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  #16  
Old 12-31-2012, 10:05 AM
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if you don't have a block heater, you can set a 100watt or so incandescent shop light on the head and let it soak heat into the engine for a few hours...
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  #17  
Old 12-31-2012, 10:19 AM
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Is winter blend fuel less viscous than summer blend? Here's what I'm thinking. It's been documented on here that WVO will wear out an IP and when it does, the engine will run on WVO but not on diesel since the diesel is thinner and won't compress in the worn IP (I think). If that is what has happened and if winter blend is thinner than summer fuel, it's quite possible he picked up a tankful of winter fuel on the trip between the CA coast and the Colorado Plateau. And that fuel is causing the problem. An unlikely scenario, but possible. It doesn't account for the 'wont start with ether' issue.
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  #18  
Old 12-31-2012, 10:58 AM
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Quote:
Originally Posted by cooljjay View Post
...I started with wd40 and as my anger grew I began using harsh chemicals...
Many that are new to diesels, and more surprisingly, some who have been around them for years, fail to understand just exactly how a diesel, well, diesels.

These are compression ignition engines. There is no spark, or anything mechanical to initiate ignition, other than sheer compression of air, and timing of the fuel delivery. This last part is very critical, as youll see in a moment.

As the piston moves up its bore on the compression stroke, the air is squeezed to much smaller volume. The compression ratio dictates how much this is, but diesels generally develop compression ratios around 16:1 for direct injection, to around 22:1 for indirect injection. Indirect engines have prechambers, an area outside the main combustion chamber where ignition is meant to take place. Read that again. Ignition is meant to take place INSIDE the prechamber, not outside of it.

As air is compressed it gains in temperature. There are some variables, like the ambient temperature of the air entering the engine, its moisture content, etc., but in general terms, a diesel is designed to generate air temperatures during compression, that greatly exceed the flash point temperature of diesel fuel.

As we know, the diesels fuel system is carefully timed to inject fuel at a specific moment, which is approx at the point the piston reaches top dead center. A little early is okay if pressures dont build too rapidly before the piston passes TDC and begins its downward push. But too early can be hard on the engine, in fact it tries to stop the pistons upward movement, or reverse it.

Up the point of injection, the air that was drawn into the cylinder and which is being compressed, is inert, at least in the context of being flammable or combustible. At least it should be. Therefore, the fuel that is sprayed in by the injection system needs to be timed correctly.

However, if another fuel of any sort, including blow by fumes from the crankcase, has a flash point below the ignition temperatures reached in the combustion temperatures of compression, which can exceed 1000F, is mixed with the incoming air, it will detonate exactly as its ignition temperature is reached. And that is the great danger of adding fuels like WD40 and Ether, or any other fuel, to the intake air. First, those fuels do not burn as slow as diesel, they detonate more explosively. Second, as there is no way to control when this happens, it could happen at half stroke, and literally reverse the engine and make it run backwards. Or, it could simply bend the connecting rod, crack the piston, crack or damage the prechamber, break the glow plug, or worse, do any or all of that damage and then, take off running backwards. Running backwards the engine starves for oil while sucking unfiltered air in through the exhaust and blowing exhaust out the air filter. Its a real mess.

Using starting fluid to start direct injection diesels is not as critical as they have much lower compression ratios. And this is where a lot of the misinformation stems, the thinking being if it works on one diesel, it works on all, a quite dangerous mistake. Therefore the best advice is simply to avoid using those fluids at all, but to definetly not use them on indirects. The engine you save may be your own, or your life!

Rudolph Diesel was injured by one of his engines, some say almost killed, due to the pressures that developed during a test, exploding the engine and throwing shrapnel. Many others down through time have been injured or killed by diesels, or blown them to smithereens, by failing to understand their true capabilities. Older Detroit Diesels have a long history of runaways, taking off one their own oil fumes due to a damaged piston or some other failure, and revving to speeds that bring about total destruction, even after the fuel was shut off.

