Hi folks, In a right pickle here... tried to change the cam belt on my 1990 Driver (1.6) today, and I'm lost the timing setting. Shouldn't be a problem - but I just can't reset it. Any tips please? Haynes says to align the notch in the crank pulley with the punch hole in the intermediate sprocket. I've done that. As a check of the crank position, when I do this, then refit the lower plastic cover and crank pulley, the notch in the crank pulley lines up with the mark on the lower timing belt cover, so that looks good. As a check of the intermediate shaft position, the rotor arm lines up spot-on with the notch at the back of the distributor (cap removed). Then it says to line up the mark on the back of the cam sprocket with the end of the rocker cover. But there is no such mark on the cam sprocket! There's a little punch mark on the front (which someone has previously tippexed for me), right at the outside of the sprocket - more or less on one of the teeth. So I lined that up with the point it suggested. Result: doesn't fire. Checked with a timing light, and it's firing precisely at the expected point (as the cam sprocket hole lines up with the end of the cam cover). Spoke to a VW mechanic and he said it sounds like Haynes have described the wrong engine. I should line up the cam mark with the "10" arrow on the plastic top part of the cover. Did that. Still doesn't fire. Timing light shows it's firing precisely at the expected point (cam mark at the "10" arrow). So... what am I doing wrong? In a major pickle as the MOT on my other car is out, and I need to get to work... All help much appreciated! Thanks! -Mark
When you think you're all timed up, remember that the cam turns once for every two turns of the crank. Check that No1 cylinder is at TDC, and both the valves are closed (cam lobes pointing upwards-ish) On the GTI 8v there is a line mark on the front of the cam pulley, which you can line up with the mark on the half-moon cover behind the pulley, AND there is a punched dot on the back of the pulley, which should line up with the front top edge of the head. I'd have thought the driver pulley was the same, but maybe there's a minor difference. Are you sure the pulley's on the right way round?
Thanks for the reply. Yes, the (crank) pulley is definitely on the right way round. None of the sprockets have been taken off (by me - but I suppose they may have been in the past). Yes, for every two times the crank lines up, the cam only lines up once. I can't easily check the position of the cam lobes, as the rocker cover is back on. I guess I could take it off again. How do I check the No1 cylinder is TDC? I will have another look for the markings you talk about. All I saw was a punch dot on the front of the cam pulley. Ta, Mark
Yep, just checked - there are no marks on the back of the cam sprocket, just the one "punch" mark on the front. Also, on closer inspection the mark on the plastic half-moon part is "O.T." (not "10"). I see (in an old thread) that there is apparently an "inside" and "outside" mark on the cam pulley. I can only see one. Where am I looking for the other please? Had a pretty good look and can't see anything, but maybe I'm looking in the wrong place. The only one I can find it a punch mark on the outside face of the sprocket, more-or-less in the side of one of the sprocket teeth. Wish I'd looked closer at it before I'd taken it off...
It's the first sign of madness, talking to yourself, you know... Someone at work has suggested I may have flooded it with all the messing around. Anyone have any views on that? Assuming it's as flooded as can be, how long would I expect to have to crank it before it comes to life? And to ask again... is there any way I can check the crank and cams are in TDC position before fitting the belt - is there a way of telling from the flywheel end for the crank? Any way at all for the cam? Is TDC between the exhaust and intake strokes (i.e. exhaust valve just closed, inlet just about to open, so both lobes "nearly" touching the valves) or between compression and combustion strokes (i.e. both valves far away from the valves)? Bit worried I'm never going to get this right, as I currently have no idea what the problem could be... Thanks, Mark
To clear a flooding problem, take the plugs out and turn it over for a minute. You'll see clouds of mixture if it's flooded - and don't smoke near it!! With the spark plugs still out (easier to turn it over) At TDC if you gently check down the No1 plug, you can feel the piston at the top.. the screwdriver/other implement will only go in about an inch or two. Get a 19mm 12 point socket on the crank (not cam) pulley and rock the engine back and forward a little to check it's at the top of its travel. Check that the screwdriver/ stick / other isn't jamming into the spark plug threads...Either that or put it in 5th gear and push the car back and forward. TDC on a standard cam, is inlet recently closed, exhaust opening soon. The No. 1 cam lobes should be pointing level or a bit upwards, from memory. If you're happy that the cam timing is right, try getting someone to try to start the car, while you move the dizzy a little bit by hand. Make sure you know where you started from, so you can put it back.
Thanks for the info Mike. I want to avoid touching the dizzy if I can possibly help it, as I think the last thing I need is a fourth item out of alignment. I have a timing light, so I should be able to check the ignition timing without doing that. Where is it supposed to spark while cranking? I presume it's a few degrees before TDC, so the "spot" on the cam sprocket should appear to the left of the marking on the half-moon? How much before?
OK. I have the Haynes manual, but it's wrong about the timing marks on the cam sprocket(doesn't mention the half-moon, talks about a non-existant mark on the back of the sprocket) so I don't think it's going to be a lot of use... Ta, Mark
Sounds to me like someone has put your cam pulley on backwards. I have never seen the punch mark, the wee dot on the pulley, on the outside? I am going to, have something of a competition, with myself, to see if, I can put as many commas, in a sentence, as Dunter, but, I'm not sure. Yank the rocker cover and check that the cam is at TDC when cylinder no.1 is at tdc. I suspect you have been fiddled with.
I actually meant to say "As Mike said", but I forgot. Please forgive me, I will place a Buddhist monk in a public place in Saigon and then set him on fire as a symbol of my shame. If you don't reply within ten seconds of my post I will assume you have not forgiven me.
As it happens I was doing just that as you wrote it... Here are some pictures (large, sorry, but wanted to get the detail): Showing punch mark No1 lobes No1 lobes again From gearbox end I forgot to put the half-moon thing back on until after I'd taken the first pic, but trust me that white dot (in the centre of which you can see the punch mark I'm talking about, if you show it full size) lines up with the "O.T." arrow absolutely spot on. (Crank and intermediate both set to TDC on No1, both verified in other ways.) Now this doesn't look like TDC to me. The lobe closest to the sprocket is facing almost directly down. Is anyone clever enough to tell me exactly what's wrong? Does that cam sprocket look like it's on backwards? Or is it some other weird problem. How can I accurately find TDC? Sorry for the misunderstanding - I thought Mike was talking about the crank pulley (which I have removed, therefore subject to being wrong). The crank sprocket (or any of the sprockets) could be wrong for all I know. Thanks very much! -M.
Ferkin'ell... Mahoosive Pics!! Notice how the tappets aren't both sitting up... you've got a valve open there! I think it's pull the cam-pulley off and turn it round time. I'm wondering if someone has stuck an old intermediate shaft pulley on there... I think they only have the mark on one side... To get the CAM pulley off, to try turning it around, I find it easiest if you slip a long socket extension through the hole in the pulley, and allow it to rest, on top of the rubber gasket or other soft material to protect the head itself, and use that to lock the pulley in place. (you're still using a cork rocker gasket, bin it and get a rubber one - change the studs to plain ones or it won't sit right...) If you rely on the cambelt tension, you'll probably find it just skips teeth, rather than loosens the bolt.
Did you change the tensioner... doesn't look new in that pic (tsk tsk!) While you're in there... wanna buy a GTI cam to make it go faster - you can have one with a proper pulley on it!
thats quite a few teeth out my friend as mike said you defo got a valve open the lobes generaly point up slightly at an angle
