sgraber
|
| posted on 28/3/08 at 03:52 PM |
|
|
New Game - Guess the awful engine noise.
Apparently there is something wrong with this engine from the get-go. This is a 20v Silvertop 4AGE just installed to replace the dead 180,000 mile 16v
4AGTE in my La Bala.
Notice that the new engine sounds good at startup but the noise gets progressively louder.
http://www.youtube.com/watch?v=BK_hqG0d5QE#GU5U2spHI_4
Timing is spot on, valve clearances are within .001, new oil, new filter, no sludge in engine, nothing in the combustion chamber, healthy plugs. The
engine was primed and oil pressure brought up with the plugs out before I attempted first start. It started immediately, but also started making these
noises almost immediately.
Thanks for playing! 
Before I tear the engine down this weekend to replace the bearings I thought I would give you a chance to take a guess as to what you think might be
wrong.
So far I have as possible guesses:
1- rod knock
2- spun bearing
2- stuck or bent valve(s)
3- distributor shaft/bearing
4- stuck or faulty vvt timing assy
Steve Graber
http://www.grabercars.com/
"Quickness through lightness"
|
|
|
|
|
MikeRJ
|
| posted on 28/3/08 at 04:17 PM |
|
|
Have you used the old screwdriver tirck to try and pinpoint the location of the noise?
It's too irregular and "sharp" sounding to be a failed big end bearing IME.
Make sure all cam pulleys are tight, I've heard similar noises from pulleys which have been run loose and worn the keyways.
Could also be a broken valve spring perhaps?
|
|
|
jambojeef
|
| posted on 28/3/08 at 04:22 PM |
|
|
Yeah it crossed my mind that it might be a broken valve spring too.
I would whip the rocker cover off before you go any further and watch it running if it doesnt make too much of a mess.
Have you done compression tests on all cylinders yet?
I know nothing about this 4age engine but even something like very badly adjusted valve clearances could cause that type of noise especially as valves
and seats settle after a rebuild.
I wouldnt be rebuilding just yet....
|
|
|
David Jenkins
|
| posted on 28/3/08 at 04:37 PM |
|
|
That's not a pleasant noise...
The noise is arrhythmical - it doesn't seem to happen exactly in time with the engine - so something loose would be my first guess. My first
thought was the same as Mike's - check that the pulleys are properly tight (it's got that sort of sound about it).
In my limited experience, nasty deep-engine noises tend to be exactly in time with the engine. This sounds like something flapping.
|
|
|
oldtimer
|
| posted on 28/3/08 at 04:43 PM |
|
|
Hi, if this is a low mileage Japanese import job, Raw Engineering (info@raw.uk.com...UK(1432)371169)) import them here and say they can sound like a
bag of nails for a while then run smooth. Contact them for advice, but, they say this is not unusual.
Regards
Martin
|
|
|
BenB
|
| posted on 28/3/08 at 04:59 PM |
|
|
Compression test will rule out valve problems so that's job number 1.
After that a mechanics stethoscope can be useful to find out where the noise is coming from...
|
|
|
sgraber
|
| posted on 28/3/08 at 05:14 PM |
|
|
Compression is 150psi on #1 and 120psi on #2,3 and 4 . This seems really low to me.
I have a leakdown tester and will run that test this afternoon.
It is a JDM engine and it'd been sitting in storage since 2003, according to the original purchaser. Bag of nails, yes indeed.
About the arrhythmical nature of the sound. That is the loudest sound. Once I correct that one, I believe there is another sound coming from inside
the engine. Yesterday the internal sound was louder, not the top end sound is louder.
Jenkins, Interesting (great) note about the timing pulleys. I did replace the tensioner and maybe I did something wrong... I will have to go through
this today. Could a loose belt be the issue? A new belt is on order anyways as I had planned to replace this item.
The timing pulleys/tensioner could explain the knocking noise coming from apparently the bottom area around #1 cylinder and the huge valvtrain noise
out by #4?
