Omega Owners Forum
Omega Help Area => Omega General Help => Topic started by: JamesV6CDX on 20 September 2015, 19:30:57
-
My V6 is making a horrible noise, and aside of a short period where it was much better, it always has!
https://www.youtube.com/watch?v=gErkVUU93yM (https://www.youtube.com/watch?v=gErkVUU93yM)
The story behind it is that the car was once a 2.6. I transplanted a 3.2 block, and then fitted late 3.0 heads (which are the same as 3.2 heads) with 3.2 G and J Cams.
When you start the car from cold, it's silent. Beautifully silent, no tapping or knocking.
As it starts to warm up after a few minutes of idling, (maybe 2-3 minutes) a "tap tap tap" noise starts to creep in... and before long at all it's just like it is in this video.
If you then drive the car for a good distance, say ten miles, it goes quiet(ish) again, but is still detectible.
I don't think it's anything terminal. It's done about 700 miles like it.
New oil went in at the time of the top end rebuild. After 200 miles and this problem still being there, some wynnes lifter treatment went in. No difference.
A further 500 miles later, (today) I dropped the original (I think 5/30 fully synth) oil and let it drain. I then refilled with 10/40, and ran the engine for an hour. I then drained this new oil (which came out looking as good as it went in) and put ANOTHER load of clean 10/40 in.
During this the sump has been off and the strainer is clear.
Does anyone have any views on this noise? Keep plugging on with more short oil changes?
Sometimes I think it sounds like a lifter, and other times I do not!
The car pulls like a train and there are no nasty noises when driving and no oil pressure lights etc.
I'd be v grateful for your views, please :y
-
Just because I know I will be asked:
1) Cambelt kit is brand new, 700 miles ago. (I know this doesn't always mean it's foolproof)
2) Cam bearing caps are the correct ones originally from the heads, are in the correct order and rotation, and are torqued properly
3) Water pump etc etc pulleys are tight. (noise is still present if you run it briefly with the aux belt off, so it's not aux related)
:y
-
Would it be worth fitting an external oil pressure gauge, start the motor from cold and watch the pressure as it warms up and starts to tap, at least you can rule out oil pressure
Andy
-
Hi James :y You said some months ago now that you had a tapping lifter on this car,And that it goes silent once warmed up.
Well i have too,And as time goes on they do get louder and get to the point where they dont go silent when the engine is fully warmed up.
But on saying that:- yours is not really a constant tap,tap,tap. Meaning on the vid it seems to miss a beat every few taps,And it does seem very loud if it is a lifter.....Is it a lifter that has failed suddenly. :-\ Just a thought.
-
That sounds more sinister than sticky lifters... Piston or crank related :-\
-
That sounds more sinister than sticky lifters... Piston or crank related :-\
Crossed my mind mate I must say!!!
-
On the other hand. It's lovely and quiet after it's run for a bit. I did 100 really, really harsh miles the other day and it went like stink, which I guess means it might not be? :/
-
hydraulic tappets.
Anything else is there for good once the oil is hot and thin.
-
It sounds like it's coming from the passenger side...
-
Will take someone like you james not long to rule out lifters...See post #1 http://www.omegaowners.com/forum/index.php?topic=131643.0
-
From about +14 to 16 seconds I can hear a dull knocking that then gets masked by the more mettalic noise. Is the compression on each pot within limits ???
-
Does sound a duller knocking than you'd get out of a lifter but trying to diagnose engine noises from a recording is a bit futile.
I have heard quite a few V6s making similar noises when idling. I think Andy's suggestion of checking the oil pressure is a good starting point.
Does it remain at higher revs or disappear above idle?
Does it get any better or worse under load?
Performance isn't really an indicator, IMHO. Performance won't be affected unless the piston rings or valves aren't sealing.
-
You did use the T-vents from the original engine?
-
You did use the T-vents from the original engine?
No, but I compared them, and they were exactly the same :y
-
In reply to your questions kevin, you don't really hear it much above idle speed, if you were to hold the revs at 2k rpm, it would not be heard.. Likewise it cannot be heard when driving
-
I can't answer the question about under load, as I cannot hear the noise at all when driving :)
-
Odd, as I thought I had similar issues as yourself, but mine's actually more audible under load and with revs... I'll be starting with an oil change and go from there. Will watch this thread with interest, and hope you get sorted very soon. :y
If JamesV6CDX has an engine fault he's unsure of then none of us are safe!!! :o
-
You did use the T-vents from the original engine?
What are T-vents used for and where are they in the omega ???
-
You did use the T-vents from the original engine?
What are T-vents used for and where are they in the omega ???
Inside the cam/lifter area they channel oil away IIRC?
-
Hiya, do one little test for me, when the engine is running lift off the oil filler cap and tell me if it changes the level of noise.
-
i was going to suggest that but there seems to be no filler cap in the video....
-
It's there... Just fitted with without the filler neck and therefore obscured from the camera by the cable tray :y
-
That doesnt sound like lifter noise. Possibly bearing noise cam belt related , there has been a few duff cam belt kits around :-\
-
Here's a daft question for you......are all your spark plugs tight enough?
I've seen it before albeit not on an Omega!
