Not starting ... 87 300D ... :(
 

I know we have enough of these threads, so I apologize for starting another one. I've done a lot of searches and reading, and talked to my indy this morning. Just curious what you guys think. The car started fine most of the winter. During a bad cold snap in early Feb., it would not start, just cranked. GPs check out OK. The battery in it was very old, so I bought a new one from Autozone. Before I had a chance to put the new one in, the temps went up, car started, so I left the new battery in the back of my other car to put in later. About a week ago, the 300D wouldn't start again (it was about 25-30 degrees out), so three days ago I muscled the new battery in, started it up, A-OK. The next morning when I cold started it, it started but whew did it kick and bang around for about 10 seconds, then smoothed out. The next day, yesterday, it had even more trouble, even though it was about 40 degrees out. Once it had started, it was easy to start again immediately, but after sitting for about five hours was again a little rough on startup. This morning I checked the GPs cold, and sure enough 1 and 3 are bad. Then I tried to start it ... no go ... it's 55 degrees out! It seemed to me, and my indy agreed, that two bad plugs should not cause the car not to start when it is this warm out. He gave me some starter fluid and said to use a very little bit tomorrow to get the car started and bring it over to him. I'm sure he'll figure it out for me, but just out of curiousity, do you guys think it could be a battery issue? I just wonder because I did put the new battery in so recently ... and the new battery had sat in the back of the other car outside for a couple weeks, so many that had an effect on it? Or do you think it's just the GPs?

One other thing ... car is low on fuel ... not down to reserve yet, but low. Could it be a fuel delivery issue? I know if that's the case it might become more problematic the lower the fuel level gets. Just wondering.

... just thought I'd add, for complaining's sake, that I think my cars are conspiring against me. For the third time this winter, the Jeep has thrown up a warning light shortly after the MB developed a problem. It's not a big deal, I can still drive the Jeep (well, this time at least), but I just found it amusing. I should stop parking them next to each other ... I think they plan this $&%*.

How are the filters?

Bad GP's also give this sort of initial running qualities. Use wd-40 instead of the ether. It's not as addictive.

BTW, I love your drawing of your car. Can you draw a w123?

Maybe you've got a bad GP relay. Mine is bad, but not so bad that's it's causing starting problems. If a relay goes bad though, there's really no telling how it could malfunction. It could not turn off power to the GPs when it's supposed (causing premature GP failure) or have a short causing a greater draw than normal leading to symptoms that would make you think your battery is bad (this is the problem I am having).

I think your next step after replacing the bad GPs (if they are indeed bad) is to get your hands on a GP relay that is known to be working and swap it out.

justin - I did a voltage check on the six pins at the relay box with the key turned on ... got 12v at each pin ... wouldn't that suggest the relay is OK, or is there more to it than that? Also tested the strap fuse and that was OK.

rrgrassi - my primary filter looks dirty ... I was just going to change it today, but put off the project. I don't think it can be anywhere near clogged enough to cause a no-start situation ... the car has been performing great. I had thought tank strainer, too, but it seems to me the car would be performing not-so-well in that scenario? :confused:

... Glad you like my drawing ... thanks! I'll bet I could draw a 123 ... been a while since I've picked up a pencil, but I doubt I've lost anything. :P Only thing that could be hard would be if it were a dark-colored car ... the "shine" is very tough to do with colored pencils, moreso on a dark color. But, I'd be willing to try.

I believe there is more to it than that. In both of the possible "bad relay" cases I mentioned above, you would be getting 12V at the pins as expected I believe.

I'm pretty sure my GP relay is bad because my battery is good and my GPs are good, but this is what happens for me:

1) Attach multimeter to battery so that you can watch the multimeter while turning the key on/off.
2) Get in the car and turn the key on to light the GPs, note the voltage drop and watch for a trickle of voltage back up.
3) With the key still in the on position, watch the multimeter and let the 30 seconds pass so you can hear your GP relay clicking off and also note the increase in voltage at the battery when this happens.
4) Turn the key off and then back on again, does the same voltage drop occur this time as noted in Step 2?

For me, it's not the same (Step 4) and I want to get my hands on a good GP relay so I can at least prove or disprove this belief.

The answer to the first question depends on your starting technique. If you usually glow the system until the light goes out and then turn the key to "start", the procedure works fine in warmer weather and the engine will fire right off with six working plugs.

