Oil pump balance shaft replacement

[waynetdi130]

Hi
I'm looking at getting a new oil pump balance shaft on my 2008 passat 2.0 CR, just wondering is it a big job to change. how much would a garage charge,

Thanks for any advice

[Gazwould]

Only needed if you have the shorter 77mm hex key , some CR are 100 mm.

[JMR1]

When did the change take place from the 77 to the 100 mm shaft?

[waynetdi130]

Hi
Fingers crossed My car has the 100mm Hex but how can I find out, I was assuming it was the newer CR engines that had the modification to the 100mm shaft. Do you know if its a big job to change the balance shaft. cheers

[DMitch16]

Recommend 2 persons for this. Disconnect battery negative lead. Slacken OSF wheel nuts. Jack up car slightly to remove undershield and remove wheel and wheel arch liner. Slacken auxiliary belt tensioner and lock off with suitable "pin" (allen key, drill bit or short handled screwdriver) and remove auxiliary belt noting its rotational direction. Remove timing belt covers and crank pulley. Drain oil. Jack up higher and support with axle stands at suitable points to the rear of the subframe to allow room to work under engine. Disconnect oil level sensor plug, remove sump, remove leftover silicone sealant from sump edge and crank carrier surfaces as you will need to reseal the sump for refitting - their is no sump gasket. At this point you will see the balancer shaft unit bolted below the crank. Lock cams and toothed crankshaft cog at TDC with appropriate locking tools. This also locks the balancer drive cog on the back of the crank gear cog inside the sump area. Support balancer unit and undo the 8 retaining bolts, if I remember rightly one of these is a long oil pump bolt and they are different sizes so use a piece of cardboard and pop them in the same positions on the cardboard noting that you are looking upwards at the balancer unit (renewal of the bolts is recommended as they are stretch type with additional angle stage tightening). Wiggle the unit slightly and it should come away - it is HEAVY!! Lower it carefully, it still has a lot of oil inside and remove from under the car. Remove circlip from oil pump drive key hole (it's very small - renew it). Drive key can be removed with a small magnet or by feeding it through from the balance shaft end. Balancer unit is in two halves. Remove strainer pipe checking gauze is clear (clean pipe and gauze if necessary and renew pipe seal). Undo retaining bolts again they may be different sizes and lift off top half leaving bottom half with balancer shafts in situ. Shafts can be lifted out from bottom half of unit and gearing checked. Replacement is usually no 2 shaft which has the drive key hole for the pump with a modified version (yours or exchange). Clean visible oil channels on both halves and inspect shell bearings of balancer unit where shafts sit. Renew shells if worn or scored. Apply thick oil or assembly lube to inside of shells and clean balance shaft journals. When replacing a shaft ensure that the flat surface of the balance weight on each shaft sit level with each other (once their gear cogs have been reintroduced) in the bottom half of the balancer unit. Apply assembly lube to balance shaft gear cogs. Fit a new upgraded drive key of the correct length with retaining circlip. Refitting is the reverse of removal noting that a special tool will be needed to retain the shafts in a specific position in the balance unit to align the drive gears and ensure they marry correctly before bolting the unit to the specific torque / angle settings. A very small amount of backlash (backward rotation of the lower and intermediate cogs) should be present after refitting the unit. You should have very slight rotational "play" for want of a better word when turning the lower gear cog against the intermediate one. This is necessary to avoid gear damage or excess wear. Too tight against each other and the gear teeth will grind. Seal sump with silicone sealant before refitting. Refit all other components removed applying correct torque settings.

CHECK: REMOVE ALL LOCKING TOOLS AND REFILL OIL!!

Rotate engine by hand a few turns to ensure free movement and no sticking of balancer unit gearing.

Reconnect battery and start up.

[waynetdi130]

Hi
Thanks for the instructions they are brilliant, that's way beyond my car diy skills, looks like i'll have to pay a garage to do that for me, thanks

[DMitch16]

First time I did it was a little daunting, didn't realise how heavy the unit was and had no second pair of hands to help. Took all my strength to hold it back up to the crank carrier with one arm and to screw the bolts in with the other after I'd replaced the balancer shaft!

[RichardSEL]

DMitch16 >> bolting the unit to the specific torque and angle settings.

Are these different for different versions of TDi? Where can these be got?
Guess if the average DIY-er hasn't got the locking tools it renders the job un-economic as compared to indies that know their stuff?

[RichardSEL]

Hi
Thanks for the instructions they are brilliant, that's way beyond my car diy skills, looks like i'll have to pay a garage to do that for me, thanks


An excellent Polish video of a complete strip down and rebuild of an oil pump assembly (but does not include removal from car) is at:
Regeneracja Napędu Pompy oleju 2.0 TDI - YouTube (http://www.youtube.com/watch?v=1y6LE8aY2mI&feature=youtu.be)
The video shows a full-on twin balancer shaft oil pump assembly unit re-condition service for exchange/resale. You don't have to clean it or strip it down into a million pieces to this detail to fit the re-manufactured balance shaft and longer key. It’s a much simpler job replacing just these parts in situ although the complete unit does have to be removed.

Have a look at this site with works based in Leamington Spa. As part of their services offered they drill out the old worn key way bore that isn't hexagonal. Then place an insert that is ten times harder chrome vanadium deeper, with a proper hexagonal bore.
http://www.motortec.biz/

[DMitch16]

I used the torque settings in the workshop manual that is part of ELSA Win the VW software which were specific to my very model and engine but also have a Haynes with them in. As the Haynes is not model specific and they only quote different torque settings for the various bolt sizes I would think they are the same for most if not all the balancer units across the B6 range.

I have seen the Polish video and also the balance shaft chain upgrade that Myturbodiesel made. Both very informative and watched before I threw myself into the job.

I paid just over half (£125) of what most balance shaft refurbishers are charging for my exchange unit and all it takes is a decent hardened helicoil to be tapped into the rebored shaft hole and a hardened 6mm key of appropriate length based on whether the reborn is stock for the 77mm key or deepened by 23mm for the 100mm key. Mine was the 77mm key refurb which will still outlive the car.