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JoeyEunos

Timing Belt Kits Inc Deflection Pulley?

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The time is looming to change the timing belt/water pump etc, I'm feeling brave so I'm going to have a a crack at it myself this time round ;)

Having looked about in the usual places (GSF,EuroCarParts,CarParts4Less etc) I've bee struck with an anomaly... The kits I can find come with an 'Including deflection pulley, or 'Not including deflection pulley' option, those including the pulley costing and extra £30 or so.

My question is really simple, I'm hoping @Rich, @Skezza, @Hazy or one of the other site SDI guru's can help me with this, it's probably a reflection of pure ignorance on my part but I've never heard mention of a 'Deflection pulley' <_< Are they simply referring to the idler pulley that sits at the top/front of the block?

Also, and probably the most important question, would you consider it to be good practice or necessary to opt for the more expensive kit and replace this mysterious 'deflection pulley' too whilst I'm in there?

As always, thanks in advance to anyone who can chime in with advice/suggestions or musings on the subject.

 

 

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Yeah, I change them... They do a lot of RPMs. Like 5x what your engine is running.

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I'm in the middle of doing a complete SDI cam belt how to... Lots of tips and tricks to make it easy. Probably by next WE.

Edited by mk2
typo
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I always changed all the pulleys of  timing belt kit.

Elements.jpg

You can also change optionally the ribbet belt, ribbet belt tensioner pulley, alternator pulley and coolant pump. It depends on their condition and requires an initial evaluation. I never replaced the coolant pump when I changed the timing belt kit (I replaced it once from error when the car had 124,000 miles, currently it have 205,000 miles). I replaced  the ribbet belt tensioner pulley twice (one of them by mistake of course:)) and the alternator pulley twice (one was the real cause of the two errors:D)

It might be necessary to replace the toothed belt cover, the lower part

toothed belt cover.jpg

When I changed the last time the distribution, the cover looked quite bad ( It was deformed and scuffed by the sprocket ).

I attached some documents and do not forget: after changing timing belt kit is mandatory to do dynamically checking and adjusting commencement of injection. For this it is necessary a vagcom or a vcds.

 

 

Removing, installing and tensioning toothed belt.pdf

Checking semi-automatic toothed belt tensioning roller.pdf

Dynamically checking and adjusting commencement of injection.pdf

Removing and installing ribbed belt.pdf

Removing and installing ribbed belt1.pdf

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Never seen a deflection roller before, that is some real shitty design if they feel the need to include one.

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Thanks for the help chaps :)

 @mk2 and @lupo 1.7sdi I'm not really sure why I didn't include you in my list of site SDI gurus in the OP,  you guys escaped my mind so muchas gracias for chiming in on this one! There are so many of us running and maintaining SDI's on here I recon it might be about time someone created an SDI-centric sub section of the forum for us all to lurk and post in but that's a topic for another thread :D

@mk2 I'm glad to hear that you opt for the more comprehensive kit, seems like it will provide peace of mind for the sake of an extra £20/£30, also, great news about your proposed 'how to' on SDI timing belt replacement, now that would be awesome.

@lupo 1.7sdi As usual, a really comprehensive post, cheers, althought frustratingly the PDF links you've posted don't work for me... Do I need to copy and paste them into the address bar of another browser? FWIW I'll be doing the coolant/water pump whilst there, it seems counter intuitive not to ^_^ I hadn't counted on checking the injection with vagcom or a vcds, as it stands my diagnostic equipment is limited to a cheap Chinese OBDII scanner so thanks for the heads up on that. I'll get on Ebay and have alook at rectifying that ;)

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They are not links, they are attached documents to post (in pdf format, to read them need to be logged in and you must have Adobe Acrobat installed on your computer).

But if you can not read them nevertheless, I have converted to doc.

