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Cambelt on SDI. What a horrid job!

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I have worked on many cars and I have to say that the Lupo SDI has got to be up there as one of the most difficult CAM belt changes I have ever done. I now get why on Lupo ads, they say "cam belt changed". Yup. :rant: I think dropping the engine/box out might be quicker next time.

I've now been battling for about two hours. Everything is off except the accessory belt pulley (on the crank), which is refusing to come off.

Am I right in saying you only need to remove the 4 bolts? Don't touch the middle one?

I don't want to use a puller (plus I don't think there's enough room to get in there anyway), because it's made of alloy and I'd probably bend it.

I have a feeling that after 12 years from new, neither belt has ever been changed. The 'fan' belt almost crumbled in my fingers once it was off (easy job).

While everything is out, I might do the water pump at the same time, as the bearings have a slight amount of play. Peace of mind I guess down the line.

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It is a nasty job even when it all comes apart.

I love doing TDI belt changes, I could happily do them all day.

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What mileage/age of that belt?

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You have to take the crank pulley off (4 allen cap screws) to lock the crankshaft. I don't see any locking tools! Your belt wasn't far away from failure.

RAB

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Surely as long as you don't disturb the gears you should be ok, just mark up the gears and new belt and make sure it goes back as it came off.

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Nought wrong with using paint marks when the old belt is still on... So long as everything lines up again after a few hand turns of the engine, all is good. Never failed me yet.

Yeah this belt i'd say it is/was the original from new.... 12 years later! 60k miles. But I must say that it is nice to work on a factory original engine where there are no bodge jobs. All bolts correctly torqued, nice and clean threads and everything lining up beautifully. It says a lot for longevity of OEM parts.

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You have to take the crank pulley off (4 allen cap screws) to lock the crankshaft. I don't see any locking tools! Your belt wasn't far away from failure.

RAB

I made a locking tool... Not visible. Flat bar with two bolts sticking out, spaced apart by the bolt centres. I don't think it's possible to undo those 4 bolts (high torque) without locking the crank. Edited by mk2

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Can't beat the old tip ex pen.

at 236k and the fact that it's quickly losing power I'm going to play the belt lottery forever.

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Can't beat the old tip ex pen.

at 236k and the fact that it's quickly losing power I'm going to play the belt lottery forever.

236k on the original belt?!??! What!?! no way.

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I doubt it is the original belt, but I have no idea when it was last changed.

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Can't beat the old tip ex pen.

at 236k and the fact that it's quickly losing power I'm going to play the belt lottery forever.

I know someone, although I'm not going to name him, on this forum who played belt lottery with a Lupo 3L, one of the very few in the UK. If I remember rightly, it hadn't been changed since the first interval and the car was on something like 140,000 miles (230kM).

Although I won't name him, I know for a fact Rich that you don't have very much time for him.

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I know someone, although I'm not going to name him, on this forum who played belt lottery with a Lupo 3L, one of the very few in the UK. If I remember rightly, it hadn't been changed since the first interval and the car was on something like 140,000 miles (230kM).

Although I won't name him, I know for a fact Rich that you don't have very much time for him.

If that was an original RHD 3L, that is not too bright.... They are worth a lot now. I wanted one before I bought the SDI, but then realised that the only choice now is a LHD import. No thanks. People who risk a cam belt either have money to burn or.... I won't insult anyone today!

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If that was an original RHD 3L, that is not too bright.... They are worth a lot now. I wanted one before I bought the SDI, but then realised that the only choice now is a LHD import. No thanks. People who risk a cam belt either have money to burn or.... I won't insult anyone today!

There's no such thing as a RHD 3L mate. All are imports from Europe, so they're almost entirely LHD. It is possible to convert them though. I spoke to a couple of VW technicians who told me it was theoretically doable by recycling some parts from a TDi. Plus all the stuff like dash and what not. On paper it was possible. They also said it wouldn't be unreasonable to put a 1.2 TDi in a 1.4 TDi but I assume there's gearbox issues there.

To be honest, this guy might have been a bit of both.... He was certainly the second.

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I assume you mean Paz ?

I'm going to build my final lupo next year, I'm going to create the RHD manual 3l capable of 150 mpg.

Then I'm going to sell it.

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why use a manual gearbox? Tiptronic outperforms manual in the MPG department, no?

Tiptronic aren't as unreliable as people believe either. A limited understanding of them is enough to keep one running fairly problem free.

