[TR] TR4A - Is this noise detonation

[Randall Zempel]

Guy,


That doesn't sound like detonation to me...it sounds more like timing chain
slap, or maybe a shot waterpump or even loose fan blades.  I understand
you've replaced the timing chain and tensioner, so I dunno.  That's just
what it sounds like to me.

Randall Z



Message: 8
Date: Fri, 20 Apr 2012 12:34:52 -0500
From: "G.D. Huggins" <guy at genfiniti.com>
To: triumphs at autox.team.net
Subject: [TR] TR4A - Is this noise detonation (link provided to
       listen)
Message-ID: <3916E272-D733-48A4-B605-881D6D3A97D3 at genfiniti.com>
Content-Type: text/plain; charset=us-ascii

All,

In order to help you help me, I made a recording of the engine with a
quality
microphone and posted to YouTube (link below).
In addition to the normal tappet and valve noise we should hear in the
engine,
I have this mysterious "rattle" that seems to correspond to the advance
kicking on or off.
Randall suggested it might be detonation, but I have no idea what the hell
detonation sounds like.
Could you please watch/listen to the video and discern what the noise is?
(Detonation, other)


http://www.youtube.com/watch?v=Rf2qpLHv9IM


The following comments are related to the video:

After start-up, the rattle is spotty when idling
When I move to fast idle, it greatly diminishes
When I give it real throttle, the rattle is super loud and present
When I come down it diminishes, but suddenly spikes (second 32), which I
believe is when the advance cuts out





Cheers,

Guy D. Huggins
1965 Triumph TR4A
CTC 63569LO