1.4 TDI PD Balancing Shaft Chain Replacement

[rone18]

Background

 

The 1.4L TDI PD engine is designed with a balancing shaft mounted on a ladder-type frame underneath the crankshaft. The purpose of this shaft is to counteract uneven oscillations that are induced as the engine runs. The balancing shaft is driven at crankshaft speed and in the opposite direction by a chain which additionally drives the oil pump. Due to high loads that are placed on this assembly it is susceptible to wear, which can result in the drive chain snapping or losing tension - in either case causing serious engine damage.

 

I planned to keep my Fabia long term and so decided to change the following components at 138,000 miles as a precaution:

• Balancing shaft drive chain and tensioner
• Balancing shaft drive sprocket
• Balancing shaft chain idler sprocket
• Oil pump sprocket

Additionally, whilst undertaking this work the following was also replaced since they require removal to access the balancing shaft components:

• Toothed belt and water pump
• Front crankshaft seal
• Engine oil and filter

 

I bought the car in 2017 with 103,000 miles – it had full Skoda service history and was serviced every 10,000 miles. Since then I have maintained the car, servicing every 8,500 miles with only 507.00 approved oil and MANN/Mahle filters.

 

This work was undertaken as a DIY project on a driveway with axle stands, it took 3 days of gentle work however could probably be done in a weekend.

 

Findings

 

Upon removal of the balancing shaft drive components, it was evident that the tensioner was severely worn and nearing total failure. The chain had been rubbing against the engine block [see images] and the sump, I suspect that this is due to the extreme extension of the tensioner. The pads on the tensioner were almost completely worn [see images], with one of the pads also demonstrating very uneven wear. The drive gears appeared in good condition. It’s difficult to comment on the chain wear, however, it certainly had more visible wear than the new chain.

 

(Above) Old balancing shaft drive components that were replaced.

(Above) Balancing shaft sprocket

(Above) Idler sprocket

(Above) The top of this pad was very close to being completely worn through.

 

(Above) Old balancing shaft drive components removed from the engine, the scoring from the chain is visible.

(Above) Scoring on the engine block where the chain had been rubbing. Similar scoring was also visible in the oil sump.

 

Having had the new drive components fitted for a few days the engine is now much smoother and rattles less at idle and under partial load. It’s impossible to say how much longer the engine would have continued with the old components but I am very pleased that I decided to change them.

 

(Above) New drive gear fitted.

 

Stuff Needed

 

If you plan to do this job you absolutely must buy access to erWin and download the Skoda repair manual for this engine. This is how I completed this repair and it was an invaluable resource. To give an idea of the scale of this job and the prices involved I have outline parts required and the specialist VW tools needed.

 

Parts List

• SWAG 99 13 2266 – Oil pump drive chain set, £106.87
• Corteco 20026412B – Crankshaft oil seal with transition sleeve, £7.87
• Corteco EVO300 – Sealing substance for sump and crankshaft seal housing, £3.08
• SKF VKMC 01250-2 – Toothed belt and water pump kit inc. tensioner and idler roller studs, £83.74
• 3L G13 coolant concentrated – approx. £20 from VW dealer
• 5L de-ionised water – approx. £3
• 4L Castrol Edge 5W-30 LL 507.00 engine oil, £25 (Note that the engine needed an additional 500ml to fill since the sump and baffle had been removed and cleaned.)
• Mahle OX 188D – Oil filter, £5.91

 

• N 10261310 - Engine mount to body nut, 1x £0.81
• N 10286205 – Engine mount to engine bracket, 3x £2.84
• N 10315605 – Oil pump sprocket screw, 1x £2.39
• N 10315605 – Balancing shaft mass and sprocket screw, 1x £2.48
• N 10700201 – Chain tensioner to engine block screws, 3x £0.46
• WHT004573 – Crankshaft sprocket screw, 1x £6.47

 

Specialist Tools

• MP 1-301 – Crankshaft locking pin
•  T 10264 – Timing belt tensioner locking pin
• T 10050 – Crankshaft arrester

The three above tools can be bought in a generic TDI timing tool kit from eBay for around £10. I used one of these and it worked perfectly.

• T 30004 – Crankshaft counterhold tool for removing crankshaft pulley bolt. Generic versions of these can be sourced from eBay for around £25.
• T 10053 – Crankshaft seal installation tool. This tool is very expensive, what I did was buy a seal with the internal transition sleeve and then use a shampoo lid with a 16mm hole as the pusher. [see images] The lid is from a large shampoo/bubble bath from Wilko.

 

(Above) DIY crankshaft oil seal tool. The outer pusher is a shampoo lid with a 16mm hole drilled though its centre.

 

Summary

 

This was intended to be for information and not a how-to guide. Hopefully this information is useful for other owners of this engine. If you have a higher mileage 1.4 TDI and it is due a cambelt soon then this is something to consider for replacement.

Edited 31 July, 2019 by rone18
Added images and captions to post body.

[Cheapas]

Hi thanks for the info. Have recently bought a Fabia 1.4 TDI Greenline 2008 with 110,000 miles so maybe will have to consider this also. Would be interested to know if any 1.4's have reached say 200,000 miles without this work and if there are any tell tale signs/noises of impending trouble. Read somewhere else that these engines are supposedly bullet proof! Thanks again....

[rone18]

23 hours ago, Cheapas said:

Hi thanks for the info. Have recently bought a Fabia 1.4 TDI Greenline 2008 with 110,000 miles so maybe will have to consider this also. Would be interested to know if any 1.4's have reached say 200,000 miles without this work and if there are any tell tale signs/noises of impending trouble. Read somewhere else that these engines are supposedly bullet proof! Thanks again....

 

I suppose every engine has its faults, the 1.4 TDI seems to have very few of them and is a robust engine - I've had no problems with mine as of yet. I wasn't expecting the chain and tensioner to be showing this level of wear given how well it's been looked after, but then there is no real info regarding what affects the rate of wear of the balance shaft drive. I had assumed oil changes and the quality of the oil used could be the only factor determining this, however my car would appear to contradict this. (Not that a sample size of 1 car indicates anything at all!) This engine was introduced in 1999 and was available in the UK until 2010, the design of the balancing shaft drive wasn't revisited and is almost identical in the 1.2L CR unit, so trusting the engine designers there's nothing to worry about. There's so many of these cars out there and given it's difficult to find information on failures of the balancing shaft drive indicates that it is rare.

 

A good source of info on this and the 1.4 TDI in general is A2OC - plenty of 1.4 TDIs on there with over 200k, also plenty of reports about this drive chain:

• TDi Owners MUST read please
• 1.4 TDi oil pump / balance shaft chain and chain tensioner replacement.
• Balancer shaft chain guides and sprockets
• Help required please ! Failed to get to 200k club ?
• Failed oil pump and aftermath

To contradict the above posts there's a fair few around and over 300,000 miles: The quest for the highest mileage A2 and the 200K Club