Intermittent Fuel Leak on 2006 2500

**BillTomko** · 02-23-2011, 05:03 PM

Hi Everyone,

I own 2 Sprinters, an 04 and 06. My 06 has a bizarre fuel leak that I cannot seem to find/stop. I have already replaced the 2 very short sections of fuel line near the front of the fuel rail, followed by a thorough engine cleaning and added a UV fuel dye.

And now the weird part--it only leaks on the first cold start of the day. I start my day early (read in the dark) so I don't have an opportunity to look at that time. A careful under-hood inspection later reveals nothing, not wet, and no UV indicator. I have been able to see the fuel drip out in the dark, see the fresh fuel in the driveway, and smell the fuel in the cab. It's like it squirts out directly onto the pavement without getting on anything under the hood.

Any ideas at all would be much appreciated!

Thanks In Advance,
-Bill

**flman** · 02-23-2011, 06:39 PM

Screws are falling out of the back of the pump. Happens in cold weather after a couple of years. You need to remove it to tighten them back in, and put on a little loctite. I did it on the 05, but I did not split the pump, cause you never know what might happen.

**BillTomko** · 02-24-2011, 06:52 AM

Thanks Bob,

I'll look at it this afternoon and report back.

-Bill

**flman** · 02-24-2011, 01:55 PM

Did you notice any wetness in the V area of the pump? It leaks between the aluminum body and the cast iron body.

**BillTomko** · 02-26-2011, 01:07 PM

Hi Bob,

No wetness there. The fuel appears to be coming from that area but more below where you cannot see it. The front of the block is wet, but not any of the pulleys or the belt.

I was, just now attempting to remove the high pressure pump by removing the three inverse torx bolts. I loosened all three and removed the one at the 3:00 position first. Surprisingly, it was not a bolt but a plug with a spring (maybe part of a pressure regulator). So I tightened everything back up.

This begs the question: "Does the low and high pressure pump assembly come off as a unit which then be disassembled?"

Dripping Trucks Want to Know....
-Bill

**flman** · 02-26-2011, 03:22 PM

So did you remove it? Did you get the bolt at the bottom, the one that is a real PITA?

Look Here:

Injection pump leak - Sprinter-Forum

**BillTomko** · 03-02-2011, 04:59 PM

You were dead on Bob. Two of the torx bolts literally fell out when I removed the pump assembly. I cleaned it all up without tearing it down, as warned. Then I buttoned it back up with loctite. First cold start the next morning was clean, tight, and dry.

Don't get me wrong, this was a PITA as you have to remove a lot of stuff. But I would guess it is within the capabilities af a decent shade tree mechanic. Plan on a whole day and I wouldn't recommend doing it on a hot engine.

Thanks Again Bob,
-Bill

**flman** · 03-02-2011, 06:16 PM

The bolt on the bottom was the worst for us, I had the E10 in 3/8 drive, which would not fit due to how close it was to the casting, we ended up using a 6 pt. 5/16 on a 1/4" drive. I have ordered an E10 x 1/4 since that just in case from Wia Tools.

The same for us, a couple of the bolts fell right out, at least they cant get lost while you are driving.

But I give Abbitabender AKA Dr.A from Sprinter Source the credit for being dead on with this diagnosis.