Mercedes are pretty tough. I never heard of one blowing up. But they do break internally. And just because the engine runs after such starting treatment, does not mean it wasn't damaged by it. A cracked piston can run a long time without making itself known, as can a cracked PC or broken glow plug. Even a slightly bent rod can be hard to diagnose, or even be aware of.
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  #19  
Old 01-07-2013, 08:27 PM
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well I am nit giving up on this car!

I had another guy come by and give it a look. His first reaction was its low compression....sick of hearing that! The thing started fine before it sat a month. So I cranked the engine over for him, and he's like yep it sure isn't cranking fast enough.

he then looked at my battery cables and they were 10 gauge and very worn...so he went and got some 12 gauge ones and it started cranking a bit faster!

people are telling me that's its not a oil problem, but I beg to differ. I think that after a 900 mile drive at 75mph that the oil became all gunked up with carbon from sitting, having tight valves and running wvo....my friend ran a tank of bio through it to before my trip.

so I think the oil is just to thick to flow and the cold isn't helping.

so I am changing the oil! I am fearful of doing a 100% synthetic change so I am going to do a 50/50.

I also ordered a new set of glowplugs...mine test good in the car but I have no idea how many miles are on them nor the brand. I will remove them and squirt a little oil to soak down into the rings to clear up any sticking issues.

last resort will be starter!

if I have to graft a Honda onto the front end of this girl I will lol
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  #20  
Old 01-07-2013, 08:35 PM
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Quote:
Originally Posted by cooljjay View Post

people are telling me that's its not a oil problem, but I beg to differ. I think that after a 900 mile drive at 75mph that the oil became all gunked up with carbon from sitting, having tight valves and running wvo....my friend ran a tank of bio through it to before my trip.

so I think the oil is just to thick to flow and the cold isn't helping.

so I am changing the oil! I am fearful of doing a 100% synthetic change so I am going to do a 50/50.

l
If that works, you'll need to send your resume to Benny Hinn so you can be his assistant.
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1985 409d 65k--sold 06
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  #21  
Old 01-07-2013, 08:49 PM
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Quote:
Originally Posted by cooljjay View Post
well I am nit giving up on this car!

I had another guy come by and give it a look. His first reaction was its low compression....sick of hearing that! The thing started fine before it sat a month. So I cranked the engine over for him, and he's like yep it sure isn't cranking fast enough.

he then looked at my battery cables and they were 10 gauge and very worn...so he went and got some 12 gauge ones and it started cranking a bit faster!

people are telling me that's its not a oil problem, but I beg to differ. I think that after a 900 mile drive at 75mph that the oil became all gunked up with carbon from sitting, having tight valves and running wvo....my friend ran a tank of bio through it to before my trip.

so I think the oil is just to thick to flow and the cold isn't helping.

so I am changing the oil! I am fearful of doing a 100% synthetic change so I am going to do a 50/50.

I also ordered a new set of glowplugs...mine test good in the car but I have no idea how many miles are on them nor the brand. I will remove them and squirt a little oil to soak down into the rings to clear up any sticking issues.

last resort will be starter!

if I have to graft a Honda onto the front end of this girl I will lol
My experience is that low compression will result in faster turning of the engine during start.

Larger gauge wires are always a good thing.

Don't take anyone else's word, change the dang oil... and don't bother with 50/50 put in good old inexpensive dino to satisfy the requirement of removal-of-oil-from-list-of-potential-problems.

tank of bio.... sounds like fuel filters are in your future. Bio is an excellent detergent, and will free up an amazing array of crud in your fuel system.

Before you replace the glowplugs, give 'em 12v on a bench... and make sure the wiring is clean and tight. Many a glow plug has been tossed because the wiring was insufficient... ask me how I know...

Best of luck!!
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  #22  
Old 01-07-2013, 08:52 PM
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Quote:
Originally Posted by vstech View Post
if you don't have a block heater, you can set a 100watt or so incandescent shop light on the head and let it soak heat into the engine for a few hours...
I've parked a 500w halogen construction lamp under the oil pan....