But, if you expect the 603 to fire right off using this technique with two bad glow plugs, it gets a bit dicey. It might go if the compression is very good...........it might not. Furthermore, it's possible that you've got more than two bad plugs.

If you wish to circumvent this issue, temporarily, glow the plugs for 35 seconds until the relay shuts down.............then immediately turn the key to start (NO DELAY). It should light off with a full glow cycle on four.

In any case..........DO NOT...........use ether on the 603. If you make a mistake on the amount, you risk serious damage to this engine. Far better to call a tow truck...........just isn't worth the risk.

With regard to low fuel, it's highly unlikely that this will prevent a start. However, I have noticed that the '86 will definitely lose power as the tank gets very close to empty. I'll bet it loses some fuel pressure due to a partially clogged strainer. But, you would have noticed this situation prior to this issue..........the vehicle would have felt sluggish when very low on fuel.

Change the filter as well. My car was getting hard to start, and I could not get much help with the hand primer either. Changed primary and secondary filters, and all became good again.

Check all the GP circuit like Justin advised.

My car is supposed to be midnight blue, so I'm saving my pennies to get her repainted to the original color. Right now it's orient red. Nice color also, but I like midnight blue better. So after a repaint, I'll pay you for a drawing of my car. No need to add shine.

Thanks, all, for the advice. I am crossing my fingers it is just some bad plugs. I know for sure the 1 and 3 are bad, and it's certainly possible another one or two are shoddy ... there was another one (can't remember which one) that kind of bobbled between .9 and 1.2 ohms so maybe that was on the outs, too. Of course, I am sitting here at work trying to think of the most horrible possible thing it could be so I can worry myself into a frenzy ... I believe at this point I have "Munchausen syndrome by auto.":dizzy2:

Thanks for the advice on the ether, Brian. It didn't sit well with my. My indy was very adament that I not use too much, to the point that it scared the ^$&% out of me. I know he knows what he's doing, but I think he may have overestimated my ability (or confidence) to use the perfect amount. He knows I'm pretty savvy, so I guess he figured it was OK. But, I think I am going to be a sissy about it (not always a bad thing, right?) and wait until Thursday to start this thing ... it will be only 40 degrees tomorrow and almost 70 Thursday ... no brainer. If it doesn't start then, I'm gonna take your tow-truck advice. My indy is only about 3 blocks from my parking lot, though ... so if anyone has a strong horse and a good harness ... ;)

One more Q: I know these starters can take a good deal of cranking ... but how long do you let it crank before deciding it just ain't gonna happen. I kind of feel like if it's not going after a few seconds, it's not going ... maybe I'm giving up too soon? What's the appropriate count before giving up on that particular go?

Replace those filters,,, my 300SD (617) will not idle if the primary is dirty,,, also makes it tough to start.

I have noticed that the amount of fuel in the tank can make a difference in cold starts. It is a good idea to change your filters, but also try filling doing a few roundtrips to the diesel station in the Jeep and get at least 10 gallons in and see if it makes a difference. On that same note, if your tank is getting low and you park facing uphill you aren't doing yourself any favors.

Ive read that the engine being sluggish when on a low tank is due to a worn out and ready to go lift pump?
My 300D does the same, when nearing low tank it loses some power and idle gets a little rougher. I think it was reid (dieseldiehard) who was telling me it might be a wearing lift pump.

cant remember who told me or where i read it exactly.....

Re: how long to crank.

I am coming from a W123, but I have cranked it for more than 15 seconds before in the cold (on 3 of 4 GP's) and it started.
I am at the point where I can listed to the noise it makes while turning over to see if its worth continuing. Listen to the sound the engine makes if you hit the starter without letting it glow. Then listen to the engine after a good glow time - the engine sounds "smoother" (like the cylinder is firing but not hard enough to push the engine on its own). If starting is questionable, let it turn over for 5 or 10 seconds, see if the noise it makes changes, if not, then give up, it it starts turning over faster/smoother then keep the starter turning.

You 603 starter may not like this (most people with 240D's put 5cyl starters in them anyway...), but there is a sound that it makes.

