Tandem pump replacement

I have searched for a "how to" for replacing the Tandem pump on my '04 PD Wagon with no success.
If anyone can direct me to a how to, or help me out, it would be greatly appreciated.

Thanks!

Lift up right rear back seat bottom. Unscrew the three philip screws holding the round cover plate on. Remove plate. Unplug electrical connector from pump. Disconnect fuel lines (2 of them) from the pump. Bentley says just to push the tabs on them and pull apart. One member said it was not easy doing this. Mark the location of the rubber rataining ring/collar on the car body and on the the old pump/sending unit. Bentley calls for a special VW tool XXXXX, a BIG spanner, to remove the rubber collar. Improvise. Take a 2 X 4 or a large screwdriver or crowbar and mallet and knock the collar counterclockwise to unscrew it. Remove collar. Slowley lift the old pump out, draining as much fuel as possible back into the tank. Make sure the rubber gasket does not fall into the tank. Have a bucker handy to put the old pump into.

I think the new pump should have the fuel float and sending unit on it. Put it into the tank, using the old gasket. Make sure its orientated (rotated) the same way the old one was. Screw on and tap tight the rubber collar. Plug the fuel lines back on. Plug in the electrical connector. Start up the car and run it to ensure it works and that the fuel lines do not leak. Screw the round cover plate back on. Lower the seat.

I'd also lift up the seat after driving for a little while unscrew the plate for a peek and then again after filling the tank, to make sure diesel is not leaking around the new fuel pump where it fits into the tank.

--Nate

Tandem Fuel Pump

The tandem fuel pump is NOT in the tank! The tandem pump is on the cylinder head and consists of two sections, the vacuum pump and the fuel pump according to Bentley manual.
Remove engine cover-Disconnect MAF connector, breather hose,air guide hoses & remove air filter housing.
Disconnect fuel supply hose & return hose from fuel filter. Connect hand vacuum pump to fuel return hose. Operate until no more fuel runs from return hose. Disconnect brake booster vacuum line from tandem pump. disconnect fuel supply hose & fuel return hose from tandem pump. Remove mounting bolts. Remove tandem pump from cylinder head. Install in reverse making sure pump coupling has proper seating in camshaft. Always replace tandem pump gasket. Torque upper mounting bolts 20Nm(15 ft-lb), Lower bolts 10Nm(7ft-lb) This is from Bentley

It would take more time to read this thread than it would to just replace it...it is that simple.

Yes, the tandem pump is on the head, NOT in the fuel tank. That is the lift pump.

Giovanni----Do you have a BEW motor? If so, why are you replacing this component? Ho many miles on it? what was the failure mode? Not under warranty? Sorry for all the queries, but I have a BEW in an '04 jetta wagon, and I have been watching for a thread about tandem pump failures and the result. Can you smarten me up?

2004STARWARSTDI said:

The tandem fuel pump is NOT in the tank! The tandem pump is on the cylinder head ...

Click to expand...

Opps. Yea. I read "tandem", but my brain was thinking "lift" pump, since they are so problematic in the PDs.

To many fuel pumps!

--Nate

Check your VIN as there was a recall on them.

2004Nick said:

Giovanni----Do you have a BEW motor? If so, why are you replacing this component? Ho many miles on it? what was the failure mode? Not under warranty? Sorry for all the queries, but I have a BEW in an '04 jetta wagon, and I have been watching for a thread about tandem pump failures and the result. Can you smarten me up?

Click to expand...

Yes I have the BEW engine with 110,000km now on it. I have called VW Canada and they tell me that there was no recall on this car for the tandem pump, that't it... in there eyes!!

I do not agree. I have read many threads where people have had problems with these pumps. Apparently mine does not fall in the VIN for the recalls.

I am having problems with hard starts after sitting over night or long periods. One mechanics solution was to replace the Tandem pump, since the in tank fuel pump has already been done, and fuel filter.

Hey 2004STARWARSTDI.....
Is there any talk about repriming the fuel line once the tandem pump is installed?

