Omega Owners Forum
Omega Help Area => Omega General Help => Topic started by: polilara on 29 August 2017, 18:46:14
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Hello all
When I start my V6 I hear something which I do not like. With Idling speed about 600 rpm I hear three sharp noises on regularly basis. The noises last together about 0.5 second and then there is silence about 0.5 second, during next 0.5 second I hear again these three noises etc. Just calculated that crank sprocket has 23 teeth and timing belt has about 10 times more teeth so while crank is rotating 10 rounds/second the timing belt is rotating one round/second.
But what it can be? If something in tooth side I should hear something 5 times/second and without brake. If something in back side I perhaps heard something three times/sec (without brake). When engine gets warm the sound disappears. That happens every day.
I changed timing belt + other parts about 500 km ago. During first wekks I did not hear this noise. Perhaps better to open cam cover and see. Any ideas??
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First thing I would do is to pull the Aux Belt off and run again briefly, that will eliminate, Aux Tensioner and Pulley's, Alternator, Power Steering and Water Pump, then go from there.
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Yes, thanks. That is something to be done first but I am afraid that it is not the case. Aux belt is rotating much faster than timing belt so difficult to imagine what else will cause a frequency that I hear once a second when engine idling. But I'll do that. Let's see.
It is difficult to explain this in English but if you divide one second to six parts (1,2,3,4,5,6) I hear a 'click' in time 1 and a 'click' in time 2 and a 'click' in time 3. Then in time 4, 5 and 6 I do not hear anything. Like there was a loose tape in outer surface of the timing belt which touches the cam cover in top corners etc. But what happens when engine is getting warm.
Today I take my bike when going to work...
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Good to have a bike!
Removing aux did not change situation. Took cam cover away. Timing belt seems to be a bit aside of cam sprockets.
1. In bank 1-3-5 I can see about 3.5 mm cam sprocket teeth in front of the belt and in bank two maybe 3 mm. So belt is a bit "back".
2. Belt seems to be against rear flanges of the guiding rolls. Rear flanges slightly polished.
3. All old belts I found have GM number 9 128 500 39 while new one (Gates) is GM 95522522
4. Rotated engine manually 15 rounds, nothing abnormal can be seen in teeth or back side.
5. Tensioner have same SKF numbers than previous, Guiding rolls seem to have same SKF "main number" other markings differs.
Should I assemble everything back except cam cover and start the engine to see something or just buy a new belt with GM number 9 128 500 39.
Can a new belt be noisy when cold, never heard
What this really can be?
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Some years ago I had noise problems on my V6 Omega after fitting new belt and pulleys. I had bought the belt kit from a Vauxhall main dealer, so I returned it and got another one. That was similarly noisy, so I returned that one and bought an SKF kit, which was silent. The noise was not the same as yours, it was a whine varying with engine speed. My theory is that the belt slipping through the V-pulley whined at certain temperatures.
I have since fitted a variety of cam belt kits, but never had any noise problems.
If you still have the old belt, fitting it on your new pulleys would prove whether the belt is the problem.
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I had a similar problem a few years ago. Turned out to be a small leak in the exhaust manifold gasket. The clicks were the gas escaping through the leak, when the engine & manifold were hot something must have expanded & the problem stopped!
Try listening in that area.
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Thanks for comments, I try to start the engine today without cam cover just to see whether the frequency (of the three clicks) really is once in a time belt round. Estimation is that when idling 600 rpm timing belt rotate once/sec and crank 10 rounds/sec. There is a text and number in the outer surface on the timing belt. If I hear the sound allways when the text part of belt is in the same place then the reason can be the belt itself. Can it be bent when tensioned so that it touches e.g. to the steel plate/cover behind the cam sprockets.
Test with old belt is a good idea. Have to study those leakages in exhaust, too, even it is difficult to understand that as when Idling 10 rounds/second each cylinder has power stroke 5 times/sec so I guess leakage sound should come much more often than once a second. But let's see, usually I think in a wrong way...
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Hello
Started engine without cam cover.
Seem to be once/belt round Have to study more.
Is it normal that about 3 mm cam sprocket teeth are "free" in front of the belt. Is it possible that the guiding rolls locate the belt too far to the rear side.
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You have definately fitted the pulley spacer washers behind the correct pulleys havnt you. The lower pulley (central or eccentric type )has a thicker spacer than the top eccentric pulley
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Hello
I bought a "Timing Belt Package" in a big box with GM-logos and texts. Also all boxes I found inside the package had GM texts. The package included the base plate where both upper guiding roll and tensioner we ready installed. Then there was another smaller box including lower guiding roll and spacer for that. I have old parts still lelft so I can make a verification.
