1fz-fe strange rattle at running temp only (1 Viewer)

[ATXnative]

Seems like the timing chain tensioner. at low rpm it would be slapping/rattling a little bit. Not sure how bad it really is for the engine

 

[Somebodyelse5]

Seems like the timing chain tensioner. at low rpm it would be slapping/rattling a little bit. Not sure how bad it really is for the engine

My thought too... the noise *should* change with rpm though? I'm played with it a ton, RPM doesn't change the frequency of the rattle at all.

But, it's probably time to dig in there and swap the chain and put in a ratcheting tensioner anyways... it's on the list

 

[Somebodyelse5]

Just wanted to update everything, here is a video of the noise I was dealing with:


I managed to solve the problem after suspecting it was pre detonation due to carbon build up in the cylinders....

• Ran a full can of MOPAR Combustion Chamber Cleaner (MCCC), with the engine running (and someone helping to keep the engine running). I disconnected the PCV hose from the valve cover and alternated spraying the MCCC and plugging the hose with my thumb. Your rpms will drop suddenly and the engine will want to die if you leave the hose unplugged too long. Followed the instructions on the can... warm up, spray in full can, run for another 10 minutes. This stuff does not smoke nearly as much as Seafoam does
• I removed all the spark plugs, looked like they had a bit of carbon fouling, most of them measured ~.040" gap (one was at ~.025")
• I sprayed most of another can of MCCC into each of the cylinders, put the plugs back in loose, and let it soak the head of the cylinders for 24 hours
• I rigged up a small hose attachment for my shop vac and sucked out all the schmoo, looked like cookies and cream coming through
• I sprayed carb cleaner and let that soak for about an hour and then spent a long time spraying and using the shop vac until what was coming out was relatively clean
• New plugs gapped to .031", new ignition cables, and new distributor cap
• Started up, got to temp, and let the crud burn off (not nearly as Smokey as you'd expect)
• I then checked the timing with a timing light per FSM (it was about 15deg BTDC.. which is WAY too advanced). I bumped it back to 3* here is an OTRAMM Video:
• Definitely should change your oil after you do this

After that, I'd say the issue is 95% solved. Does it a tiny bit if I rev it up from idle, in neutral, but not nearly as bad as in my video. I'm attributing that to the carbon that still remains in the cylinders.

Here are some pictures, as best as I could get using my cheapo bore scope.

After one can of MCCC:

Cylinder after 24 hours of soak (I was unable to get clear pictures after the carb cleaner went in, no matter how much time I spent with the vacuum):

 

[Somebodyelse5]

Another of of a different cylinder:

Spark plug #6:

Vacuum attachment:

And in use:

 

[Vasiliy]

glad to see you fixed that. I was waiting for your feedback result, 1FZ Experts - I've got a noise! - https://forum.ih8mud.com/threads/1fz-experts-ive-got-a-noise.1207069/
since mine the same. Now obviously I know what I need to do next spring

 

[Somebodyelse5]

glad to see you fixed that. I was waiting for your feedback result, 1FZ Experts - I've got a noise! - https://forum.ih8mud.com/threads/1fz-experts-ive-got-a-noise.1207069/
since mine the same. Now obviously I know what I need to do next spring

I forgot i had that thread! I’ll post this up there as well