-
I'm open to all ideas guys :y
Oil has been draining since weekend... Will refill and do a video from cold tomorrow :y
-
That engine was from the 120k MV6 estate and did not have that sound with the old 3.2 heads so I would say it is from the 3.0 heads you have added to the engine. I know you have done the job 100's of times but when you did cam covers were all the oil ways/drains clean :-\
-
is it louder with the filler cap off (i.e. is the noise coming from the top end)? difficult to tell but sound like belt related to me not valve.
-
Took the Cambelt kit off today.
All good. Idlers all run totally smooth.
I took the 246 rocker off. All looked good. I took the camshafts out.
It would appear some metal has broken off under the Inlet camshaft on the head.
Bugger it.
-
Metal has broken off? Sure it's not just a rough edge on the casting?
A picture would be handy. :y
-
Metal has broken off? Sure it's not just a rough edge on the casting?
A picture would be handy. :y
I thought the same, and the fact there is no sign of any foreign object or filings would be consistent with a rough edge...
No explanation for the noise, though!
-
While the cam cover's off, try to push the top of each lifter down with a bit of wooden dowel or similar. If you can compress any, or if there's a considerable clearance in the first place, it might point to a lazy lifter.
-
While the cam cover's off, try to push the top of each lifter down with a bit of wooden dowel or similar. If you can compress any, or if there's a considerable clearance in the first place, it might point to a lazy lifter.
I have done that - they are all solid :y
-
I booked today off work to play cars
I've fitted a set of known good lifters to the 2-4-6 side where the noise originated from
I cleaned them out as per the guide.
She was very noisy for 20 mins but now idling silently and has been ticking over smooth as silk for the last 40 minutes
There is a slight noise which sounds somewhat like a belt rub which was there before. It may be because all the belts and pulleys are new, as they are fitted correctly.
I guess the real test will be the next cold start.
I did take a picture of that rough edge, I will upload it v soon :y
-
Started from cold today
Sweet as a peach for 7 minutes, then the dull "knock knock knock knock knock knock" crept back in...
It seemed to take longer to come and not be quite as loud.
But it's still there.
This is the first time I've run it from cold since 3 back to back oil changes....
I have had a thought.
The Cambelt kit is the one fitted to the old engine when it seized
Clearly I fitted a brand new belt but the rollers were on the old engine when it seized
The feel absolutely fine by hand.... But I wonder?????
I totally believe Joff of course that the block was quiet before.
Valve train seems fine??
Hmmmmmmmmm
-
For peace of mind is it worth checking oil pressure?
-
I will
This is how she sounds now, video below
All I have done is
1) lifters on 246 bank all changed for known good used ones
2) Oil and filter x 3 (I basically dropped oil, ran for an hour, dropped oil, ran for an hour, dropped oil one last time and refilled.
You can hear it's noticibly quieter
http://youtu.be/f1AUB6zaEj0 (http://youtu.be/f1AUB6zaEj0)
Thoughts please :y
-
To add, there is still a trace of the noise. But it really is a trace compared to before!!
-
Loose/blown exhaust manifolds sound like that :-\
-
That's a big difference! :y
-
It's totally not manifolds, I can assure you :y
It does sound better eh? Not 100% though!
-
Have you checked that the sump and, particularly, the oil pickup are clear?
-
Have you checked that the sump and, particularly, the oil pickup are clear?
Yes yes :y
-
(http://i89.photobucket.com/albums/k205/jamesv6cdx/Mobile%20Uploads/image_zpsq5gynldr.jpg)
-
Signs of 'pick up' on the bearing face ? due to lack of oil? :-\
The random beating with a blunt object is puzzling :-\
(http://i89.photobucket.com/albums/k205/jamesv6cdx/Mobile%20Uploads/image_zpsq5gynldr.jpg)
-
Indeed. That has always been there in my ownership even when the heads were on my 3.0
It does look as if something has broken off where the very front of the inlet camshaft sits though
-
My thoughts are either a foreign object or an incorrect cam that has a lot of endfloat, so the cams areas have moved around. The fact you have aluminium broken off both sides of the bearing means it is unlikely to be a casting fault / fatigue that has caused the issue but something hitting it. The gouges on the head look reminiscent of when a Honda 250 I had, sh!t metal choke flap broke up and was ingested by the engine. The piston and to a much lessor extent the head was marked similar to that. If there is no foreign object in the cam box then I would check the oilways and sump as you don't want a blocked oil feed and finding it would confirm the source of the problem.
I think it is unlikely, but where the left and right cam sprockets are different to allow for the offset of the cylinder banks, has there been an issue there?
-
pm sent :y
-
So do we concur something has broken off as opposed to just the way it was cast?
Thing is... The strainer is clear, as are the t vents. What else is there to check other than actual oil pressure?
I'm guessing bare minimum I need a new head and cams then, possibly 2? :(
-
What do the journals on the cams look like?
The head is soft - the cams hard. If the cams are good then I wouldn't be concerned about minor surface marks on the journals,
I would be most concerned about excessive clearance allowing the cams to rattle around and/or lack of oil pressure.
-
Tapping sounds a lot like Connecting rod bearing issue imho ?