1999 E300 turbo diesel, found leaks, replace o-rings, no leaks. When cranking there areno air bubbles are visible going into the fuel filter while. If and when the engine finally does start it dies within 30 seconds and just as it is dying, lots of air bubbles appear running into the fuel filter.
No visible fuel leaks at all, don't I need to have some leaks to be having air bubbles? Fuel flow is good to the fuel filter as I have an inline/external fuel pump hooked up. I have no bubbles passing in line going into the filter.
I don't understand how there can be no airbubbles at one moment and then they all of a sudden appear
Pulling my hair out on this one.
Any advice as to where to start this troubleshooting would be greatly appreciated.

 

Replacing orings only on aged plastic seats seldom leads to success.
Get whole new lines and don't forget SOV oring.

 

Thank Kajtek1, I understand completely, I live in Central America, Panama, have to make do with what I have at my current place, moment in time. I found some o-rings here that weren't MB o-ring and now I do not have any leaks.....at the moment that was my primary concern. Now I have another issue and maybe it is related to the old lines or the non-MB issued o-rings. I am ordering some lines on the internet and when they make it to Panama I will install them and go from there. To me, I don't understand why I am getting air bubbles after I have been cranking the car over multiple times, (very hard starting) to get it running and then the bubbles appear after about 30 seconds or more of running, then the air bubble come and the car dies. I have seen many threads and I read most of them before I posted mine, but not finding the solution to my problem has me beating my head against the steering wheel. Thanks again and if you have some more input all I can say is thank you and I have a cold beer waiting for you when you get here !

 

I recall nice topic with picture about the system on benzword.
I sold my last OM606 about 10 years ago, so memory is fading, but recall about 4 active tubings + thermostat tubing, who is hard to replace.
The 2 tubings up to priming pump operate with vacuum and that is where the leak will suck the air.
From priming pump the fuel is under the pressure and any leak will show as fuel outside.
At the time set of tubings was about $40 and after pulling washer reservoirs out, I could do them all without any more parts removal.
The 3rd time it become like 20 minuets job. Top off the tank after the job for easy restart.
Central America? Panama? Ecuador still is on my bucket list, but lack of good diesel fuel for my Sprinter in some countries is delaying the departure.

 

Panama . Getting to Equador by road is a bit more challenging than Panama as you have to put your vehicle on a boat and float it from Panama to Colombia as there is not road(yet) connecting the two countries. Many people do this and drive all the way down to lands end, Tierra del Fuego.
It's hard to imagine that there would be any problems as you say with the availability of diesel fuel because every semi truck traveling needs diesel and a high percentage of vehicles on the roads down here are diesels. Maybe it isn't the lack of diesel fuel, but the lack of what is considered good diesel. I do see plenty of the newer Sprinter vehicles here that are used as VIP transportation or for the upscale people movers. I guess you could pack along some diesel additives for such a problem. Do it! No time like the present, only Covid may add another page to the normal basic logistics.
The drive down, through Mexico and Central America was wonderful....epsecially if you like to surf . I did it in 2008, speaking Spanish helps a ton and having a couple of big black dogs with me riding shotgun was also helpful. Let me know if you need some detailed info about the trip. PM me. I would do it again in a heartbeat.

Thank you for the great info, every little bit helps as I almost always learn something each time I read the informative posts/threads/comments. I will look again/further on Benzworld, I do remember seeing some great threads and I remember one with details and photos but I don't remember anything about 'two tubes up to a priming pump'. I am not sure my car has a priming pump??? Originally I found a very leaky fuel line at the fuel filter, not sure what the particular line is called, but it wasn't the one coming in from the fuel tank. It was one of the other two there where there are three horizontal to each other at the top side of the fuel filter. I fixed that leak then found a leak from a lower spot, below the intake manifold where the is a black plastic piece(fuel shut of valve?) bolted to the side of the motor. I thought it might be coming from a line attached to this valve and removed the intake to have better access and then saw it wasn't coming from any line but from between the valve and engine block. I fixed this leak by replacing the o-ring on this valve. Once I got everything back together the car didn't want to start but when I finally did get it started it wouldn't run for more that 30 seconds or so. I could see that I didn't have anymore fuel leaks, but for the life of me I can't figure out why the air bubbles appear after the engine runs for the short period of time that it does. I will have to search out more diagrams for this car and see if there is a priming pump with vacuum lines as you say where the sucking of air could be coming from. Man that would be great if this is where problem it coming from. I suppose I could have easily have knocked of a vacuum line. I do remember two vacuum lines but want to say they were connected to a lower part connected to the underside of the intake manifold.
I found a set of tubes online/ebay and having them sent down. I don't remember if they come with new o-ring and guess I should have checked that before I hit 'pay now'. I now look for a proper replacement o-ring for where the fuel shut off valve enters the engine block. I don't have a leak there any longer but I have put two skinny o-rings to replace the original single fatter one that was leaking, because that is all I could come up with. No leak there but I suppose it would be good to have an original replacement or equivalent.

Thanks again Kajtek1 !!

 

https://www.benzworld.org/threads/di.../#post-3494325

Line 1, 2, 3 lead to priming pump and work under vacuum.
I keep you offer in mind if I go south. So far reports from Mexico say you can buy ultra low sulfur diesel only at Mexican border, when down the country it is gambling. Modern diesels don't like old fuels.
Thanks for the offer.