96 E300 leaking air, bubbles in the lines - PeachParts Mercedes-Benz Forum

kinghais · #1 10-06-2010, 09:54 AM

My 96 E300 is leaking air .when the engine is off I c large bubbles in the lines, n when it's running I c bubbles running in all the lines.
I have changed the the filter n pre-filter, with new O-rings.
Yesterday I changed the Strainer n that strainer was dirty as hell!!! N the tank, when I pulled out the strainer I saw stuff like Black Mod was dripping out my tank so I just put my finger in there n pulled out alot of that stuff n I don't think I took out everything cause I only could put my finger in it.
I'm planning to take my tank out n flush it when I get time.
So after I change the strainer, it start up k n Bubbles still in the lines

Ahhh !
I really need help I can't think about anything else. My last chance is the fuel lines, I'm gonna change the fuel lines, but idk which ones, which lines I need to change???
Is it poosible that my tank is too dirty n cause this problem???
Help please

tankowner · #2 10-06-2010, 11:00 AM

Quote:

Originally Posted by kinghais

My 96 E300 is leaking air .when the engine is off I c large bubbles in the lines, n when it's running I c bubbles running in all the lines.
I have changed the the filter n pre-filter, with new O-rings.
Yesterday I changed the Strainer n that strainer was dirty as hell!!! N the tank, when I pulled out the strainer I saw stuff like Black Mod was dripping out my tank so I just put my finger in there n pulled out alot of that stuff n I don't think I took out everything cause I only could put my finger in it.
I'm planning to take my tank out n flush it when I get time.
So after I change the strainer, it start up k n Bubbles still in the lines

Ahhh !
I really need help I can't think about anything else. My last chance is the fuel lines, I'm gonna change the fuel lines, but idk which ones, which lines I need to change???
Is it poosible that my tank is too dirty n cause this problem???
Help please

Your tank being dirty may be a problem, but it is not the source of the air in your fuel lines. Your air leaks are more than likely coming from the plastic fuel lines (fitted with o-rings) going to and from the fuel filters and the injection pump. The o-rings flatten out and degrade over time letting air in and fuel out. What you need to do is determine where the fuel is seeping out. Have you noticed any small leaks? Or the smell of fuel when the engine is running. Often times it is difficult to tell exactly where a leak is because the surrounding area has been covered in fuel. The best approach is to get yourself a can or two of brake cleaner and clean down the injection pump and fuel filter housings. Once dry, start up the car and look to see if fuel starts seeping out anywhere. Specifically, watch the connection points for the fuel lines and also inspect around the delivery valve on top of the injection pump. Another potentially leak prone area is the fuel ("lift") pump on the injection pump - there are o-rings there as well that can go and cause head aches.

With that much air in your lines - are having trouble with the engine stumbling? Also, are you experiencing pressure build up in the fuel tank such that when you remove the cap to fill up you get a big wooosh of air coming out?

kinghais · #3 10-06-2010, 11:48 AM

Quote:

Originally Posted by tankowner

Your tank being dirty may be a problem, but it is not the source of the air in your fuel lines. Your air leaks are more than likely coming from the plastic fuel lines (fitted with o-rings) going to and from the fuel filters and the injection pump. The o-rings flatten out and degrade over time letting air in and fuel out. What you need to do is determine where the fuel is seeping out. Have you noticed any small leaks? Or the smell of fuel when the engine is running. Often times it is difficult to tell exactly where a leak is because the surrounding area has been covered in fuel. The best approach is to get yourself a can or two of brake cleaner and clean down the injection pump and fuel filter housings. Once dry, start up the car and look to see if fuel starts seeping out anywhere. Specifically, watch the connection points for the fuel lines and also inspect around the delivery valve on top of the injection pump. Another potentially leak prone area is the fuel ("lift") pump on the injection pump - there are o-rings there as well that can go and cause head aches.

With that much air in your lines - are having trouble with the engine stumbling? Also, are you experiencing pressure build up in the fuel tank such that when you remove the cap to fill up you get a big wooosh of air coming out?