Removing, installing and tensioning toothed belt.doc

Checking semi-automatic toothed belt tensioning roller.doc

Dynamically checking and adjusting commencement of injection.doc

Removing and installing ribbed belt..doc

Removing and installing ribbed belt1.doc

To check the commencement of injection you do not need an VCDS too recent, a 409.1 vagcom is sufficient (of course It must have full functionality, not with shareware program)

Edited by lupo 1.7sdi

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@mk2

I'll answer here because It was a bit offtopic on the topic where you asked: 

Yes, the ECU compensate a wrong timing adjusted, but within certain limits. I'll explain a little using my own engine.

My timing is  a little late.....a bit more:D. We can see this in Basic settings, group 000, the second display zone (this is my actual timing).

basic set 000.jpg

This is not good. At this engine (AKU) this numerical value must be  like in next picture

aku avasn.JPG

but this is not a tragedy because the ECU working hard and working hard and we can see the results in Measuring blocks, group 000, the second display zone

measuring blocks 000.jpg

it looks like the picture above ;)

Yet no matter how much it is deregulated the timing and this can be seen in Measuring blocks 004 group. In this group numerical value in display zone 3  should be almost equal to the numerical value in display zone 2 and in this time the numerica value in display zone 4 must be in the middle of the range.

My engine  meets these conditions and did not beat my head with additional adjustments

004 group.jpg

It is important to note that the starting ECU does not influence the timing so it is very important for a good starting the numerical value of timing in Basic settings 000 group.

Fortunately my car starts perfectly with timing in all conditions as it is set nowB)

Last winter started to -20 celsius (-4 Fahrenheit) without glow plugs, hard but it started.

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OK,I understand. :) Good explanation.

So how does the ECU change the injection stroke? Is there a mechanism inside the pump to make the diesel pressure stroke start earlier or later? I know the ECU bases all its timing on the crank sensor, so if the injector stroke sensor signal is too early or late compared with the crank sensor signal, the ECU can pick that up. What I don't get is how it can adjust it. On PDI engines, the pump injector has a solenoid that is controlled by the ECU, so the injection duration can be controlled. But not the start point, which is done by the cam stroke. A bit like how tsi system works on petrol engines... It can shut off the injection stroke, but not open it, as the pressure is too high.

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Aha! Thanks. I'll investigate.... :) Just like you say, the ECU can control the timing so the injection pump position is not super critical. That means either my pump timing is so far out or there's something seriously wrong with my engine! I'll need to dig out my vagcom lead...

Compared with my other SDI, this engine is really noisy and 'knocky'. Could just be that the big end bearings are worn, but its only done 90k miles. So just run in. Hmmmm.

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where does the fuel temperature get measured???

My measuring blocks say about the same as yours, so everything must be ok (I turned the injection pump back to original position).

I double checked all the belt timing positions and pulleys. Perfect.

Everything is within the normal injection zone.

So why is my engine sounding really bad...? Very knocky.

 

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In group 007

3.jpg

For a knocky engine can be  both management causes and mechanical condition of engine.

To determne the management causes the following is needed:

  • if there are error codes
  • Some printscreen (or pics), as a in the example above, to the following groups: 000, 001, 004, 007, 013, 015

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No error codes..
I'll try and do some screen grabs.

I think it may just be a worn engine. I'm used to my other lupo that purrs it is so smooth...

This engine has no smoke. No oil consumption. Good power. Easy starting. Lots of noise. Only done 200 miles so far. Standard engine. No egr. Gas flowed induction system. Oil fume breather bypass system.

I haven't checked the cam pulley to cam shaft alignment yet- I'll need to take the rocker cover off...

I just had a thought- what symptoms do you get if the cat is blocked?

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Intake flap is on or off?

How the  flowed induction system looks? A pics, or a link because I am very curious how this system looks  and how effective it is.

I don't think the cat is blocked. If it is blocked...no power. How is the idle fuel consumption (group 015, the third display field)

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I'll do some more measurements in a few days...