The noise is so loud that the screwdriver trick doesn't really work too well.
Steve Graber
http://www.grabercars.com/
"Quickness through lightness"
|
|
|
stevebubs
|
| posted on 28/3/08 at 05:28 PM |
|
|
Not an expert, but if it was the bottom end, it would probably still run OK & accelerate (sort of).
If you're having trouble with acceleration then I'd suspect timing issues - i.e. check valves, cam timing etc....
|
|
|
CairB
|
| posted on 28/3/08 at 06:12 PM |
|
|
Steve,
It sounds to me like it could be the VVT. I think on these engines its a vane device. Does it need to be primed with oil?
Colin
|
|
|
triumphdave
|
| posted on 28/3/08 at 07:54 PM |
|
|
It does sound very much like mine did,which turned out to be 2 broken valve springs.
If you always do what you have always done you will always get what you have always got
|
|
|
Mark Allanson
|
| posted on 28/3/08 at 09:12 PM |
|
|
Ever the optimist....
I work in a VAG bodyshop and years ago when we were regularly repairing Golf Mk2's, after a long repair, perhaps a month out of use, the
hydraulic tappets would drain back and would rattle like a good un.
Nothing would cure this except a damn good thrash of about 6-10 miles - cured it every time. Your engine has been laid up for 5 years!
If you can keep you head, whilst all others around you are losing theirs, you are not fully aware of the situation
|
|
|
NS Dev
|
| posted on 28/3/08 at 09:37 PM |
|
|
definitely valve train, but what I don't know!
As others have said, its an irregular noise, bottom end would be like a clock.
I'd also go with the previous comment on followers, but then I don't know the engine at all.
Retro RWD is the way forward...........automotive fabrication, car restoration, sheetmetal work, engine conversion
retro car restoration and tuning
|
|
|
NS Dev
|
| posted on 28/3/08 at 09:38 PM |
|
|
PS I would also avocate the thrash it technique, but don't blame me if it makes it worse!!
On the vauxhall XE engine with drained down followers, the only cure seems to be a lot of revs
Retro RWD is the way forward...........automotive fabrication, car restoration, sheetmetal work, engine conversion
retro car restoration and tuning
|
|
|
sgraber
|
| posted on 28/3/08 at 10:02 PM |
|
|
not hydraulic lifters tho... SHould I still thrash it?
G.
Steve Graber
http://www.grabercars.com/
"Quickness through lightness"
|
|
|
NS Dev
|
| posted on 28/3/08 at 10:04 PM |
|
|
hmmm, maybe not then!!
I really don't know, but the "coming and going" noise sounds like a follower issue.
maybe it is the vvt as you say?
Retro RWD is the way forward...........automotive fabrication, car restoration, sheetmetal work, engine conversion
retro car restoration and tuning
|
|
|
NeilP
|
| posted on 28/3/08 at 10:12 PM |
|
|
Stupid guess but is it possible that a nut has dropped into one of the cylinders? - It would stick in the oil on the piston/cyl wall when cold and
then shake loose on start up and would sound v. irregular - If it is then your bore may be shagged...
Edit: "...Nothing in the combustion chamber..." - Told you it was a stupid suggestion
[Edited on 28/3/2008 by NeilP]
If you pay peanuts...
Mentale, yar? Yar, mentale!
Drive it like you stole it!
|
|
|
CairB
|
| posted on 28/3/08 at 10:33 PM |
|
|
If it is due to air in the vvt mechanish resulting in backlash than it may clear if the solenoid valve is operated one way then the other, which MAY
occur if the vvt solenoid valve is disconnected then reconnected a few times with the engine running.
I would check with othe users of this engine first though to make sure that no problems occur from doing this.
The comments regarding the rattle disappearing after running for a while would tie in with this problem.
Have you had any feedback from the other forums yet?
|
|
|
sgraber
|
| posted on 28/3/08 at 10:50 PM |
|
|
The vvt issue was brought up by 2 other people. But you are the first to explain it so well. I like it. A lot!