I thought that Brian Carleton or someone put up instructions on how to start your diesel in cold weather/low battery/bad GP's and it went something like this-
2 glow cycles, (I do 3 if its quesitonable)
leave the starter turning until the battery dies or the engine starts- once you let up that GP heat has more chance to leave the engine where it is needed.

This is just what I've seen, on an older and smaller motor with fewer cylinders.

-John

If I can recall where I placed it, you won't have that issue! :eek:

Tried adding fuel (I added a lot of fuel to the pavement, too ... ugh), no go. I let it crank for a good while, 15 seconds or so, and it just didn't seem to be going anywhere. About 40 degrees today. I am so bummed over this. I will try again tomorrow, when it's going to be 65 degrees out. That might make the difference.

Didn't get a chance to change the fuel filter; might try that tomorrow. Considering the engine is already having a tough time starting, would it make it even harder when it has to prime after I put the new filter on? Only thing that makes a fuel delivery issue seem unlikely is that I have not seen any of the performance or idle problems you guys mention with such issues. Just the no start.

I'll wager a set of Euro lights that it's one of the following:

1) Bad strip fuse in the GP relay.

2) Bad GP relay.

Have you tested for +12v present AT THE GLOW PLUGS while glowing? The car is almost impossible to start without functional GP's. BT, DT, have the t-shirt....

:silly:

Have not tried that ... just tested at the relay pins (got about 12.49 on each). Do you need to pull the GP to get an accurate reading or can you poke the probe in where the wire connects?

No need to pull the plugs - just touch the meter lead to the nut on the end, look for 10-11v.

Also do a GP resistance check with the harness unplugged from the relay. At the plugs you should read 0.6 ohms, or under 1.0 anyway. At the 6-pin connector it may read around 1.0 ohms. Anything higher and you may have bad plugs. What brand are in there, and how old are they? It sounds like you have at least 2 known bad plugs, right? You're going to have to bite the bullet and replace all 6 with Bosch or Beru (avoid Autolite or Monark). The car may not start if you only have 2 or 3 functional plugs.

:(

Replace all the suction side fuel lines -- bet they are cracked and leaking, allowing air in and the fuel to drain back into the tank. Will cause very difficult starting due to fuel starvation.

Replace all six glowplugs, too -- if two have died, the rest are going fast.

Replace fuel filters -- if the pre-filter is cruddy, the main filter is likely plugged or nearly so, it's much finer.

Do not, ever, use ether on an MB diesel unless you want to rebuild the engine, it will almost always fracture the ring lands on the compression ring.

Peter

That was what led me to find the two bad plugs ... both tested infinite on the multimeter (plugs 1 and 3) ... the others all tested around .9, although one kind of waffled between .9 and 1.2. I thought, and my indy agreed, that two bad plugs should not completely stop the car from starting in 50 degrees ... but, I suspect there is more than just the two that are sub par. Or, like you said, it's the relay.

Here's a question: I do not think I can replace the plugs myself (well, I am sure I CAN, but considering my lack of tools and experience and where the car is parked, I think it may not be the time to try), all of them that is. What if I were to replace just the #1? Would that help it start enough to get it to my indy, so he can do the rest? Just an idea. Obviously, some of the plugs are less of a bear than others ... :eek:

Be sure to glow it for the full cycle (approx. 35 seconds) before attempting the start. Crank it for 20 seconds. If it won't go, there are other more complex issues than two bad glow plugs.

If your battery is getting weak, charge it, since the starter needs to spin the engine as fast as possible.

WD-40 is a viable option instead of ether.

Try why Brian says first, after checking for 12v at the plugs. If extended glows still won't let it light, with a fully charged battery, tow it to your indy for six new Bosch/Beru plugs. (Triple-A Plus towing is well worth the annual cost, btw!)

You have checked the 80A strip fuse, right? That can fracture almost invisibly, allowing enough voltage to show +12v at the relay pins with no load, but zero volts under load. This is a very common failure.

:pirate:

Checked the strip fuse with the ignition OFF, but checked the pins with it on. So, I will try testing the fuse with it ON and see what I get there.

I found that AAA will send out a "battery rescue" truck to test and, if necessary, recharge the battery. I think is going to be step one. I did leave the new battery sitting in the back of my other car for a good while, during which it got pretty cold ... I am not real wise about batteries, but I have to wonder if this less-than-intelligent storage plan didn't drain it a bit. I'd take it out and get it tested at Autozone, but I literally can't pull it out ... took all I had to get the old one out and new one in ... being a 105-pound girl DOES have it's disadvantages ...

