AEL cam timing - hard cold starts after timing belt change

Newbie Joined: Aug 15, 2013 Posts: 4

Hi guys, new to posting here but I've been reading quite a bit in the last few months since owning my 1996 A6 TDI, imported to Canada from Czechoslovakia. Having an imported car is a bit of a bugger, but not too bad. Just have to be patient waiting for the diesel parts Smile

I had a 1.9l TDI Beetle, which I then transplanted the ALH into a 96 S6 (crank then broke), and I also have a 87 4000 (or 80) with an AAN from a 92-97 S4/S6.

So anyway, about a month ago the timing belt tensioner died while my wife was driving the car. And she drove home! Ugh, I thought for sure my valves would be toast. But it turned out almost identically as the "timing belt woes" thread (linky here)

So I don't have a Bentley or any of the special tools and can't find them anywhere. I had the valve cover off to verify cyl1 lobes up, but couldn't lock the cam. I verified timing visually several times and rotated the engine twice over to ensure no contact, but I have a feeling the cam must have rotated just slightly. I have my timing set with VCDS/VAGCOM and it is slightly advanced. About 48-52. I had it set further advanced (didn't have vacgom at the time of the belt swap) so it would start fine, but obviously when I hooked up vagcom and saw 70* of timing I backed it off. Car seems to get much better fuel economy but starts are bad. Once started/warmed slightly it starts great, but after sitting it cranks too long. It's summer so it's not a glow plug issue.

The car runs just as it did before the swap but starts hard.

In all of Bladerunner's posts the images seem to be gone so I can't see what the cam locking tool looks like or where to buy one. If someone could take a picture of something they've made, or provide me with a link, that would be awesome. I clearly need to set the cam perfectly with the crank because I think it's causing the hard start issue. If anyone could shed some light on this I'd much appreciate it.

Newbie Joined: Aug 15, 2013 Posts: 4

Nothing eh? How about a Bentley for these cars ? I have the Haynes manual bit it doesn't go into vcds. I also have a Bentley for c4 cars but it doesn't cover the AEL.

Posted: Fri Aug 16, 2013 9:50 pm

Sorry, don't have the info you are wanting. Was going to say that I'd previously found that retarded timing causes cold start problems but you've already got that covered it seems.

One thing that might help is to know that the AEL engine is also used in the Volvo 850 and early S70/V70 TDI (not the D5 which is Volvos own). Don't know if you get those in Canada? Also the earlier 2.5 5 cyl transporter vans use the same basic engine.

Cheers

Nick

Bandwidth Buster Joined: Aug 12, 2006 Posts: 803

I cant seem to find the exact part you need at moment but it looks very similar to the top piece in this link,this is from a vw crafter 2.5,which uses a similar enigine

I made one from a piece of flat plate but they are available to buy cheap enough

i think its the same part as used on the 5 as the 4 cylinder

http://thumbs4.ebaystatic.com/d/l225/m/mN_K3QXZ2EAfKXDF7wPnP1Q.jpg

Posted: Sat Aug 17, 2013 7:43 pm

The cam timing tool can be simply made from some 5mm thick strip steel. The slot in the cam lines up parallel to the top face of the cylinder head. My improvised version is the spanner for replacing the disk on my angle grinder and has served me well for years and fits the cam perfectly.
If you are sure that your fuel injection timing is spot on, disconnect the temp sender connector at the front of the head. This will make the ECU think that your are in the North Pole and will give the glow plugs a longer per heat period.
These engines should start on the sniff of the starter and if not, I would be 99% sure that the timing is retarded. On my last C4 tdi (AAT) Vag Com told me that my timing was circa 85 and "too advanced" but it started perfectly, had impressive performance for a large vehicle and gave very good fuel consumption when driven sensibly.

Posted: Wed Aug 28, 2013 5:22 pm

This is the cam locking tool

http://www.lasertools.co.uk/item.aspx?cat=1066&item=547

I've bought this one, I've not used it yet but it does work.

Newbie Joined: Aug 15, 2013 Posts: 4

Thank you! Ordered. Will reset the timing once this comes in.

Needs to get out more Joined: May 03, 2011 Posts: 119

Not going offtopic, but my timing is t "55" and vag-com says it is "spot-on". Starts first time cold or during day. Cranks a few more times when sopped for a week, but nothing major.

But I was wondering if the cam was out of time by 1 tooth, the car could work normally or I would feel imediate trouble ?
A too advanced cam can produce high oil consumption? Still trying to figure out my 1l per 3000km oil burn. Rolling Eyes

Newbie Joined: Aug 15, 2013 Posts: 4

well now that it's really winter here (-10c and colder) the car is basically not starting. I timed everything using the cam lock and the car started like garbage when spot on timing according to VCDS. So I advanced the pump timing and it was much better, even though it was way out of spec according to VCDS. I am wondering if when the timing belt tensioner went a valve hit a piston even just slightly and I'm not getting perfect compression. So I'm going to do a compression test.

I'm just wondering if there's anythign else I should look for - I'm going to check all vacuum hoses, confirm glow plugs good, check/advance timing again.

Is there anywhere to get new glow plug connectors? Mine are garbage and I'm suspecting that that could be part of the problem. Plugs may be fine but aren't doing anything if they're not connected!