Rattle in Head

ncgoblin

Goblin Guru
Hey all,

Bare with me some backstory. Last year I had an engine that failed but right before it did I installed a timing chain kit by coyles with the new style tensioner due to a rattle. Since the timing set was fairly new when it failed (believe head gasket) I moved all the parts over to a spare engine which has been running great for 4 months. Recently I replaced a rear main seal and NGK plugs and installed the engine. Last night while driving that same timing chain rattle came back but on this spare engine! The engine also takes about 4-5 seconds to start after priming the engine but idles completely fine. Oil pressure is 50-70psi and at full on the oil stick. What are the odds I have a faulty tensioner? Before I remove the chain and inspect I am wondering if I may be missing something.

Thanks
 

Desert Sasqwatch

Goblin Guru
As many here on the forum have had bad to disasterous experiences with timing chain failures - some of whom will most likely chime in once they find this thread - the noise is most likely a bad sign. Don't take chances with this engine, order the timing set AND the correct bolt and get this one fixed! :)
 

OptimizePrime

Goblin Guru
Looking at the timing chain side, top right. Do you have the upgraded bolt that threads into the cover and replaces the shouldered bolt that's holding the plastic guide there?

The stock shouldered bolt in this position is notorious for breaking and the guide will be loose and create slack (or even break off). Check here first before diving in
12273
 
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Ark :D

Goblin Guru
As many here on the forum have had bad to disasterous experiences with timing chain failures - some of whom will most likely chime in once they find this thread - the noise is most likely a bad sign. Don't take chances with this engine, order the timing set AND the correct bolt and get this one fixed! :)
/nod
 

ncgoblin

Goblin Guru
I have about 500 miles on this timing set from cloyles which includes the upgraded tensioner, new guides, and I purchased the upgraded guide bolt that is solid metal all the way through to the guide.

I’m reaching out to cloyles maybe my tensioner is not getting pressure?
 

ncgoblin

Goblin Guru
So I have some bad news the timing chain / tensioner replacement did not help I was not surprised to be honest but it only cost me labor so worth a try. When the LSJ idles after being warmed up its at 25PSI. I drove around the neighborhood about 25mph and it went up to 50PSI. It then idled at about 30PSI in the garage. This seems a bit low for pressure and am wondering if this is a contributing factor when I accelerate and hear the loud rattle. I never hear the rattle at idle in fact the engine sounds fine.

This is a similar sound I heard right before my old engine gave out I have yet to tear it down since I had a spair kicking around which is now installed.

My oil pressure gauge is coming off of the oil cooler. I did some research and it looks like the oil pump is built into the timing chain cover is this correct? What are your thoughts on the oil pressure? Is there a place I can install a manual pressure sensor on the head is it worth the effort?

Another concern I found is all spark plug holes were polished except for Cylinder #2 which had a lot of black coating thought this was odd.

I apologize for the questions I am running out of answers to this odd issue.
 

OptimizePrime

Goblin Guru
Leakdown test #2 cylinder?

Stock cams? I would assume your tune is not optimized for upgraded or VVC. Is it possible for the piston to hit the valves in these motors (valve overlap)?
 

Desert Sasqwatch

Goblin Guru
I wonder if there is an issue with the VVT cam timing mechanism? I'm not sure how to get this checked, but I'm sure there is something on YouTube.
 

ncgoblin

Goblin Guru
This engine can gears are not VVT phasers I believe this is what you are mentioning. The entire head is OEM that I know of.
 

DCMoney

Goblin Guru
Black coating around the spark plug is probably a leaking spark plug seal on the valve cover. See pic below of all the valve cover gaskets.



Sound like a bad cam chain tensioner, which video or thread did you follow when installing the timing chain kit?
 

Torchandregdoc

Goblin Guru
My oil pressure gauge is coming off of the oil cooler. I did some research and it looks like the oil pump is built into the timing chain cover is this correct?
This is correct. The oil pump is built into the timing chain cover, directly behind the harmonic balancer.

To me, it doesn't sound like your oil pressure is that low. 50-70? Right?
 

ncgoblin

Goblin Guru
Black coating around the spark plug is probably a leaking spark plug seal on the valve cover. See pic below of all the valve cover gaskets.



Sound like a bad cam chain tensioner, which video or thread did you follow when installing the timing chain kit?
I followed the coyles timing chain install for the LSJ YouTube the upper tensioner has been replaced. I am going to check compression today.
 

Lonny

Administrator
Staff member
Next time you run it try to record some audio and post it. Maybe somebody will be able to identify the problem from hearing it.
 

DCMoney

Goblin Guru
Like Lonny said a video of the noise could be helpful.

Is your engine stock? Tune stock? Could you be hearing spark knock? Do you have HP tuners or something similar to monitor your engine?
 

Lonny

Administrator
Staff member
Pull your belt off and run it again. It may not run very well. It might help to pull the MAF plug while doing the test.

This will eliminate a lot of spinning stuff. When you get your belt off tug and twist around on your engine pulley to make sure it's not cracked.

Check around your exhaust to make sure it's not self destructing and going crazy when the exhaust pulses get just right.

It kinda sounds like it has piston rattle, I wonder if it has ever been over heated. Hot enough that the position skirts collapsed enough that the pistons can rattle against the cylinders.

It could also be a rod knocking. You might want to pull the oil filter and check for metal.
 

ncgoblin

Goblin Guru
After removing the serpentine belt sound is still there I also put the stethoscope up to the supercharger and heard some similar noise but this may be an echo affect since the serpentine belt is off. I know this sounds like faulty chain but it’s been replaced along with gears and tensioner for those that have not seen previous post.
 
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