If that doesn't help ... I'll just tell the battery guys, "go home and send the tow guy.":fork_off:

Have you checked the voltage at the battery? You should just replace the glow strip fuse. Buy a few as they are only a buck or so, replace the one there and keep at least one in the glove box.

Replacing the glow plugs is not particularly fun. With the right assortment of extensions people say that it is possible to do so w/o removing the intake manifold given some patience... Once the intake manifold is off the plugs are easy... but the intake manifold is a pain itself.

Have you tried plugging in the block heater for an hour or so?

Took the battery to AutoZone and they said the charge was low, so it's getting charged. They did say they didn't think that would cause it to not start, and that it was more likely that the charge was low because of all the cranking, but I figured it's NOT going to help matters to have low charge. Getting juiced up as we speak, so maybe that'll be enough ... :o

I'm sure all the cranking along with the cold had helped to weaken the battery, however a low battery will keep the car from starting. You figured correctly about the low charge.

AAA plus is also a good option. I have it and I paid $123 for it.

I take it the car is parked where an extension cord will not reach? I have a 100 foot cord and a battery charger/start booster in my trunk.

I also installed the power cord to the factory installed block heater. I have new glow plugs now, but you almost don't need them if the block heater has been plugged in. The heater can generally keep your coolant/block at 50+ deg C (122+ deg F). Makes for a nice and easy start. In 50 degree weather it should be able to heat the car to 50+ C in just a hour or two.

Obviously this is not a long term solution, but is an option.

-Jim

http://catalog.worldpac.com/mercedesshop/sophio/wizard.jsp?partner=mercedesshop&clientid=catalog.mercedesshop&baseurl=http://catalog.peachparts.com/&cookieid=21M0N4V6G21M0N5A6C&year=1987&make=MB&model=300-DT-002&category=All&part=Block+Heater+Cord

http://www.peachparts.com/shopforum/showthread.php?t=76493

Charging the battery did not help. This car is not going to start. :( I'll give it a few hours to see if the temperatures come up (it's still 40 ... so much for 65), then call AAA.

jadavis ... as far as I know my car does not have a block heater. Plus I have nowhere to plug in ... unless I use A LOT of extension cords!

I just added a link in the post above:
http://www.peachparts.com/shopforum/showthread.php?t=76493

It is a thread that shows the location and how to wire in the heater cord. I also added a link to the heater cord.

Your car came from the factory with the block heater installed. The plug has a threaded cap on it that has kept the pins nice and clean for the last 20 years.

Too bad it is not near an electrical outlet!

-Jim

I had the same problem
 

BohdiBenz,
I had the same problem (along with a hunting idle) and was able to get it started by removing the fuel cap. After I got it to running, it really struggled to stay "alive". When I opened the fuel cap there was a strong "whoosh". I believe it was due to a clogged/inop tank pressure relief valve. Now, it runs as long as I have the fuel cap off. Do that and see if it helps...along with the other suggestions from the others.

Clint

Time to replce the fuel cap. It is supposed to be like a one way air valve. Air is allowed in, but not out.

After you get the battery charged, try checking for +12v at the plugs again. I'm still suspecting the 80A strip fuse. Try removing it... it often comes out in two pieces. If you have at least 3 good glow plugs that are heating, it should at least try to fire, if you let it glow 30-60 seconds. Also crank it with your foot on the floor.

:1blank:

Hey did you get your car started? Has anyone heard from Him?



Cardude

Yes ... :D ... sorry I keep meaning to update, but it's been a crazy weekend (I work weekends). Thursday I tried everything, would not start even when it reached 60 degrees out ... felt like it was getting close, though. So I drove down to my mechanic in my other car to make sure it was OK to have Bodhi towed over there that afternoon. Well, he asked where I was having it towed from, and I told him it was only about half-mile away (I had just moved recently) ... he knew exactly where my apartment building is, so he just offered to come and get it at the end of the day. I left him with the key, and a few hours later, when I came down to leave for work (I live on the 14th floor), Bodhi was gone. 24 hours later, Bodhi reappeared in my parking lot, the key left with my doorman. :D All fixed, and I'm assuming it was just the glow plugs. I have not had a chance to talk to my mechanic yet, as it was the weekend, but I'll find out tomorrow when I go to pay him. Nice guy ... he went out of his way to help, and got the car back to me without even discussing payment. He knows I'm good for it ... :cool: .