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i had a gm kit fitted last time out and it made a chirping noise like a baby bird (chick) it died down after a few thou miles. also removed the aux belt and it made no difference, cam
belt cover also removed still the same. i put it down to the white lettering on the belt passing over the pullys :-\
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Baby bird chirping noise is exactly what it is. This noise is coming from top like cam sprockets did not like the teeth in certain part of the belt. Then silence, that part continues down to lower idler, crank, tensioner and up again and the noise starts again etc.. Can clearly seen as noise starts always when white text in back of belt is in certain place coming to cams 3&4. So it is not when text is against idlers or tensioner.
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Look at this
https://youtu.be/2oA3VBB6hGA
Chirpy Chirpy Cheep Cheep
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Did anybody see my video?
I today started the engine again (noise was there) and during the engine running I injected some drops of water to the timing belt back above cam 1 sprocket. As my hands were shaking some drops fell to the sprocket teeth, too, and after one second all noises disappeared. Remember in 70' when some deposit was knocking between piston and head some water through carburetor when engine running helped in seconds.
So should I lubricate the belt with silicon or just assmble everything back and forget the whole thing?
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I checked once again the belt tooth by tooth. It is perfect. On tooth is a bit white in the bottom. Perhaps the seam area or is this seamless?
I should assemble it today to be able to drive tomorrow. Understand it is difficult to give any recommendations in this case but what you would do:
1. New Belt
2. Light lubrication with silicon (both sides)
3. Just leave as it is
Please comment
https://youtu.be/2oA3VBB6hGA
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Congratulations on your research and testing. Have you tried replacing the old belt yet? It sounds like the belt is the culprit.
My belief is that it's pulley bearings that fail, not belts, so old belt should have life left in it.
If you want a cheap new belt, there is a man here selling new cam belt kits lacking one pulley for £19.99.
http://www.ebay.co.uk/itm/AC-Delco-Timing-belt-kit-Vauxhall-Vectra-Calibra-Cavalier-2-5-Omega-2-5-2-6-3-0/222619968296?_trkparms=aid%3D111001%26algo%3DREC.SEED%26ao%3D1%26asc%3D20131017132637%26meid%3D8199d8265d5442d7a714033d6dbafc5c%26pid%3D100033%26rk%3D1%26rkt%3D8%26sd%3D222619968296&_trksid=p2045573.c100033.m2042
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James has just fitted one of these kits plus pulley to my 2.6 and it is running like a well oiled sewing machine no tweeting birds.Thanks again James lovely job jobbed.
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Thanks for comments and tips of that cheap kit. To deliver that in Finland might take time, let's see. Is he someone from OOF to contact?
I took the new belt away and found that new tensioner and idlers have quit big clearance, is it normal?? I checked the old ones and they had much smaller play even they have been there 60 000 km. Have anybody idea is it OK that new parts have much clearance or should they be totally tight when new. Is there inside just a single bearing when it is clear that there is some play.
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Maybe. I have found my spare (INA) cam belt kit and checked. Belt width is 29.58mm, pulleys have one flange normal to flat and one angled; flat width is 31.29mm, top is 33.50mm. I imagine kits are all the same. I have fitted an INA kit and is still running normally. Pic follows.
(https://www.dropbox.com/s/dol2q6nl0cankqw/BODY%20HOLE.jpg?dl=1)
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Sorry, wrong pic.
(https://www.dropbox.com/s/nru5bbv1jvtjbnl/cam%20belt.jpg?dl=1)
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Thaks for nice pic's. Sorry I did not explain my 'clearance case' well enough. Language problem...
I mean that all the new rolls like idlers and tensioner swing when installed. They do not have axial play and they do not have radial play but they swing more than the old ones. Is this normal? As you seem to have new parts on table can you (or anybody else having new parts) do new parts swing.
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Thaks for nice pic's. Sorry I did not explain my 'clearance case' well enough. Language problem...
I mean that all the new rolls like idlers and tensioner swing when installed. They do not have axial play and they do not have radial play but they swing more than the old ones. Is this normal? As you seem to have new parts on table can you (or anybody else having new parts) do new parts swing.
i am afriad Ido not understand how your pulleys 'swing. The only freedom mine have is to rotate. With some kits I have had is to rotate.
With some kits I have had to use the original back plate. More pics follow, please explain how your pulleys swing.
(https://www.dropbox.com/s/wtmbakt05i9btag/CAMkitFLAT.jpg?dl=1)
(https://www.dropbox.com/s/bi66knx2v8uxs2o/CAMkitUPRIGHT.jpg?dl=1)
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Mine has some clearance in the bearings.'swing' you are reffering to .this is a small clearance designed into the bearing to allow for heat expansion. My old pulleys were skf and my new ones are also skf from an ac delco kit.i wouldnt say my new ones feel to have any more or any less play than the old ones but then the old ones were supposedly only 22000 mile old anyway.the white you refer to on the belt ? Is that just a colour or is there a build up / deposit of paint / ink that will wear off or can be removed?