Thanks.

The tandem pump recall was for mid-year 2004s and early 2005s. Mine did not fall into the VIN range, its an EARLY 2004 (oct 2003 build date). If your car did not fall into the range, you would have never received a recall notice from VW. Now if it did fall in the VIN range, you may not have received a notice either

--Nate

Tandem Pump Replacement

As i recall, there was a thread describing one failure mode
of the TANDEM pump being that it leaked down into the
CYLINDER HEAD (YIKES) AND THUS SOMEHOW INTO THE COMBUSTION CHAMBER! Is this possible? anyway resulting in a hydrostatic lockdown causing all sorts of problems! if anybody has time to research this case I would really like to hear more about it. As in "can the T. Pump be diagnosed before this could happen?" Nick in BC. I think the tech working on this cas was in Texas, that's all I remember.

Repriming the system after the tandem pump replacement:
1) clamp off fuel return line from filter to tank (blue markings on it)
2) remove the fuel return line from engine to the filter at the filter and cap off the nipple from which you removed the hose
3) use a hand vacuum pump with a suitable clear container or hose between the vacuum pump and the fuel line to draw fuel through the new pump and cylinder head and return line until you see fuel has come through.
4) reinstall fuel line on filter/t-fitting nipple
5) unclamp fuel return line

MoGolf answered your priming question.

2004Nick said:

As i recall, there was a thread describing one failure mode
of the TANDEM pump being that it leaked down into the
CYLINDER HEAD (YIKES) AND THUS SOMEHOW INTO THE COMBUSTION CHAMBER! Is this possible? anyway resulting in a hydrostatic lockdown causing all sorts of problems! if anybody has time to research this case I would really like to hear more about it. As in "can the T. Pump be diagnosed before this could happen?" Nick in BC. I think the tech working on this cas was in Texas, that's all I remember.

Click to expand...

I believe this is only a problem on the newer 16v 2.0 TDi engines. A friend who is a mechanic in a dealer has just replaced an engine under warranty where it caused a runaway engine.

Tandem Pump Replacement

Thanks for sorting me out on that one, Mickey--i'll calm down now. Nick in BC (I should probably stop reading all this stuff.)

Tandem Pump replascement

I finally found the thread I was half-remembering, Micky.
It was called "hydrolock and lots of fluid" and it boiled down to joeschoonover74's very interesting post that it was
specific to the pump, and not the engine, that caused the crankcase to fillup with fuel! Yowsah! A Bosch, I think, but read it for yourself. I'm too dumb (and tired)to figure out
how to work the quote thing. Nick

There have been a few cases of 1.9L (BEW and BRM) and 8V 2.0L (BHW) PD TDI engines (available in North America) where the fuel has gone into the crankcase (failed injector o-rings?) with disasterous results.

Tandem pumps have leaked externally usually with the fuel dripping onto nearby coolant hoses causing deterioration of the hose and resulting coolant leak.

MOGolf said:

Tandem pumps have leaked externally usually with the fuel dripping onto nearby coolant hoses causing deterioration of the hose and resulting coolant leak.

Click to expand...

Yeah this happened to me last week

EXTERNAL leaks I can take; it's the deadly internal kind that keep me awake at night----anybody know of the internal kind that result in fuel in the CRANKCASE? If so, please step up to the plate! Nick in BC

I wonder if frequent oil level checks could help here. A sudden rise in the oil level and a diesel fuel smell would be telltale.

--Nate

2004STARWARSTDI said:

The tandem pump is on the cylinder head and consists of two sections, the vacuum pump and the fuel pump according to Bentley manual.
Remove engine cover-Disconnect MAF connector, breather hose,air guide hoses & remove air filter housing.
Disconnect fuel supply hose & return hose from fuel filter. Connect hand vacuum pump to fuel return hose. Operate until no more fuel runs from return hose. Disconnect brake booster vacuum line from tandem pump. disconnect fuel supply hose & fuel return hose from tandem pump. Remove mounting bolts. Remove tandem pump from cylinder head. Install in reverse making sure pump coupling has proper seating in camshaft. Always replace tandem pump gasket. Torque upper mounting bolts 20Nm(15 ft-lb), Lower bolts 10Nm(7ft-lb) This is from Bentley

Click to expand...