Much thanks for all the help, guys. I'll give another update when I find out exactly what the situation was. I'm curious to know if ALL plugs were bad ... I think they really had to be, because it was SO stubborn.

Hey Bodhi,

Have you tried it with 2 cycles just out of curiousity.

I don't know the firing order off hand but if 1 and 3 come after or before one another that could amplify the problem of having only two plugs out of comission. If it was running fine before they crapped out then you are probably in good shape.
As for the cranking time, Angel has got it right.
It may seem like an eternity but give it a good crank for 5-10 seconds, 15-20 being the max.
After doing a crank like that (or two is okay) then let the starter rest so as not to put it at risk for a burn out. Sit there and fiddle with something else for a minute for good measure.
(Not to insult but when you "key over" the glow plugs two times to really get things hot, naturally wait until the light goes out on both times- then hit the starter-that may be completely obvious though.)
IMHO- MB diesel starters are pretty beefy. They can handle that crank time.

-Pat

This advice is incorrect and unnecessary.

The idiot light has no connection as to the length of time that the glow plugs are powered.

The relay will typically allow for about 35 seconds. It makes an audible and quite loud click when it disengages.

The best procedure is to glow it one time for the full 35 seconds. The second the relay drops out, turn the key to start.

Glowing for another 35 seconds is unnecessary.

Perhaps I am mistaken Brian,
but on my SD the glow plug relay light isn't just an idiot light,
it also stays lit for a varying amount of time in regards to how cold it is.
When it is 30 degrees out it will stay lit for longer than 60.
I believe that it measures in some round about way the resistance and keeps the light lit for shorter/longer depending.
I didn't mean wait for another 35 seconds after the first go around.
Sorry if I was unclear

No big deal- its back and running :)

I just wait for the click. With the exception of this recent situation, that has always worked for me, even when it was below zero degrees a couple of times. I had the darndest time explaining to my dad that you wait for the relay to click ... he kept insisting I was waiting too long, and that that was why the car wouldn't start. He eventually listened, though ... he knows I get my info from good sources. :cool: .

The light will remain on for varying time depending on the ambient temperature. However, the light and the relay are independent.

I don't believe the light is on for 60 seconds on your SD. This would make no sense whatsoever because the relay drops out at approx. 35 seconds.

Thanks for the reply, look forward to hearing your findings from your indie.



Cardude

Thanks Guys,

I definitely learned something on that one.

Did he replace all the glow plugs after all?



Cardude

I believe that if you wait for the relay to time out (loud click) and THEN crank the engine, it will be cranking with no voltage applied to the plugs. I never checked to see if the relay turns the plugs back on when you start cranking or not. The easy way around this is to let it glow until the relay clicks off, then quickly turn the key all the way off, then start cranking immediately. This would re-set the glow cycle and guarantee the plugs are on while cranking.

Note that for models with factory afterglow (all from 1990-up) the timeout is 60 seconds. The 1995-up models have up to 180 seconds of afterglow. This wouldn't apply to the OM617 or the OM603.960/961 engines in stock form.

Here's the FSM section on the afterglow function, complete with neat graphs of the time/temp relationships, etc and all the factory data:
http://www.w124performance.com/service/w124CD1/Program/Engine/602_603/15-0705.pdf
(~400kb PDF file)

:kid:

As far as I know, Dave, the violet wire will immediately drop the relay when the key is turned to the #3 (start position).

So, if you're fast on the key, you might be one second late as compared to the normal start sequence before the relay shuts down.

It's not worth the trouble to recycle the key to save one second of glow time.

Brian, I'm nearly certain that the glow plugs remain energized while cranking. I believe the violet wire drops the relay when the key is released from #3 (cranking) back to #2 (run). I'd have to double-check that though.

:dizzy2:

Interesting Dave.........but.........that would make for quite a complicated relay.

I've got to check it myself..........I always thought they were off during crank.

Now, you've got me wondering..........:confused:

Yeah - me too!!!

:speechles

I perused the original post quickly, so if I missed it I apologize, but have you done a compression check on this engine?