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I much prefer a manual.

Simple as.

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I much prefer a manual.

Simple as.

good answer to be fair.

I'm very keen to see where you go with this. I've hypothesized for a while whether finding a TDI with a ****ed engine and dropping a 1.2 in would be feasible.

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why use a manual gearbox? Tiptronic outperforms manual in the MPG department, no?

Tiptronic aren't as unreliable as people believe either. A limited understanding of them is enough to keep one running fairly problem free.

I'm not expert but tiptronic is still an auto isn't it with torque converter. I thought the 3l was a auto manual sort of thing.

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I'm not expert but tiptronic is still an auto isn't it with torque converter. I thought the 3l was a auto manual sort of thing.

didn't the 3L come with Tiptronic? An early incarnation of DSG?

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I'm not expert but tiptronic is still an auto isn't it with torque converter. I thought the 3l was a auto manual sort of thing.

Yeah, TIPtronic is a 100% automatic gearbox. The only thing they've done is changed the way they shift- which is down to a different program in the gearbox controller. It is possible to replicate tiptronic and paddleshifting on an 096 or 01M box. I've done it. I have a couple of 096s knocking around for a new project (one's off a corrado VR6 and the other from a 4 cyl 2L). I'm going to combine the geartrain from the 6 with the casting from the 4 pot to run a PDI with paddleshift. No idea when the project will start, but I have all the bits ready to go....

The only difference between the auto box program and the TIPtronic is the shift modulation control. For a hard shift, you want the clutches to engage suddenly (like dumping the clutch). Soft is the opposite. It's all controlled by a PWM signal that varies the current in a control solenoid inside the valve block. This is turn varies the 'shift pressure'. If there is high shift pressure, the little pistons move really quickly (or 'pop') clamping the clutches together quickly, resulting in a hard shift. The old way of doing it was with a 'modulator' which was controlled by vacuum on a petrol engine. High vacuum means slight throttle, which in turn means the driver is not gunning it, so the shift needs to be gentle. It's all common sense stuff when you think about it.

DSG and Auto can result in equal powertrain loss, depending on how they are configured. The biggest loss in an Auto is with the running pump, but that can be tweaked to be efficient once in lockup. A lock up torque convertor transmits all the power straight through. In a DSG, the loss is from all the bearings and shafts slushing around with the oil. There are a lot more shafts and gears moving, resulting in more friction.

A small manual box is still the most efficient when driven correctly (The Smart car- with computer controlled gear changes on a manual!).

Nice pic of a Tiptronic:

2014_audi_rs6_avant_89_1024x768.jpg

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Surely as long as you don't disturb the gears you should be ok, just mark up the gears and new belt and make sure it goes back as it came off.

You need two locking tools, one for the crank and one for the camshaft. When you tension the belt, both must still be locked with the camshaft sprocket (only) moving. Do you think that you can do all this with just marker pens? Impossible, at least to do it accurately. Once this is all done you have to check that you can still lock both, with the new belt installed.

You can check the accuracy of your installation with VCDS here: http://www.a2oc.net/forum/showthread.php?25921-Timing-for-1-2-TDI-PD

Frankly, to do this without tools costing about £20 is a really stupid (and false) economy!

RAB

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Jeez, sorry dad...

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You need two locking tools, one for the crank and one for the camshaft. When you tension the belt, both must still be locked with the camshaft sprocket (only) moving. Do you think that you can do all this with just marker pens?

You don't 'need' locking tools, but they are handy. The difficult bit is not making sure the timing relationship is correct (you can simply count belt teeth if you must...), but undoing and tightening the hex bolts that hold the pulleys on. That's when I usually reach for a locking tool.

The timing relationship between crank, diesel pump and cam belt is what is critical. As RAB says, get that wrong and it's game over. The thing I've always noticed when you use a cam protractor to measure belt stretch/block expansion is how much the timing varies by on a regular engine. If you measure the cam pulley angle on a block on a freezing day (about 0c) and then on a hot engine, it can vary by as much as half a tooth (first lock crank at 0 TDC). I think that is why VW introduced those spring loaded cam belt tensioners (which also fail!!!). They were trying to maintain belt tension by sacrificing timing. On older mk1 and 2s that really basic tensioner pulley never ever failed. One bolt, adjust til its about right (half a twist on the belt), tighten. Job done. Easy... No messing about trying to line up tensioner marks which move as soon as the engine cools down or heats up.... Mad world.

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