I'm not looking to resurrect an old thread but to suggest this be listed as a How-To if one hasn't already.
I followed the instructions from 2004STARWARSTDI above to swap out my weeping tandem pump on my 2004 Jetta. Took me about 2 hours from start to finish. Overall, a relatively simple swap out.
As for the startup, I cycled the key about 25 times and did a single crank like Dan mentioned earlier in this thread. It started around the 30 second mark of continuous cranking.

I'm going to be replacing my tandem pump as well, due to a leak. The leak is from the cover of the pump itself.

There is a Transport Canada recall on the pump: http://wwwapps.tc.gc.ca/Saf-Sec-Sur...ft=&ls=0&sy=0&rn=2004435&cf=SearchResult&pg=0

I have a 2004 Golf TDI with PD engine, which would seem to be included in this recall, if you take it at face value.

So I called my local VW dealer (the one I bought the car from when it was new) to ask about the recall. Gave them my VIN, they say there's no recall. I explained that there's a Transport Canada recall, provided the number and asked that they look into it and get back to me to confirm that this recall does not apply to my car. The guy said he'd phone back within a couple hours.

Of course, he never called back. Not even to confirm that my car doesn't qualify for this recall.

Has anyone actually had this recall performed by a Canadian VW dealer?

Anyway, rather than following up on that, I decided it would be worth the $300 to get a pump and install it myself.

I have a 2004 PD, and I did extensive research on this issue - indeed, my VIN is/was within the range of VINs in the recall. However, when I called the dealer & VWUSA, both said there are no recalls for my car.

The key nuance - there are no CURRENT recalls for my car because the recalls ended. ie - VW only had to complete the repairs on faulty tandem pumps for a 5 year period - which ended a few years ago. If you didn't get the repair done within that 5-year timeframe, you still may have a faulty tandem pump, but VW won't pay to fix it.

And, yes, the recall issue was due to a leak at the cover - on LUK tandem pumps. I have a LUK tandem, and it leaks at the cover. Go figure.

There is a rebuild kit available in Europe, for roughly $70, but they generally won't ship to the U.S. All that is really needed is a $5 gasket. But, in the US, we are stuck paying $300 for a whole-new tandem.

As much as I hate leaks, I just let it leak, for now. It isn't gushing out, or I would take more drastic measures.

PS - I consider it highly irresponsible of both the dealer and VW to claim there are no recalls for my car, while failing to mention there WERE recalls, and that my car may STILL have faulty parts needing change, but that VW's window of financial responsibility has ended.

To be clear - I understand the timeframe limitation. It would be absurd if we could go back to the manufacturer decades later and demand free fixes. I just think they should have admitted there were recalls. (I did eventually get VWUSA to admit to this fact, but it was like pulling teeth).

puntmeister said:

PS - I consider it highly irresponsible of both the dealer and VW to claim there are no recalls for my car, while failing to mention there WERE recalls, and that my car may STILL have faulty parts needing change, but that VW's window of financial responsibility has ended.

To be clear - I understand the timeframe limitation. It would be absurd if we could go back to the manufacturer decades later and demand free fixes. I just think they should have admitted there were recalls. (I did eventually get VWUSA to admit to this fact, but it was like pulling teeth).

Click to expand...

Thanks for the explanation about the 5 year limitation on this recall. I did have my car in for other recalls when it was newer, and I'm pretty sure they didn't replace the pump at any time.

My new pump has arrived, so I'll probably throw it in this weekend. Looks pretty easy.

I'm going to re-seal the old one and keep it as a spare.

