[TR] Mystery Smoke Update

[Alex]

Thanks Randall............ a lot to check this weekend...good things it's a 
long weekend.


----- Original Message ----- 
From: "Randall" <TR3driver at ca.rr.com>
To: "'*Triumphs List'" <triumphs at autox.team.net>
Sent: Tuesday, November 22, 2011 3:31 PM
Subject: Re: [TR] Mystery Smoke Update


> Alex,
>
> IMO your first problem is to figure out what is going on with the carbs.
> You should not need to change the needle in order to get them as lean as 
> you
> like at idle.  If that is not the case, then you have a leak inside the
> carbs (leaking fuel into the throat) or badly worn jets/needles, or some
> other problem.
>
> Worn jets are a particularly nasty problem, since they change the mixture
> calibration curve.  If you adjust the mixture at idle to compensate for 
> the
> wear, then the mixture will go lean under cruise conditions, which can 
> lead
> to overheating and potentially severe engine damage.  I believe worn jets
> were the "root cause" for my Dad's TR3A swallowing a valve many years ago.
>
> Then you need to address whatever is wrong with #4.  Sounds like you may
> already have a burned valve, possibly due to the carb problem.  Last time 
> I
> had a cylinder that only did 60 psi cold, the valve head looked like 
> someone
> had taken a slice of pie out of it.
>
> To answer some of your questions, yes, it's fairly easy to drop the pan 
> with
> the engine in the car.  No need to remove the clutch slave, just back off
> the nuts on the support rod so you can remove the bolt through the pan and
> swing the rod out of the way.  Lower the pan slowly, so you can maneuver 
> it
> around the oil pump screen without breaking the screen.  (However, the
> screen may be already broken.)
>
> If you suspect a leaking head gasket, it might be worth doing a check for
> combustion gases in the coolant before starting to disassemble.  I have 
> seen
> several cases where the gasket was not obviously "blown", but was leaking
> enough to cause problems.
>
> Note that the pan bolts are not all the same length (or at least shouldn't
> be).  The short one goes in the front, the two long ones go at the left 
> rear
> (one for the road draft tube brace, the other for the clutch slave brace).
> On my TR3, I found that some DPO had changed almost all of them to the 
> wrong
> length, and the threads in the front hole were damaged as a result.
>
> -- Randall