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Re: slight bog and run on....

To: 6pack@autox.team.net
Subject: Re: slight bog and run on....
From: Chris Young <pzs83j@ndc.gmeds.com>
Date: Tue, 22 Aug 2000 11:19:46 -0400
Sally or Dick Taylor wrote:

> Chris---The best insurance for NOT having the engine run-on is
> connecting the anti-run-on valve, as when the car was delivered. Short
> of that, reducing the idle speed as low as possible will help, as well
> as not running an air/fuel richer than necessary. I've never found the
> fuel octane to have any influence on engine run-on. An accumulation of
> carbon in the head can add to the run-on. Again, this is a by-product of
> a rich fuel mixture. If the head is new, this should not be part of your
> run-on aggravation.
>
> As you know, high compression makes ignition timing more sensitive to
> advance. It usually shows up as pinging under load. I'm surprised you
> wrote that you hear this, but "not when accelerating." That's generally
> when this sound shows up. That's when it can be reduced by a combination
> of higher octane fuel, and/or retarding ignition timing.  Other things
> can be done, but involves gadgets that you shouldn't have to mess with.
>
>
>
>

Hello all,

In response to the "slight bog and run on" I sent in yesterday.... To
Dick's reply:  Thank you for the insight....I feel the need to clear up the
thrust washer section......I did check the very same way you described, and
had someone push on the clutch pedal.  I detected slightly more play than I
like....(I've had 5 TR6's in the past and several more TR's at the shop
where I used to work)  When I was at Don's we also checked it.  He agreed
that it was more than when "new" but not too bad and can wait until fall.
I was just relaying some of the future plans this fall...At least the list
is getting shorter!!  Since I don't really like doing a job for the heck of
it, I figure I'll check the play in the oil pump while I'm there.
Regarding the bearings, I feel the oil pressure is pretty good (please
respond if anyone feels diff) so I may just leave well enouph alone.

Well, regarding the blow by..It's no where near as much as I thought..
Reason being, I had a slight about of oil coming out of the oil filler cap
on the alloy valve cover...... well, to make a long story short, it turned
out to be a weak gasket used to seal the cap...found another on in my
stash...so far no more leaks. I have the top oiler kit...It throws alot of
oil!!

Regarding the run...Yes, it's true I don't have any sort of pinging when
accelerating.  Just a slight run on when it shuts off.  As stated before,
it runs great all the way up the range....it just has the most annoying
hesitation at 2500 rpm then clears out...  If I do go back to the ant run
on valve I have to figure out how it can fuction without the charcoal
canister....... I repeat, it runs awesome past 2500 to whatever...even if
I'm on the roll and downshift no hesitation....Just when I'm taking off
from a stop......and only sometimes.  I do have oil in the carbs, I may
start experimenting with viscosity, but I doubt anything will come from
it.  Currently I'm using 20W50.

Now here's some thing wierd....I've checked the plugs.  They are leaning
towards looking like a lean mixture with a black ring on the metal (the
threaded portion) of the plug.  The exhaust is dark not overly but dark.  I
have noticed a few black deposits in the rear valence.  Not much but this
tells me it's running rich at some point during acceleration.  Now here's
the kicker...No. 3 spark plug is the darkest.. and looks like it's running
rich...now we all know that 3 and 4 are running of the same carb. (I have
the triple set up)  No. 4 is the same condition as all the others.
Hmmmmm...I'm running Bosch Plat. WR8DP  Prev. I was running NGK BP5ES I
believe. The same thing was happening. The funny thing is the carbs are
still set all the way rich.  No smoke out the rear at idle.  This must be
related to valves or ignition....What are any thoughts?  I going to
sycronize them again.  they were off abit since leaving Don's shop. I
retarded the timing a bit. Cleaned the dark plug. The car ran great for
awhile then started to act up again.  I want to back  off the richness of
the carbs, even though the car seems to not mind it.  Some of the signs
still tell me it's advanced so I may retard some more , what the heck, I
might as well try it....It's easy enouph to put back... Doesn't explain the
one odd plug though.....Any similar conditions out there past or present?
That's what makes all of this fun, eh?

Also, regarding head retorqing......Do people back off and retighten or
just check and tighten as necessary?  All in sequence of course....It's
been awhile so I'm asking......By the way that header puts out a lot of
heat..  I wrapped my starter until I can have the header ceramic
coated!!!!!  Just as Tim H has done...This is something highly recommended
if running a header!!

Chris
74TR6
76TVR
94BMW
93 Ducati


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