Ticks! The HLA noise that won't go away.

[OwnerCS]

I just want to bring this thread to conclusion. I think the tick issue is soon to be resolved.

As it turns out, one of the best VH45DE mechanics in the state and possibly in the central US is literally down the street -- no kidding. My son struck up a conversation with the shop owner over another white 91 Q that was in for repairs and learns the top shelf mechanic grew up at the Infiniti dealership from the time when the cars were introduced. So then I take the car there to get his opinion and he nails it in less than an hour. He listens to the car, pulls the left bank VC and quickly determines the left bank chain tensioner is running without oil. The ticking noise is from the chain slapping the top guide -- the one under the VC. So to make a long story short, he said it is a common mistake for a new mechanic that is unfamiliar with RTV to use too much on the front chain cover that results in an oil passage being blocked. I guess one of my earliest suspicions turned out to be true. I'll know more tomorrow.

Here's my plan below.. The cleaner won't go to waste as other cars can use it..

I've been trying to map out a scenario in my mind for a chain tensioner contributing (or being the root cause) of the noise.

I have a concern about an oil channel in the timing chain cover, the one that runs alongside the channel for RTV, being obstructed. If some RTV from the outer edge oozed over into the oil channel on installation, it could obstruct the flow. If that oil channel provides lubricant to the upper chain tensioner, could the upper tensioner be noisy from oil starvation?

[maxnix]

Off with the timing chain covers? I thought your original misdiagnosis was at fault. Keep us update.

[OwnerCS]

It runs really quiet now.. It sounds like a new engine purring..

Some RTV had clogged the oil passage to the left bank tensioner.. Removing the tensioner and cleaning the oil port took care of the problem.. I'm glad that I didn't drive it enough or race the engine to do any damage..

As it was explained to me, if the chain tensioners fail to function, the excess slack will allow the chain to slap the head guide (far left in the following picture) to make a tapping noise to sound an alert that something is going wrong inside the engine -- hopefully before the chain jumps -- and you all know the rest of that story..

[Infinitiguy19]

Glad to hear its fixed without major work. This is the first time I have heard of this but I wonder how many times this has happend to shops that do this work?

Whats also weird is before you came on there used to be a user called Unknown007 who did some plenum work and maybe some valve cover work as well. He had a ticking noise after he put it all back together which he could not trace. But his car sat for months till he finished the work.