What is this engine noise?

ninja jt

LVC Member
Joined
Sep 16, 2017
Messages
26
Reaction score
2
Location
Northern IL
Anyone know what this noise is? All of the chains and tensioners were just replaced. Everything seems to run smooth, idles great, drives fine, but the noise is there even with the belt off so it doesn't seem to be any of the belt driven accessories. I would say it sounds related to engine speed, but only a fraction of the RPM. Also slightly louder under the car than above.


Belt on
Dropbox - WITH BELT.mp4

Belt Removed
Dropbox - NO BELT.mp4

Car warmed up after short drive
Dropbox - WARMED UP.mp4
 
I am guessing due to experience witha 2.4 gm dohc I work on the chain tensioner may be not pushing full out to take up slack in the motor and causing a noise. Also mine is hydraulic running out with engine oil and a spring. Mine let go and 4 cylinder made noise due to allowing chain slack
 
Last edited:
Anyone know what this noise is? All of the chains and tensioners were just replaced. Everything seems to run smooth, idles great, drives fine, but the noise is there even with the belt off so it doesn't seem to be any of the belt driven accessories. I would say it sounds related to engine speed, but only a fraction of the RPM. Also slightly louder under the car than above.


Belt on
Dropbox - WITH BELT.mp4
With a new tensioner, it has to be pumped up with engine oil thru a small hole in the back of some car for it to take up the slack in the chain. Why don't you write back with up dates as this foumn is a 2 way street, not one way only
Belt Removed
Dropbox - NO BELT.mp4

Car warmed up after short drive
Dropbox - WARMED UP.mp4
 
Well I believe I figured out the issue. Looks like the crank seal got pushed too far back into the timing chain and never really sealed around the harmonic balancer. This led to a tiny bit of oil to cone out. Just enough to see some wet areas, but never enough to leave a drop on the floor.

So I bought a new seal and tried putting this one on the balancer then installing the balancer, but it won't seat fully in the timing cover. I pulled the balancer again and tried installing it in the cover and putting the balancer back on, once again it pushed the seal back into the timing chain. Luckily I could tell that it was too far back from using a scope.

Now I'm stumped. There's no way to stop the seal in the timing cover and no way to stop the seal from sliding further on the balancer. Those of you that have done the timing chains, or replaced this seal for any other reason, what's the trick? I've thought about trying to make a shim that I can then pull out after the balancer gets installed, but I'd rather not.

20180127_123228.jpg


20180127_123234.jpg
 
That's part 2W9Z-6700-AA ?
The few front seals that I have replaced (not on an LS) had a metal lip that prevented them from being pushed too far into the engine. That doesn't appear to be the case here. The service manual instructions are the same as most though. You may have to search some Jaguar 4.2 forums.

Installation

  1. NOTE: Lubricate the crankshaft front oil seal and the engine front cover mating surface with clean engine oil.

    Using the special tool, install a new crankshaft front seal.

  • s6x~us~en~file=a0083730.gif~gen~ref.gif
  1. Install the crankshaft pulley. For additional information, refer to Crankshaft Pulley in this section.


 
I ordered it through Christopher's foreign parts, same place as all the parts/seals for the timing chain replacement.
I did lube the area and I almost think it made it worse and allowed it to slide more. If there was a lip on the seal it would be so much easier.
Good thinking on the 4.2 forums, I'll check that out, thanks!

On another note, I tried a strap wrench and ended up breaking the belt . Now I have a 4' section of unistrut that I bolt up to the balancer and wedge on the floor when I need to torque the bolt or loosen it.

20171030_210745.jpg


20171103_201911.jpg


20171103_201907.jpg
 
I hope that much damage was done by removing the seal after install.

If not... I have a few thoughts. Anything I say at this point... is not meant to insult your intelligence,,, But me just "checking off all the boxes" since I don't know how much experience you have.

First... I assume you checked the "slip fit" of the seal on the back of the balancer,,, to make sure the seal wasn't too snug? It shouldn't be a force fit,,, but instead slide on freely with a slight resistance.

Second... The black, (flat side), of the seal was installed facing the balancer?

Third... if you didn't use some sort of tool to install the seal,,, but instead tapped the seal in around, (circular manner), the crankshaft snout with a hammer,,, this can sometimes tweak/twist a seal enough to oval/egg the inner diameter of the seal enough to damage the seal and "catch" when installing the balancer.

Fourth... sometimes seals need a little "glue" to hold them in place. Indian Head cement, (shellac), or something similar might help, (allowing for dry time). Also... a little "assembly lube", or oil... or grease on the inner lip of the seal reduces friction. Most seals aren't installed "dry".

Fifth... I haven't yet had the priviledge of pulling the front cover on my LS... but if it doesn't use dowel pins for alignment, (or there is some slop between them and the front cover),,, the hole for the seal may not be concentric with the snout of the crankshaft. Keep in mind that even 1/32 of an inch, (a little over 30 thousandths), .031+, could be enough to catch and bind on the edge of the seal while installing the balancer.

Not knowing any details... my best guess would be #3 or #5.

So I bought a new seal and tried putting this one on the balancer then installing the balancer, but it won't seat fully in the timing cover.

This is because there is a "step" on the crankshaft... preventing the balancer from going back too far... plus the back of the balancer isn't meant to run right up against the face of the seal.

Hope this helps... and that I haven't insulted you.
 
Nope no insults here, I appreciate all of the feedback. I'll admit the first time I did not check the slip fit and that was a big part of the mistake resulting in that shredded seal. I did check it on the new seal and I would say it's more snug than a traditional slip fit, but I didn't have to use much force to get it on. It's snug enough that I would expect it to seal well.
Yes the flat was towards the balancer.
I didn't think about three and it's definately a possibility.
Every time I lubed the outside it got me in trouble, I left it dry the last time to let the rubber grab the ID of the cover and it worked. Lubed the ID of the seal so the balancer would slide in and everything seems to be in place.
Your last item about the concentricity of the shaft to the seal I didn't think about, but after looking at it more I know that it was part of the problem.

I don't think there's a step on the crank, I think the balancer just meets up with the timing gears. Unless you meant behind the gears?

20171122_214429.jpg
 
Depending on the engine manufacturer and design,,, the lower gear can either slide on the snout back to the step... or slide on the step back to the face of the first journal. Either way... the lower gear is "sandwiched" behind the balancer.

In this case the "step" (down), starts at the face of the oil pump. So yes... it's behind the lower gear. That's why you didn't notice one.
 

Members online

No members online now.
Back
Top