More questions....!

Where is the fuel temperature measured?

From looking at the injection timing graph, I get the impression that as the fuel heats up, the start of the pulse is delayed. Does that mean that when the diesel is really cold, the start of the diesel pulse is more advanced?

Is is possible to change the injection timing in the ECU, or maybe I can trick it by messing with the fuel temperature reading....

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On 09/11/2016 at 9:01 PM, lupo 1.7sdi said:

How the  flowed induction system looks? A pics, or a link because I am very curious how this system looks  and how effective it is.

induction manifold off

clean

machine up some aluminium slugs to ram into the EGR inlet ducts

press them hard into the induction holes (interference fit)

machine off excess material

smooth off

clean

refit ram tubes or trumpets and seal with very high temp silicone

smooth silicone around join of ram rube and ram tube mounting, no stupid gaps- so airflow stays nice and laminar

allow to cure

fit to engine

drill out intake flap (add 3x 10mm holes)

drive car... :)

pics:

141scuc.jpg

f1hch0.jpg

uxxmh.jpg

zsq1qq.jpg

25kmnad.jpg

21l966c.jpg

 

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Finally got some screen grabs of VCDSlite and VAGCOM... Can't make much sense of either numbers TBH.

I'd like to know how to log the injection start  points when cranking.

I can get the numbers when stopped- like it says 5 degrees expected; actual degrees '0'- obviously.

Then as soon as I start and idle, the software resets (as it loses the comm link for a moment), then shows me the following:

1zqsdjp.jpg

I'm guessing that the duty cycle number is the pulse that switches on the injection pump timing valve N108. Am I right in guessing that the higher the number, the further out the static timing is? (as in the position of the injection pump is slightly out) If the duty cycle number is 50%, that is perfect, or is ideal 0%????? I understand whats going on, but can't make much sense of the numbers.

13z0suw.jpg

I have discovered some wierd quirk of the SDI however. If you rev a warm engine up to say 3000revs pull your foot off the throttle pedal and at the same time momentarily cut ignition, then when i turn key back on at about 2000revs, the ECU resets and fires loads of fuel  in (at the wrong time) knocking badly until about half a second later it resumes 'normal play'. Is that a sysmptom that my static timing is too advanced??? Just thinking aloud here....  :)

 

Edited by mk2

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Thanks for pics, very interesting. Currently I canceled the EGR valve and intake flap by canceling the vacuum and I feel better torque at low revs, but I see that it can be better:lol:.

Your screen grabs looks good, but  let's take them one by one:

  • gr. 001: the amount injected at idle is a bit high ---> the consumption at idle could be a bit high (I have 0.3l/hour--->gr 015),  low consumption in motion (my consumption) and the car can be a bit lazy. My engine has 2,4mg/str at 900C. It can be adjusted small limits with this method  or in larger limits with hammer mod 
  • gr 004: Ok, but is interesting to know which is the value in Basic settings, 000 group, the second field.

You can log any kind of parameters (Push Log--->Browse-->Start--->Done,close) at idle or walking ( very useful in this situation because you can record parameters without having to keep an eye on laptop ), but at start if the battery it is not in good condition  the software will loses the communication with ECU due to lower voltage, so you need an additional source of power (another car)

I attached some information about measuring blocks and how to test the N108

Observation:
1.It is more useful to attach logs to the post

2. I think we need a separate topic for the diagnosis of Lupo/Arosa diesel engines

 

measuring blocks.pdf

Checking injection timing control range.pdf

Edited by lupo 1.7sdi

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Yeah I think the injection quantity at idle is directly related to temperature, as the priority program is idle speed. My engine was not at 90. With any diesel engine speed is directly affected by fuel quantity and nothing else! So simple... But the timing has to be right.

I can't open measuring blocks 000. Vcds will not let me with the shareware software. Have you paid for vagcom? US$250!

I think we need a new thread. Right   :)

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