Level one:
I will first try to activate the VVT a bunch of times at different rpms, then try the clutch.
Following that I am removing the distributor and replacing with a universal rubberized plug.
Level 2:
I have also bought a new timing belt and will pull the crank pulley, check the tensioner and replace the belt. I'll also check the exhaust
pulley.
I need to check for broken valve springs, but all of my valve clearances were spot on, wouldn't a broken spring show a hecka-large valve to shim
clearance?
I will pull the pan and check for metal particles.
Finally I'll pull the head and do the full monty teardown.
Anything else?
Steve Graber
http://www.grabercars.com/
"Quickness through lightness"
|
|
|
Schrodinger
|
| posted on 28/3/08 at 11:50 PM |
|
|
quote:
Originally posted by sgraber
The vvt issue was brought up by 2 other people. But you are the first to explain it so well. I like it. A lot!
Level one:
I will first try to activate the VVT a bunch of times at different rpms, then try the clutch.
Following that I am removing the distributor and replacing with a universal rubberized plug.
Level 2:
I have also bought a new timing belt and will pull the crank pulley, check the tensioner and replace the belt. I'll also check the exhaust
pulley.
I need to check for broken valve springs, but all of my valve clearances were spot on, wouldn't a broken spring show a hecka-large valve to shim
clearance?
I will pull the pan and check for metal particles.
Finally I'll pull the head and do the full monty teardown.
Anything else?
Yes you could ship the car over here and I will have a look at it for you
[Edited on 28/3/08 by Schrodinger]
Keith
Aviemore
|
|
|
omega 24 v6
|
| posted on 28/3/08 at 11:59 PM |
|
|
No diagnosis YET but are there 2 holes in the exhaust manifold?? If so gun gum them up temporarily and then let us hear it again.
If it looks wrong it probably is wrong.
|
|
|
sgraber
|
| posted on 29/3/08 at 03:38 AM |
|
|
Ok, I think I may have a breakthrough!
I went to put the car in gear after engaging the clutch and there is no drive connection whatsoever to the transmission.
Then I tried to spin a half-shaft with the other end locked and the transmission will not spin at all.
All of a sudden I am thinking that it's not a crazy idea to look into the bellhousing to see if something is broken inside of there. That would
explain a LOT if the clutch disc is broken or some nonsense like that! The clanking noise being some piece banging off the flywheel.
I have never heard of such a thing though and the engine/transaxle did slip together so nicely when I assembled them...
But if there is no connection between the engine and the transaxle and the transaxle is locked up, there may indeed be something going on in there.
I'll follow up with you tomorrow.
Steve Graber
http://www.grabercars.com/
"Quickness through lightness"
|
|
|
ruskino80
|
| posted on 30/3/08 at 04:02 PM |
|
|
no news yet?
|
|
|
sgraber
|
| posted on 30/3/08 at 04:06 PM |
|
|
Argh. I crushed my hand between the engine and the frame rail yesterday pm and stopped working for a bit. I will give it another go today.
I did verify that there is nothing wrong with the clutch nor the flywheel. I still don't know why there was no drive between engine and
transaxle. Maybe when I put it all back together that will be corrected.
I am flailing atm.
G.
|
|
|
sgraber
|
| posted on 3/4/08 at 04:54 PM |
|
|
It's not the clutch. It's not the vvt valve.
Have another listen if you care.
http://www.youtube.com/watch?v=USvb1nx8r90
At this point I am pulling the head and the pan. I want to at least figure out what that damn noise is.
Steve Graber
http://www.grabercars.com/
"Quickness through lightness"
|
|
|
David Jenkins
|
| posted on 3/4/08 at 06:41 PM |
|
|
Hate to say this - but it does sound more like major bearing wear this time around.
If it were my engine, I'd remove the sump and examine the big ends before I ran it again. I would feel happier, even if they proved to be OK.
|
|
|
