New 5 cyl Jetta V uses a Timing Chain !

[Strack]

FYI- The new 5 cyl Jetta V uses a timing chain instead of a belt which should last the life of the engine. This is a big plus in reducing operating costs in the long run. I wonder if we will ever realize a true cost savings with the tdi? Between higher initial purchase price, timing belts, MAF replacements, it may be cheaper to buy a new gasser?

 

[fastvicar]

Bite your tongue!

My father's MB E300 TD had a timing chain, too. They recommend replacement at 120,000mi. They aren't cheap, either. If only we could have gear-driven valvetrain like the Touareg

 

[Strack]

I'll take a chain driven cam over a belt drive any day including today. This is a quite an accomplishment for VW since the 5 cyl is of a twin cam configuration. In the end, who knows how long the chain will last, but smart money should double down on this one.

 

[oilhammer]

The VR5 has been around a while, it is built off the VR6 arrangement. And no, the chains don't last forever. And there are several of them. And the engine and/or transmission needs to be REMOVED from the car. If you plan on buying a TDI today and driving it 500k miles, you will have spent far less time and money on timing belts than you would on just ONE chain replacement on the VR5. My sister's '96 12V VR6's chain is making noise at 110k miles. And that is after Mobil Synthetic every 5k since new, and it is getting so sloppy that it throws a cam sensor sync error code about every couple months.

Belts are better in the long run, no doubt about it. Chains for an OHC arrangement are complex, noisy, messy, heavy, expensive. Chain replacement sometimes exceeds the value of the car. I could do fifty TDI belts inthe time it takes to do just ONE on a VW VRx engine. And for about 1/10th the cost

If you saw the nightmare arrangment of timing chain madness on the flywheel end of the 4 valve head VRx engine you'd wish you had a simple belt!

 

[Strack]

according to VW's new jetta V brochure, they are using chain driven cams , "so there's one thing that requires less maintenance for the life of the vehicle".

Toyota switched to a timing chain in the Camry a few years ago for the same reason..

i think this may really be a positive move, of course as always, time will tell.

 

[oilhammer]

Strack, did you even read my above post????

 

[Strack]

yes, i hear what your saying, but this 5 cyl is new. let's look at the design & service interval requirements before jumping to a conclusion that it will be problematic or costly. VW is going this route to reduce maintenence & operating costs. let's see how this new configurtion unfolds before it's slammed to death on the net. perhaps even vw realizes that their $850.00 timing belt replacements will force owners to consider other manufactures products when choosing a new vehicle. i'm remaining optomistic, that's all... :->

 

[oilhammer]

OK, so you DIDN'T read my post. The VR5 engine, in both 2.3L and 2.5L trim, has been around now for about 8 years. This is a carryover engine...it is NOT new, just new to the US. It uses the EXACT same timing chain arrangement as the VR6, which we have had in 24 valve trim for a few years, and have had in 12 valve trim since the early '90s. So, any issues that those engines have had this "new" 5 cylinder will have as well. Follow me? It is not a new engine, it is an old engine in a new car that is offered for the first time on our shores.

My reasoning stands: if you plan on driving a car for a very long time, a belt driven OHC arrangement makes more sense. If you drive a car to 150k miles and toss it, then a chain is just fine so long as you don't mind the other cons with a chain setup (noise, weight, cost, etc.).

Fact is, timing chains, especially long ones on an OHC engine, are by no means "lifetime maintenance free items" just because it has no mention in the maintenance booklet in the owner's manual. They do wear out, and they are frightfully expensive to replace. The the VR5/6 engines, especially the 4-valve-per-cylinder variety, have an extrememly complex convoluted albatross of a timing chain arrangement using multiple chains, an intermediate shaft, several guides, tensioners, rollers, etc. Plus it is mounted on the flywheel end of the engine!

 

[Muggins]

I'm convinced, Oilhammer. So, why not go gear drive, besides increased NVH?

 

[GoFaster]

Heads up, oilhammer ... The 5-cyl in the new Jetta is NOT the old VR5 engine. It is a completely new in-line 5. Repeat, it is NOT the old 2.3 V5 which was a VR6 with a cylinder knocked off - the cylinders on this new one are in a straight line.

However, it does share the design element of placing the timing chain at the rear of the engine behind the flywheel in the worst possible location, and it is a double-chain arrangement. I dunno why they did it this way when they could have done it the simpler way that everyone else uses ...

I put about 300,000 km on a Toyota truck, and never had to touch the timing chain in the 22R engine, and it was still fine when I sold the truck.

Gear drive is super expensive. The V10 TDI uses it, and the new R5 inline-5 PD TDI which is basically half of the V10 also uses that.

 

[oilhammer]

Ah, yes, I stand corrected

on the cylinder arrangement, but my reasoning still stands on the timing chain vs. belt talk. A new engine indeed, but we'll have to see its merit proved out. Although making only 150hp from 2.5L is pretty sad, if you ask me. Heck, the PD 2.0L TDI is just a slight tweak away from that and it has one less 500cc cylinder!

I've replaced oodles of 20R, 22R, and 22RE timing chains...many don't make it as long as yours, and I'm positive there was some signifigant wear at 300k km. Many of those slapped around so bad in the timing case they wore holes through to the water passages to the water pump and caused coolant/oil mix...with of course catastrophic results. I've already seen rattling chains on the 16v replacement for the 22RE in the Tacoma! But that is a really strong engine.

 

[vwsport]

The reason for the vr6/vr5 timing chains issues is because of the rail / plastic guide. I assume in the years they have come up with a new design for that, or use different materal. I will put some money down that these new I5's will do better than the vr6's. I get the joy of doing the chain guides on my vr6 soon

Dan

 

[TDIMeister]

Glass-reinforced Nylon or PA (Polyamide) 6/6 is the almost universally-used polymer material for chain guides.

 

[GoFaster]

So what's the difference between the ones that last, and the ones that wear out?

I know the 22R had a reputation for wearing out the guides, although usually not until the truck was pretty tired. I never had any trouble with mine, but I heard a noisy one with about 300,000 miles on it in the USA; owner knew the guides were shot, but the truck was a rustbucket (so was mine!) so he was just driving it until it blew up.

Early VR6's got a BAD reputation for chain guides (among many other things). I haven't heard so much about the later ones.