreaded AFBP (Another F!@#$ Bad Part) syndrom.
From what I've read I would not attempt timing the IP. I'd take it to a shop that has done many, many, many of your exact IP and motor. This is not a Goooomer Pyle garage job.
Good luck and post your results.

dunl · #27 07-31-2006, 05:04 PM

Okay, recent update:

1. Battery recharged. Tried spraying the wd40 down intake pipe, no worky. Did however see some small tufts of smoke coming out intake pipe from wd40 getting hot, I presume.

2. Looked in the engine a little closer and noticed it seemed pretty cramped down by the small fuel filter compared to my 80 300sd. Looked closer, and there was a rubber line that I don't have on mine. Looked really close....4ft of fuel line from the metal fuel line to the filter, all coiled up. Fuel filter straight up in the air, 50% at the top was air.

3. Cut line excess off (anyone need any line, I have about 3.8ft of it left....), bled the fuel lines out, and decided to try starting again. No go.

4. Tow start....nothing. Maybe I needed to get faster, but we were goin 35kmph with it when I tried to start it.....nothing.

Didn't crack the injector to nozzle nuts....we'll try that after the next battery charge.

P.E.Haiges · #28 07-31-2006, 08:39 PM

dunl,

Better to push start than pull start. If something happens, you are not tethered to the tow vehicle. If the engine starts and gives a quick burst of power, U don't run into the back of the tow vehicle.

35 MPH may not be fast enough with an auto transmission. What gear did U have the shift lever in? 60 MPH may not be too fast. Did the engine rotate when U were towing it? U can tell by looking at the oil pressure gage. If it goes full scale, the engine is rotating.

If it won't start by a fast enough push start, its not getting fuel or something is seriously wrong with the engine.

P E H

dunl · #29 07-31-2006, 08:44 PM

Well, a push start is out of the question, as I live in the flats (prairies).

As for the oil guage, I never noticed, as I was too busy trying not to run into the tow vehicle.

I had it in neutral, then low as suggested by the manual.

How bad of an indication is it if it wouldn't give a good healthy cough with WD40 sprayed down the intake?

And we just researched and found out that the diesel in it is probably 2 years old....I assume it wouldn't be any good, then?

bgkast · #30 07-31-2006, 08:51 PM

Try checking the cam chain streach using the quick "tower" method. That will tell you if the cam is way off. Are you sure that your glow plugs are working? Sounds like your "find" is an older sister to mine.