Clio 1.5 DCI Timing....I am lost on this one....Cambelt
Discussion
Hey guys,
Hopefully someone may be able to help me get my head around this one.
I bought a cheap economical shed to run to work and back as I am considering a Cerb next year, my trusty reliable STI will make way for something that will break down all the time :P I did the usual full service on the Clio and I intended to swap the timing belt/water pump too. Done plenty of changes on my Pride and Joys over the years but this little thing has me stumped.
I bought the pins to lock cam and crank, however the timing was seemingly way out. The car still ran and didn't smoke. So after taking the cylinder head off I seem to be completely lost.
With the cam sprocket locked using the tool, number 1 cylinder has its inlet valve fully open and the 3rd cylinder its exhaust valve? This pin should be in at TDC so would mean a bent valve. Also with the keyway on the crank at 12 o'clock, intended to be TDC I think, the pistons are all at the midway point on mine.
So it seems as it was currently timed the car would have periods of the piston rising with the inlet valve open and vice versa. And when set as factory intended the pistons are all at the midway position and not TDC, with the inlet valve open fully on the first cylinder.
I am a little confused. The most awkward car to access I have ever worked on too, nearly everything is hard to get at lol!
Hopefully someone may be able to help me get my head around this one.
I bought a cheap economical shed to run to work and back as I am considering a Cerb next year, my trusty reliable STI will make way for something that will break down all the time :P I did the usual full service on the Clio and I intended to swap the timing belt/water pump too. Done plenty of changes on my Pride and Joys over the years but this little thing has me stumped.
I bought the pins to lock cam and crank, however the timing was seemingly way out. The car still ran and didn't smoke. So after taking the cylinder head off I seem to be completely lost.
With the cam sprocket locked using the tool, number 1 cylinder has its inlet valve fully open and the 3rd cylinder its exhaust valve? This pin should be in at TDC so would mean a bent valve. Also with the keyway on the crank at 12 o'clock, intended to be TDC I think, the pistons are all at the midway point on mine.
So it seems as it was currently timed the car would have periods of the piston rising with the inlet valve open and vice versa. And when set as factory intended the pistons are all at the midway position and not TDC, with the inlet valve open fully on the first cylinder.
I am a little confused. The most awkward car to access I have ever worked on too, nearly everything is hard to get at lol!
If the pistons are all level than you are at 90BTDC/ATDC, at this point you would expect to see the inlet valve on one of the cylinders to be well on it's way to being fully open and the exhaust valve on another of the cylinders to be just past fully open. I imagine that the markings you are interpreting as TDC could be 90BTDC, this is a common situation with some engines as it is a 'safe' position where the valves regardless of the cams position will not strike the pistons, this makes it a good position to set the Initial cam timing with no danger of bent valves due to the cams rotation when aligning the sprockets.
Dave
Dave
Thanks Dave,
It would make sense for sure with all the pistons out of harms way. I think I recall people removing injectors and using wire to find the TDC point though, I am sure they are refering to the first piston being at the top! I am just not certain. The timing it was at was even more strange though.
I don't know diesels but I wouldnt have expected it to run ok the way it was, inlets open with the piston rising and exhausts open with it falling.
I will investigate a bit more today!
It would make sense for sure with all the pistons out of harms way. I think I recall people removing injectors and using wire to find the TDC point though, I am sure they are refering to the first piston being at the top! I am just not certain. The timing it was at was even more strange though.
I don't know diesels but I wouldnt have expected it to run ok the way it was, inlets open with the piston rising and exhausts open with it falling.
I will investigate a bit more today!
If the engine was running ok with the timing as it is does it matter where the piston is??
As some say timing marks for crank/ cam are often in the halfway "safe" position so you dont have to worry about the cam position when doing engine work (its easy to bend valves when refitting a cylinder head or similar) The 1.5dci locks the cam at @ the 8 'o'clock position & the crank at the front of the block (with the keyway at 12 'o' clock) in these positions it will be fine. Make sure when fitting the new belt the lines on it align with the dots on the cam sprokets.
As some say timing marks for crank/ cam are often in the halfway "safe" position so you dont have to worry about the cam position when doing engine work (its easy to bend valves when refitting a cylinder head or similar) The 1.5dci locks the cam at @ the 8 'o'clock position & the crank at the front of the block (with the keyway at 12 'o' clock) in these positions it will be fine. Make sure when fitting the new belt the lines on it align with the dots on the cam sprokets.
Cheers guys, I get to work on it again this weekend as I have some time. Yes the cylinder arrangement is opposite to most cars thanks.
It was running before yes but it was timed strange. I figured out the deal with the piston position. On this car the crank pulley is not keyed to the crank, really poor design. But still has a keyway making me think it was. So when I rotated the crank with the alternator belt pulley missing, which holds the crank pulley in position by friction alone, the crank must have moved further than the rest of the pulleys and belt. I had marked the crank pulley as the bolt restricted view of the keyway. But as it turns out the correct timing position on the crank is TDC on cyclinder 1, which is gearbox side opposite to most cars.
Now the problem I have to figure out is why with the timing pin in the camshaft, can only go in one place 8 o'clock, is locking it into position with cylinder 1's inlet fully open. Somebody must have had the camshaft or pulley, which is keyed on this according to manuals, off and back on wrong.