Works almost as well as a block heater...
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On some nights I still believe that a car with the fuel gauge on empty can run about fifty more miles if you have the right music very loud on the radio. - HST

1983 300SD - 305000
1984 Toyota Landcruiser - 190000
1994 GMC Jimmy - 203000

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  #23  
Old 01-07-2013, 09:03 PM
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Quote:
Originally Posted by cmbdiesel View Post
My
tank of bio.... sounds like fuel filters are in your future. Bio is an excellent detergent, and will free up an amazing array of crud in your fuel system.

Before you replace the glowplugs, give 'em 12v on a bench... and make sure the wiring is clean and tight. Many a glow plug has been tossed because the wiring was insufficient... ask me how I know...

Best of luck!!
don't have to worry about that, everything from the tank to the injectors were replaced....and all the lines steamed...so no crud for it to break down!

here's a thread I started when I got it...
My new 300D...plus headache.... - Benzworld.org - Mercedes-Benz Discussion Forum

oh will do! Some had a high ohm reading so I will pull them and test em. Then any good ones will be spares!
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  #24  
Old 01-12-2013, 05:54 PM
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well did the oil change, rechecked glow plugs....replaced the starter....tried to use wd40 and ether....still will not pop off....she cranks a LOT better then she did....I get white smoke out of the rear so shes getting fuel but the engine just wont catch....I'm at a loss of what to do next.....
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  #25  
Old 01-12-2013, 05:56 PM
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How did you check the glow plugs?
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  #26  
Old 01-12-2013, 06:59 PM
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Quote:
Originally Posted by kerry View Post
How did you check the glow plugs?
ohm test, jumper cables.....even ordered a new set....


I am workimg on resetting the ip timing but its getting dark n cold so i have to call it a night....
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  #27  
Old 01-12-2013, 10:51 PM
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Looking at the original thread on the car, I'd say the crap that was run through that engine int he past could easily have gunked up the rings. I'd say a compression test is in order.
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1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13
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  #28  
Old 01-12-2013, 10:52 PM
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If it's not firing on ether, I don't see how it can be a poorly timed IP.
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1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13
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  #29  
Old 01-12-2013, 11:32 PM
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My 240D used to blow a lot of white smoke on cold weather cold starts if not plugged in. It would pretty well fill up the space between my building and the next one over as it started hitting on one cylinder, then two, then all four. That car had about 220,000 when I got it and 240,000 when I got rid of it. I never did check the timing, or the injectors, or the compression, though I suspect none of them were ideal. I did adjust the valves, and that helped, but not a lot, since they weren't very far out of adjustment.

I have seen diesel engines in good condition not start on ether because the ether wasn't introduced into the intake in such a way as to provide vaporized ether to several cylinders. Spraying it in while the engine was cranking sometimes worked and sometimes didn't. Spraying a little in a non cranking engine, waiting a bit for it to vaporize and spread around, and then cranking was more likely to get combustion. Not that I am advocating use of ether in an OM617, just saying that an engine that doesn't crank on ether may still be ok.

My best guesses are low compression, retarded injection timing, or (not sure if this was checked already) no power to glow plugs. The last one is easiest to check. Timing is next, and compression the most involved, especially since the OP hasn't obtained a compression tester yet.

Edit: Just re-read the whole thread. Probably not the plugs. Timing (valve and injection) checks would be my next step (maybe it jumped a tooth?). If those check out, I would check compression. If that checks out I would seek out a replacement injector pump. Used ones should be relatively inexpensive at the junkyard, potentially free if you're creative
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  #30  
Old 01-12-2013, 11:40 PM
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If you are running 12 gauge wire to the starter that is what is used in house wiring. and is good for 20 amps. Not a couple hundred that the starter wants. Even the glows are fused at 70 or 80 amps.

12 gauge is thinner than 10 gauge (30 amp). The wire you use should be at least 5/16" thick plus the thickness of the insulation.

Do your glow plugs actually glow. They can short internally and have low resistance and not work effectively.
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