Tandem pump leaking, what to replace?

turbocharged798

Veteran Member
Joined
May 21, 2009
Location
Ellenville, NY
TDI
99.5 black ALH Jetta;09 Gasser Jetta
After much research, I am pretty sure my BEWs tandem pump is leaking between the head and pump. Not a big leak, just the head is wet with either oil or diesel fuel on the side. A replacement gasket is around $12, but some people recommend replacing the entire pump (around $350).

I checked the recall and my vin does not fall under the recalled ones although I have the LUK tandem pump without the green dots which is the ones being recalled.

The pump its self seems to be fine. No leakage anywhere on it.

I just spent around $500 for a clutch so I am not crazy about the idea about spending another $350 on a new pump.

My biggest fear is that the old pump fails and pumps raw diesel fuel into the crankcase. That seems to be a pretty rare/non existent failure though.

Thoughts?
 

PDJetta

Top Post Dawg
Joined
Nov 6, 2003
Location
Northern Virginia
TDI
'04 Jetta GLS TDI Pumpe Duce Platinum Grey w/ Leather
My original tandem pump was a LUK too. My VIN was below the range for the tandem pump replacement (car built in October 2003), so my car did not qualify. I can not recall if it had a green dot on it.

I was really impressed with the build quality of the old LUK pump when I disassembled it after replacing it. It was very rhobust and used high quality steel and showed almost no visible internal wear on contact surfaces at 128,000 miles. Like I mentioned in my other post, I would just replace the gasket and like you always should, check your oil level weekly.

The new replacement is a Bosch (stamped with the VW/Audi logo too). If you elect to replace it, a new one is about $250 and about $15 UPS ground shipping from 1stvwparts.com. It comes with a new plate gasket to seal it to the cylinder head. Zeb, who I spoke with there to verify the correct part number, said the pump just seperceeded to a new number and I got the new one. Supercessions involve some type of engineering change, so it may be better than the old one. Like you, I was worried about oil contamination due to what I read about the early pumps, so I elected to buy a new one too. The new part number is 038 145 209 Q (the old one had the same base number and I think ended in "L"). But after taking apart the old one, I think replacing the gasket would have been fine. The top cover was not leaking.

I'd also be woried about any type of fuel leak in that area getting on into the transaxle bell housing and on my clutch and ruining it. I was lucky. I caught my leak so early that the coolant hose running under the tandem pump never got any fuel on it either. Whatever you do, before you remove the old pump, suck the fuel out of the fuel loop and place rags under the pump to catch any spills. Almost no fuel dripped out in my case when the pump was pulled off, though. You do not want diesel on your clutch. My original clutch began slipping bad after I washed the engine using "Gunk" kerosene-based engine cleaner and never recovered. That is how easy it is to get the clutch contaminated.

--Nate
 
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turbocharged798

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Joined
May 21, 2009
Location
Ellenville, NY
TDI
99.5 black ALH Jetta;09 Gasser Jetta
Big thanks for the tips, Nate. I think I will just replace the gasket and motor on. ezvwparts.com has the gasket listed for $7.76. Don't want to pay $350 for nothing. If the pump its self starts to leak, I will replace it when the time comes.

My DMF is shot anyway. I got a sachs G60/VR6 sitting in my basement waiting to be installed. I can see how it can drip fuel/oil right into the bell housing when you take it off.
 

turbocharged798

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Joined
May 21, 2009
Location
Ellenville, NY
TDI
99.5 black ALH Jetta;09 Gasser Jetta
Just wanted to follow up. Since I replaced the gasket, the engine has been bone dry so far. So it appears that the gasket has fixed the leak.

It took a fair bit of cranking to reprime the fuel rails in the head. I put a vacuum on the tandem pump's output line and bled until fuel came out, but I guess there was still air in the head.

So for future reference, if you have a leak between the pump and head, a new gasket will fix it.
 

turbocharged798

Veteran Member
Joined
May 21, 2009
Location
Ellenville, NY
TDI
99.5 black ALH Jetta;09 Gasser Jetta
No, there is a gasket that is internal in the pump that is NOT replaceable and a gasket that goes between the head and the pump that is replaceable.

If the gasket that is internal in the pump goes bad, you have to replace the entire pump. Luckily, I do not have that issue and it appears that it is limited to the ones that were recalled by VW.
 

jetta 97

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Dec 25, 2008
Location
Dallas (McKinney) ,TX ,USA
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2 X Jatta MK5 2006
Turbocharged798,
When you did gasket ,did you have to remove coolant flange or there is space to get pump out with out removing coolant flange like on auto tranny?
 

turbocharged798

Veteran Member
Joined
May 21, 2009
Location
Ellenville, NY
TDI
99.5 black ALH Jetta;09 Gasser Jetta
There was just enough space(barely) to wiggle the tandem pump out enough to get to the gasket without touching the coolant glow plugs. Wasn't exactly one of the easiest things that I have ever done on a TDI.
 
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