It was running before yes but it was timed strange. I figured out the deal with the piston position. On this car the crank pulley is not keyed to the crank, really poor design. But still has a keyway making me think it was. So when I rotated the crank with the alternator belt pulley missing, which holds the crank pulley in position by friction alone, the crank must have moved further than the rest of the pulleys and belt. I had marked the crank pulley as the bolt restricted view of the keyway. But as it turns out the correct timing position on the crank is TDC on cyclinder 1, which is gearbox side opposite to most cars.
Now the problem I have to figure out is why with the timing pin in the camshaft, can only go in one place 8 o'clock, is locking it into position with cylinder 1's inlet fully open. Somebody must have had the camshaft or pulley, which is keyed on this according to manuals, off and back on wrong.
Edited by Keta on Thursday 11th April 09:54
Yeah everything I have read indicate with the keyway at 12 o'clock and resting against the locking pin, as it currently is, it should be at TDC. And it is perfectly at TDC on cylinder one. Not slightly shy or anything, spot on.
This of course indicates that something is amiss with the camshaft side of things. The locking pin goes through a hole in the sprocket and into the block. At 8 o'clock as shown in diagrams. Yet this is with cylinder 1 inlet fully open on mine, when it should be closed as the piston is at full compression point. I did wonder today if the camshaft sprocket could go on the other way around, then the 8 o'clock would be 4 o'clock and then the roughly 90 degree turn would make sense. But it is the correct way around.
I decided I would at least remove the sprocket on the camshaft and make sure it is keyed, if it is and correct I am still lost. I can probably time the engine anyway as far as valves and pistons go, but the high pressure fuel pump is guess work. The camshaft sprocket is going to be a nightmare to remove anyway, old belt trick didn't work I will have to fashion some multi pronged tool and try again at the weekend.
I had previously found with the fuel filter, when I replaced it, a couple of pipes were also plumbed into the incorrect places. And these were very plainly colour coded.
This of course indicates that something is amiss with the camshaft side of things. The locking pin goes through a hole in the sprocket and into the block. At 8 o'clock as shown in diagrams. Yet this is with cylinder 1 inlet fully open on mine, when it should be closed as the piston is at full compression point. I did wonder today if the camshaft sprocket could go on the other way around, then the 8 o'clock would be 4 o'clock and then the roughly 90 degree turn would make sense. But it is the correct way around.
I decided I would at least remove the sprocket on the camshaft and make sure it is keyed, if it is and correct I am still lost. I can probably time the engine anyway as far as valves and pistons go, but the high pressure fuel pump is guess work. The camshaft sprocket is going to be a nightmare to remove anyway, old belt trick didn't work I will have to fashion some multi pronged tool and try again at the weekend.
I had previously found with the fuel filter, when I replaced it, a couple of pipes were also plumbed into the incorrect places. And these were very plainly colour coded.
Yeah it has a mark to line up too. I really don't understand what has happened to it for the camshaft to be different to factory setting. I will still remove the sprocket and see if it is keyed as it should be.
I saw the old timing was not as the books said but still marked it on the crank sprocket anyway. I didn't at the time after seeing the keyway realise the sprocket itself isn't keyed. Why have a keyway without a keyed sprocket, odd car! So yeah the timing will be lost as the crank moves independant of its sprocket.
I will see what comes of the removed sprocket, failing that custom timing job! Fun and games, thanks for the help guys I'll keep you posted
I saw the old timing was not as the books said but still marked it on the crank sprocket anyway. I didn't at the time after seeing the keyway realise the sprocket itself isn't keyed. Why have a keyway without a keyed sprocket, odd car! So yeah the timing will be lost as the crank moves independant of its sprocket.
I will see what comes of the removed sprocket, failing that custom timing job! Fun and games, thanks for the help guys I'll keep you posted
Well after the help of my father and a lengthy bit of scaffolding the camshaft sprocket is off, geez it was tight. After sliding it off it was evident it was out by a long shot, probably 180 degrees. The key on the sprocket had sheared off and it looks like someone has put it back on in a random place and then tightened the s
te out of it. I am not sure what the hell has gone on with this but it looks like they have just slapped the sprocket back on and then custom timed it, by fluke or skill the timing was pretty good!
After drilling the sprocket and making my own pin (key) it is now tightened back on. Now when locked with the timing pin the valves are closed at TDC and the exhaust valve opens after a 90 degree rotation of the cam. Seems I am finally where I need to be!! Just put the bloody thing back together now!
Thanks for all the support guys, I was beginning to think I was to blame and losing my marbles. For once I think the mechanics fee is perfectly justified for this job, I consider the car a swine to work on. Access seems to be a nightmare on every part. Not helped along by previous bodged jobs on every turn!
te out of it. I am not sure what the hell has gone on with this but it looks like they have just slapped the sprocket back on and then custom timed it, by fluke or skill the timing was pretty good!After drilling the sprocket and making my own pin (key) it is now tightened back on. Now when locked with the timing pin the valves are closed at TDC and the exhaust valve opens after a 90 degree rotation of the cam. Seems I am finally where I need to be!! Just put the bloody thing back together now!
Thanks for all the support guys, I was beginning to think I was to blame and losing my marbles. For once I think the mechanics fee is perfectly justified for this job, I consider the car a swine to work on. Access seems to be a nightmare on every part. Not helped along by previous bodged jobs on every turn!
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