D5 (2005 on) Timing Belt One Tooth Out

[Jinxie]

Hi all,

I've just replaced the cam belt on my particular D5 and it appears I've got the new one on one tooth out. The problem arises because the old belt was not lining up the timing marks precisely against their counterparts. When the old cam belt was on, and the camshaft sprocket perfectly aligned, the crankshaft pulley mounting flange was slightly to the left of where it should have been. So I thought it wise to record this detail at the time in case it became an issue later. Anyway, over the course of the 2 weeks it's taken me (when I can get a few free minutes away to deal with it) I've forgotten exactly what I meant by "slightly" and the new "slightly" is clearly further to the left than the old one. This only became apparent after turning the engine over twice by hand after replacing the belt as they suggest you do in the manual.
The question is, how far out does the timing have to be before damage occurs on a D5? I have no idea how close the valves and pistons will be at one tooth out. I didn't feel or hear anything unusual on turning it over; just the usual compression bumps.
Any ideas?

[Clan]

Originally Posted by Jinxie

Hi all,

I've just replaced the cam belt on my particular D5 and it appears I've got the new one on one tooth out. The problem arises because the old belt was not lining up the timing marks precisely against their counterparts. When the old cam belt was on, and the camshaft sprocket perfectly aligned, the crankshaft pulley mounting flange was slightly to the left of where it should have been. So I thought it wise to record this detail at the time in case it became an issue later. Anyway, over the course of the 2 weeks it's taken me (when I can get a few free minutes away to deal with it) I've forgotten exactly what I meant by "slightly" and the new "slightly" is clearly further to the left than the old one. This only became apparent after turning the engine over twice by hand after replacing the belt as they suggest you do in the manual.
The question is, how far out does the timing have to be before damage occurs on a D5? I have no idea how close the valves and pistons will be at one tooth out. I didn't feel or hear anything unusual on turning it over; just the usual compression bumps.
Any ideas?

Being one tooth out makes a big difference to the engine , efficiency will be poor and possibly soot will build up. Best get the cover off again and the lower pulley to get the crankshaft in the correct poison . then fit the belt so that the scribed timing marl on the upper cam pulley is lined up as near as possible , normally you will get it just about spot on . don't forget four new bolts MUST be fitted to the crank pulley and angle torqued correctly .

[Jinxie]

It's just a hunch, but I'm thinking maybe that initial disparity with the old belt could maybe be due to it having stretched "slightly" over the course of its 70k miles and I was over-thinking things. Perhaps I should have ignored the fact it was "slightly" to the left as being due to its age (10 years) and mileage and simply fitted the new belt to match the timing marks exactly. But there again, if it was due to belt-stretch, then I would have thought the mark on the pulley mount flange would have been to the *right* of the lug on the crankcase rather than the left. Unless of course belts shrink over time rather than stretch!

[Clan]

Originally Posted by Jinxie

It's just a hunch, but I'm thinking maybe that initial disparity with the old belt could maybe be due to it having stretched "slightly" over the course of its 70k miles and I was over-thinking things. Perhaps I should have ignored the fact it was "slightly" to the left as being due to its age (10 years) and mileage and simply fitted the new belt to match the timing marks exactly. But there again, if it was due to belt-stretch, then I would have thought the mark on the pulley mount flange would have been to the *right* of the lug on the crankcase rather than the left. Unless of course belts shrink over time rather than stretch!

Of the hundreds of Volvo belts I've changed over the years the tensioner arrow pointer has always been still between the tolerance marks , Kevlar belts do not stretch .