JoeyEunos Posted November 6, 2016 Report Share Posted November 6, 2016 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. Quote Link to comment Share on other sites More sharing options...
mk2 Posted November 6, 2016 Report Share Posted November 6, 2016 Yeah, I change them... They do a lot of RPMs. Like 5x what your engine is running. Quote Link to comment Share on other sites More sharing options...
mk2 Posted November 6, 2016 Report Share Posted November 6, 2016 (edited) 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 November 6, 2016 by mk2 typo 1 Quote Link to comment Share on other sites More sharing options...
lupo 1.7sdi Posted November 6, 2016 Report Share Posted November 6, 2016 I always changed all the pulleys of timing belt kit. 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) It might be necessary to replace the toothed belt cover, the lower part 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 1 Quote Link to comment Share on other sites More sharing options...
Sausage Posted November 7, 2016 Report Share Posted November 7, 2016 Never seen a deflection roller before, that is some real shitty design if they feel the need to include one. Quote Link to comment Share on other sites More sharing options...
JoeyEunos Posted November 7, 2016 Author Report Share Posted November 7, 2016 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 @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 Quote Link to comment Share on other sites More sharing options...
lupo 1.7sdi Posted November 7, 2016 Report Share Posted November 7, 2016 (edited) 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 November 7, 2016 by lupo 1.7sdi Quote Link to comment Share on other sites More sharing options...
lupo 1.7sdi Posted November 8, 2016 Report Share Posted November 8, 2016 @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. We can see this in Basic settings, group 000, the second display zone (this is my actual timing). This is not good. At this engine (AKU) this numerical value must be like in next picture 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 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 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 now Last winter started to -20 celsius (-4 Fahrenheit) without glow plugs, hard but it started. Quote Link to comment Share on other sites More sharing options...
mk2 Posted November 8, 2016 Report Share Posted November 8, 2016 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. Quote Link to comment Share on other sites More sharing options...
lupo 1.7sdi Posted November 8, 2016 Report Share Posted November 8, 2016 Yes, it is a mechanism in the injection pump. It is known as N108 valve (no. 17 in below picture) Quote Link to comment Share on other sites More sharing options...
mk2 Posted November 9, 2016 Report Share Posted November 9, 2016 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. Quote Link to comment Share on other sites More sharing options...
mk2 Posted November 9, 2016 Report Share Posted November 9, 2016 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. Quote Link to comment Share on other sites More sharing options...
lupo 1.7sdi Posted November 9, 2016 Report Share Posted November 9, 2016 In group 007 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 Quote Link to comment Share on other sites More sharing options...
mk2 Posted November 9, 2016 Report Share Posted November 9, 2016 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? Quote Link to comment Share on other sites More sharing options...
lupo 1.7sdi Posted November 9, 2016 Report Share Posted November 9, 2016 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) Quote Link to comment Share on other sites More sharing options...
mk2 Posted November 10, 2016 Report Share Posted November 10, 2016 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.... Quote Link to comment Share on other sites More sharing options...
lupo 1.7sdi Posted November 10, 2016 Report Share Posted November 10, 2016 5 hours ago, mk2 said: Where is the fuel temperature measured? There is a sensor in the injection pump Quote Link to comment Share on other sites More sharing options...
mk2 Posted November 17, 2016 Report Share Posted November 17, 2016 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: Quote Link to comment Share on other sites More sharing options...
mk2 Posted November 29, 2016 Report Share Posted November 29, 2016 (edited) 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: 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. 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 December 2, 2016 by mk2 Quote Link to comment Share on other sites More sharing options...
lupo 1.7sdi Posted December 2, 2016 Report Share Posted December 2, 2016 (edited) 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. 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 December 2, 2016 by lupo 1.7sdi Quote Link to comment Share on other sites More sharing options...
mk2 Posted December 2, 2016 Report Share Posted December 2, 2016 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 Quote Link to comment Share on other sites More sharing options...
Sarahs Lupo Posted November 6, 2019 Report Share Posted November 6, 2019 interesting read. must get some software to read mine Quote Link to comment Share on other sites More sharing options...
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