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Re: TR4 - Engine Noise Problem Found

To: "Triumphs" <triumphs@Autox.Team.Net>
Subject: Re: TR4 - Engine Noise Problem Found
From: "Brian Sanborn" <sanborn@net1plus.com>
Date: Wed, 26 Aug 1998 20:41:40 -0400charset="iso-8859-1"
Well the cigar and what's behind curtain number 3 goes to Michael Porter!!!

As he suggested, I retarded the timing a little and the noise was harder to
bring on.  I then dialed it back to 0 degrees and took of the off the vacuum
advance line and bingo.... I could drive really aggressively without a
noise.  If I really put it to the floor and cranked it up,  I could start
the noise up a little.

I NEED TO  GO BACK TO TIMING SCHOOL

When I first did the points and plugs I set the timing statically and
twisted in the turns for advance.  Then hooked up the timing light and saw
the timing mark about and 1 - 1 1/4 inch to the right of the pointer.  The
car ran great.  Since I retarded back to no advance... the engine runs
fine.. sounds a little different.... but pulls strong without the vacuum
advance connected.  I can't believe that the engine should be that tolerant
of the vast differences in timing.  I did get some afterrun when I turned
off the key after a drive in the retarded setting.

Don't forget from previous post that the distributor is installed off one
tooth to the counter clockwise direction.  I don't think this should effect
timing as long as it is turned to the 7:30 position... really don't know.  I
will correct on Saturday.

I found something else... I found a cork in the intake manifold fitting for
the PCV valve.  Removed and the engine idle increased and I adjusted it back
down.  Would this have created abnormal vacuum pressures?

What are the recommendations... buy a new Mallory distributor.  Rebuild the
current one.  Or learn how to time the engine correctly

Thanks to all you guys that helped with the diagnosis


Brian Sanborn
62 TR4          CT16260L  - Groton,  MA
sanborn@net1plus.com
-----Original Message-----
From: Michael D. Porter <mdporter@rt66.com>
To: sanborn@net1plus.com <sanborn@net1plus.com>
Date: Wednesday, August 26, 1998 4:22 AM
Subject: Re: TR4 - Engine Noise Problem(long)


>sanborn@net1plus.com wrote:
>
>when I give it lots of gas pedal I hear a loud banging noise that sounds
>like the hood "prop up" rod rattling on the wheel well or something like
>that.  There is some added vibration that goes with the added power, but
>not unusual.  The noise is not the bearing noise I have heard before in
>my life, which sounds like the muted sound of a hammer on a big anvil.
>
>The car's timing is probably off by a mile with the sloppy distributor.
>This description is precisely that of severe pre-ignition or possibly
>detonation. Way, way too much advance for the load placed on it. If it
>goes through the same rpm range without the noise on very light
>throttle, or the noise diminishes after retarding the static timing,
>that's your answer.
>
>Cheers.
>


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