It starts ok but some times have have hard time like shutting off .
It seems like when my car sits for long time it will have hard time to start cause the air in the lines gets bigger.

kinghais · #4 10-06-2010, 11:53 AM

N I never pay attention to that sound when I open the cap but I think I never heard it in my diesel. I'm gonna c it this time when I fill up.

tankowner · #5 10-06-2010, 02:31 PM

Quote:

Originally Posted by kinghais

It starts ok but some times have have hard time like shutting off .
It seems like when my car sits for long time it will have hard time to start cause the air in the lines gets bigger.

If the car isn't shutting off as soon as you turn the key off, then you have a vacuum problem - and perhaps problems with other vacuum consumers on your car (door locks, brake booster, tranny shifts, etc).

It makes sense that if your car sits longer you will get more air in your lines. If you have a leak somewhere, you typically get fuel coming out when the car is running and air being sucked in when it is not running. THe fuel will drain back into your tank and it will take longer to primer the pump and lines when you do try to start it. You'll need to clean everything up and determine what is leaking. Take pics if you want and post them here.

Bill Ladd · #6 10-06-2010, 03:53 PM

Quote:

Originally Posted by tankowner

If the car isn't shutting off as soon as you turn the key off, then you have a vacuum problem

'96 e300 -- first year for electronic fuel shutoff.

kinghais · #7 10-06-2010, 03:59 PM

I'll post some pics tomorrow

tankowner · #8 10-06-2010, 04:37 PM

Quote:

Originally Posted by Lux

'96 e300 -- first year for electronic fuel shutoff.

Thanks Lux. Yeah, it's worth pointing out that I am not familiar with anything newer than my '95 - so take it with a grain of salt. Others on here with your same model will respond. However I believe the fuel lines are very similar - as are the problems that develop.

notfarnow · #9 10-06-2010, 08:05 PM

If it's running/stumbling a bit before shutting off, then it's likely the o-ring behind the shut off valve. Are you getting a check engine light too?

You may just want to replace that 0-ring and then the other fuel line o-rings (or the plastic fuel lines... sometimes they leak between the black fittings & clear lines). Either way, someone is bound to post that you have to remove the intake manifold to change them... you don't. You just need to remove the fuel filter housing & windsheild washer bottle, and you'll have more than enough room to get at everything

TMAllison · #10 10-06-2010, 10:04 PM

Quote:

Originally Posted by tankowner

Thanks Lux. Yeah, it's worth pointing out that I am not familiar with anything newer than my '95 - so take it with a grain of salt. Others on here with your same model will respond. However I believe the fuel lines are very similar - as are the problems that develop.

Your 95 also uses an electromagnetic shut off valve......The OP should consider changing the SOV oring first and while there all the orings that connect to it as well. If its worth doing one its worht doing all of them. My .02.

Once you have access to the valve, it is easiest to pull it out with lines attached as a unit and work on it on the bench rather than hunched/reaching up under the IM replacing individual orings.

shoe · #11 10-06-2010, 10:13 PM

Quote:

Originally Posted by Lux

'96 e300 -- first year for electronic fuel shutoff.

Lux hows that new car running? Hope all is well

Bill Ladd · #12 10-06-2010, 10:32 PM

Quote:

Originally Posted by shoe

Lux hows that new car running? Hope all is well

Awesome!! Haven't lifted a finger on her except to replace the shifter indicator bulb.

kinghais · #13 10-06-2010, 11:35 PM

I don't even have Check Engine Light, I mean maybe there's but I never c that light.

kinghais · #14 10-06-2010, 11:43 PM

Y not I was planning to remove that intake n other stuff so I can c everything clear ,
N where is SOV???
n wut is Shut Off Valve???

tankowner · #15 10-07-2010, 12:23 AM

Quote:

Originally Posted by TMAllison

Your 95 also uses an electromagnetic shut off valve......The OP should consider changing the SOV oring first and while there all the orings that connect to it as well. If its worth doing one its worht doing all of them. My .02.

Once you have access to the valve, it is easiest to pull it out with lines attached as a unit and work on it on the bench rather than hunched/reaching up under the IM replacing individual orings.

Terry, I was hoping you would chime in, however, I don't really follow you here. Perhaps I am missing something, but the SOV on my IP is vacuum operated. The 210 set up must differ more from the 124 than I imagined. Regardless, I guess my input is to clean it up and figure out where the leak is coming from. Listen to the W210 guys and take Terry's adivce to change out as many o-rings as you can while you are in there.