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Thanks for your activity here. Difficult to explain in English but I try:
In the fig you enclosed the upper guiding roll is bolted to the base plate. If you press with one hand the base plate against the table and with other hand try to bend or tilt the upper guiding roll without rotating it roll can you feel a movement. Like you test a normal ball bearing to see the clearance. If not clear I try to make a drawing of this.
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Ps. The bearings in the rollers are double row bearings.hence sligtly wider than a standard single row bearing .they are used as they are more stable / stronger and keep the roller running true .
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Thanks for your activity here. Difficult to explain in English but I try:
In the fig you enclosed the upper guiding roll is bolted to the base plate. If you press with one hand the base plate against the table and with other hand try to bend or tilt the upper guiding roll without rotating it roll can you feel a movement. Like you test a normal ball bearing to see the clearance. If not clear I try to make a drawing of this.
If you mean the pulley rocks on the base, I can detect no movement at all in my kit. Pressing as hard as I can, I can deform the pulley slightly, but I feel no slack in the bearing. Pic shows how I pressed on the bearing.
(https://www.dropbox.com/s/5tzusbvao9qyfjm/PULLEYrock.jpg?dl=1)
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Thanks for the last pic. Now if you press the tensioner in a position where your left finger is and lift it from the position where your right finger is. Then opposite way you press the right finger area and lift the left finger area. Can you feel the play or clearance of e.g. 1 mm.
If not clear I make a video to youtube how my rolls "swing" (and promise to learn more English, too).
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Hello again
So here new tensioner (driven 500 km) bolted to old base plate, I feel the swing or clearance or play in my fingers, it can be heard as well. The whole base plate is also moving a bit as the table was not as flat as the cylinder head is. Is this "play" normal. It is similar in both new idlers, too.
Question is that is this normal? Can you see this clip?
https://youtu.be/G0lsavOnsr4
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should not have that amount of movement on the bearing, usually a tiny amount, very tiny amount is the movement between bearings and runner by the look of the bearing you have in the video its a grad d-f bearing not any good for a timing belt. this movement can be that the timing belt was to tight.
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Bearing is SKF BB1-0207 B Italy B 07 12 032N, running some weeks. Tightness was OK acc. to rules 3-4 mm over the mark.
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Sorry SKF BB1-0207 B Italy B 07 17 032N
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There is no play in my pulleys, and I cannot make it click as it rocks, as yours does.
For what it's worth, my tensioner is stamped SKF 337025 DC F-244449776, the other pulleys are labelled SKF 337185 A FRANCE J117 15:27, and the alloy casting SKF GERMANY 337054 FB.
Do both pulleys rock and click when rocked? That does seem wrong and may well be your trouble.
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OK, I have same tensioner number SKF 337025 DC F-24449776 (one '4' less, perhaps mistake) The number I gave is stamped to the SKF bearing outer ring.
I check the number of other pulleys soon. They rock in the same way. I try to give a clear value of this perhaps one mm = 0.04 inches.
I also believed for a while that these pulleys might cause problems. When some discontinuity in belt passes them they give some noise... difficult to understand. I will test with brand new belt soon. It will come tomorrow. If that does not help I put back the old base plate, pulleys and tensioner just for test. Terrible work.
Is it so that your tensioner do not rock at all? Even that 1 mm. It is not very probable that my all parts are bad. If 1 mm rock is OK then the belt just was bad. The kit is GM 9201887+idler GM 9196294+belt (Gates) is GM 95522522.
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i have just checked 4 brand new cam kit sets (delco)and also my original old 22000 mile conti old rollers.all have similar amount of play as yours does.
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i have just checked 4 brand new cam kit sets (delco)and also my original old 22000 mile conti old rollers.all have similar amount of play as yours does.
These are good news, thanks a lot for your effort. Then we can guess it is the belt, I get it soon and come back with results if anybody has nothing else in mind I should check before that.
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New belt installed, no sound/noice at the moment, lets wait. I checked all my old belts. They all have some straight wear stripes in back side. This noisy one has sinuous stripes like snakes. Perhaps the belt was bad or something else...
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Yup, that's good news, long may it remain silent, and really it was the obvious culprit. This forum has had such problems before, but you are the first member to swop just the belt and prove it. Thanks and congratulations.
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Strange!
After 500km the sound is back when cold - once/timing belt round. After 15 minutes drive disappeared totally.