I would have to disagree with your mechanic and suggest finding a new one. Throwing parts at these cars when you have not taken the time to diagnose what is really wrong gets very expensive. A simple "diesel purge" procedure would have showed if both your in tank lift pump & tandem pump were pumping. Hard starting can be caused by a bad coolant temperature sensor, torsion value (timing) being off, glow plugs. I would tend to disagree that the tandem pumps have a high failure rate. Many of the problems associated with these pumps are leaks not a loss of pumping capacity.

giovanni2 said:

Yes I have the BEW engine with 110,000km now on it. I have called VW Canada and they tell me that there was no recall on this car for the tandem pump, that't it... in there eyes!!

I do not agree. I have read many threads where people have had problems with these pumps. Apparently mine does not fall in the VIN for the recalls.

I am having problems with hard starts after sitting over night or long periods. One mechanics solution was to replace the Tandem pump, since the in tank fuel pump has already been done, and fuel filter.

Hey 2004STARWARSTDI.....
Is there any talk about repriming the fuel line once the tandem pump is installed?

Thanks.

Click to expand...

puntmeister said:

I have a 2004 PD, and I did extensive research on this issue - indeed, my VIN is/was within the range of VINs in the recall. However, when I called the dealer & VWUSA, both said there are no recalls for my car.

The key nuance - there are no CURRENT recalls for my car because the recalls ended. ie - VW only had to complete the repairs on faulty tandem pumps for a 5 year period - which ended a few years ago. If you didn't get the repair done within that 5-year timeframe, you still may have a faulty tandem pump, but VW won't pay to fix it.

And, yes, the recall issue was due to a leak at the cover - on LUK tandem pumps. I have a LUK tandem, and it leaks at the cover. Go figure.

There is a rebuild kit available in Europe, for roughly $70, but they generally won't ship to the U.S. All that is really needed is a $5 gasket. But, in the US, we are stuck paying $300 for a whole-new tandem.

As much as I hate leaks, I just let it leak, for now. It isn't gushing out, or I would take more drastic measures.

Click to expand...

send me the link , i can get the euro parts

Dimitri,
I hunted up the rebuild kit manufacturer about a year ago.

This was the first reference I found which lists 3 different kits.
http://www.ancomnet.gr/en/technical/1922/

Manufacturer is Meat & Doria in Italy.
The bosch rebuild kit was 91108 which their website says was replaced by their part number 91147.
For Luk the first website lists 91109 or 91111. To confuse things the Meat & Doria website says the 91109 was also replaced by the 91147, which doesn't seem right.
Meat & Doria 91111
Meat & Doria 91147


To confuse things more I found another site with pictures that look like the Meat and Doria 91147 and 91111 kits, but seem to indicate they are for Pierburg.
Link Link

I think someone with better language skills than my using google translate may need to try to make sense of all of this.

joelbert said:

Dimitri,
I hunted up the rebuild kit manufacturer about a year ago.

This was the first reference I found which lists 3 different kits.
http://www.ancomnet.gr/en/technical/1922/

Manufacturer is Meat & Doria in Italy.
The bosch rebuild kit was 91108 which their website says was replaced by their part number 91147.
For Luk the first website lists 91109 or 91111. To confuse things the Meat & Doria website says the 91109 was also replaced by the 91147, which doesn't seem right.
Meat & Doria 91111
Meat & Doria 91147


To confuse things more I found another site with pictures that look like the Meat and Doria 91147 and 91111 kits, but seem to indicate they are for Pierburg.
Link Link

I think someone with better language skills than my using google translate may need to try to make sense of all of this.

Click to expand...

it would be easier to get an invite to one of Silivio Berlusconi's bunga-bunga parties than get hold of these kits but I did get one from Germany all quite straight forward except for the metal cover gasket and the double oilseal(vac chamber to fuel chamber) further info if anyone's interested

Stuggling on the bottom 5mm allen bolt. Can't seem to get my rachet in there. What tool combo did you guys find worked the best. Got the other 3 bolts out, just struggling with this one.

I used an old fashioned L shaped allen wrench. Can't remember which bolts I used the long end for and which ones I used the short end on. I do remember it was a little tricky.