What this really can be.
I really do not understand anymore. One belt round is about 10 crank rounds, 5 cam(s) rounds and about 15-20 idler/tensioner rounds.
It is quite unrealistic to think that if e.g. idlers/tensioner were not rotating parallel to crank/cams it would eat the belt so that it starts to give this noise.
Perhaps I should change the whole kit again? What do you think.
I understand it is difficult to give recommendations e.g. "just live with it" but what did you do by your self.
Who was selling those 40 GBP kits? I am ready to start from the beginning.
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Hello, any opinions?
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hi. is the new belt the same make as the other noisy one ? . did you check the spacer behind the lower roller was the thicker one. are there any signs of the belt running off to one side. looking at mine the belt sits nicely on the 4 cam wheels with only a couple of mm or so visible
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also are there any localised shiny spots on the edge of the belt ?
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hi. is the new belt the same make as the other noisy one ? . did you check the spacer behind the lower roller was the thicker one. are there any signs of the belt running off to one side. looking at mine the belt sits nicely on the 4 cam wheels with only a couple of mm or so visible
Thanks for comments:
1. Yes, Gates belt in GM package sealed with GM Hologram in both cases.
2. Spacers are in their correct position.
3. As I wrote Aug 30.
(1. In bank 1-3-5 I can see about 3.5 mm cam sprocket teeth in front of the belt and in bank two maybe 3 mm. So belt is a bit "back".)
(2. Belt seems to be against rear flanges of the guiding rolls. Rear flanges slightly polished.)
Have to check in the near future whether the base plate is a correct one. All parts were from GM kit No. 9201887.
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also are there any localised shiny spots on the edge of the belt ?
Belt was sent to supplier. I believe there were no spots.
As I wrote Sep 9: (I checked all my old belts. They all have some straight wear stripes in back side. This noisy one has sinuous stripes like snakes.)
Like it did not run a "straight path")this base plate worries me.
I ordered a new GM kit including everything again. Put it there when it arrives.
New thing I found this morning is that cold engine is silent in first minute and the sound starts after that and then disappears after 15 minutes drive.
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Ok . . Do you have all your ORIGINAL bits ? And was it silent running on these ? . Did you notice if the belt was " a bit back " as you said on these parts? . Probably not what you would have been looking for then though. Try to compare everything with your new parts looking for spacer thickness and anything that could cause the belt to run off centre such as burrs on mounting faces or the tensioner bolt post being bent ? If im correct here there are 3 different baseplate types but i think there is only one style for a later engine with the offset top roller.googling various images gives a general idea of the belt to pulley front distances but its not always easy to see in the pictures.the belt on mine was same on all 4 and sits just after the tapered edge.my old rollers dont look exxecively shiney on any one side .maybee compare with your new kit when it arrives.
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Ok . . Do you have all your ORIGINAL bits ? And was it silent running on these ? . Did you notice if the belt was " a bit back " as you said on these parts? . Probably not what you would have been looking for then though. Try to compare everything with your new parts looking for spacer thickness and anything that could cause the belt to run off centre such as burrs on mounting faces or the tensioner bolt post being bent ? If im correct here there are 3 different baseplate types but i think there is only one style for a later engine with the offset top roller.googling various images gives a general idea of the belt to pulley front distances but its not always easy to see in the pictures.the belt on mine was same on all 4 and sits just after the tapered edge.my old rollers dont look exxecively shiney on any one side .maybee compare with your new kit when it arrives.
Thanks for comments, all parts similar to original and engine silent with old parts but:!!!
I think I found the root cause. What I saw when taken the base plate away was that the tensioner was not parallel with the bottom part of the base plate/cylinder head surface. I has alignment error so that the water pump side of the tensioner is closer to cylinder head than the other side. Alignment error can be seen by eye when verified with old parts. So this leads to situation that when belt goes here in "loose" side to cam No. 1 tensioner lead it too back which is seen also in cam sprockets 1&2. I measured 3.5 mm teeth in front of the belt. Belt back side is full of snakes again and amount of rubber dust is big - above water pump and inside the base plate below upper idler. New parts coming tomorrow so I keep you informed...
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Just completed with new set. Belt is now where I suppose it should be, perhaps 2-3 mm more front than earlier. I rotated manually the engine about ten rounds when trying to get timing and tensioner right. When running silent again and hopefully in long term, too. Tensioner and other rolls now parallel now, let's see.
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Ah that sounds good. You may have it sorted. Any pictures ?
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Yes, it really 'sounds' good as there isn't actually any noise anymore. Let's see after next 500km is the behind...
I try to enclose some picks of the rubber dust and wrong belt location if I succeed to do that.