Brian Sanborn wrote:
> >after starting at 0 degrees the car will idle best when set around 40
> >degrees advanced!
>
> >If the timing is off because the cam and i shouldnt worry about what the
> >pointer indicates, why wont it start that way?
> >it seems to be firing on the upstroke at 40 so it wont even crank more than
> >once.
>
> David,
>
> I read Paul Buur's reply and I think he has the right problem identified. I
>just rebuilt my TR4 engine... but I am no expert. So the following is just my
>humble opinion.
>
> The 40 degrees advance to run smooth and the firing on the up stroke during
>starting just are not normal. The car should run fine with 4 degrees of of
>advance. It should also run acceptabily at -4 degrees retarded for that
>matter. Getting a new cam and timing gears lined up right is a very difficult
>operation at best.... at least the first time. I spent a couple of days
>trying to get this right. I tried the degree wheel idea and gave up from
>ingnorance.
>
> I did successfully use the the technique documented in the Haynes and TR
>workshop maunual where you set the timing based on the position of #1 cylinder
>and the valve opening on #4 cylinder. That procedure is very tedious but does
>work. Also cheated a little by lightly transfering the timing marks from the
>old timings gears to the new gears. The workshop procedure led me straight to
>the position where those "cheater" marks lined up.
>
> If the cam timing is found to be correct then the only other thing that comes
>to mind is that the distributor might be installed a tooth or two off.
>
> Good luck... hope you sort it out successfully. Let us know what happens.
>
> Brian Sanborn
> '62 TR4 CT16260 Groton,MA
> TR4 Website www.net1plus.com/users/sanborn/home.html
David,
Before you go pulling the cam suspecting it is not timed correctly (although I
too think this might be the problem) take a few minutes to actually confirm
that the mark (hole) on the crank pulley really does conform to piston TDC.
The early two piece pulley can be bolted to the hub wrong, steering you in the
wrong direction. I say my suspicion is the cam timing because bolting the
pulley up wrong would be an error of 60 degrees, not 40 - but you never know.
Check TDC easily by pulling all the plugs, putting the car in 4th gear and
slowly pushing the car forward while keeping your finger over the #1 spark plug
hole. Stop pushing when you feel/hear air rushing out around your finger.
That means you're coming up on the compression stroke. Next take a very thin
screwdriver and insert it into the spark plug hole - not too deep, just about
2" into the hole. Now continue slowly pushing the car forward to turn the
engine. Gently apply upward pressure on the screwdriver and twist it slightly
to make sure it isn't binding as the piston comes up - if it binds, stop
pushing and withdrawal the screwdriver a little until it frees up again. As
the piston comes up, it will contact the tip of the screwdriver and rock the
handle end you're holding downward. When the handle is at it's down-most
point, just before it starts to lever upward, you have found true TDC without
having to make any special tools or disassemble any major components. Now look
at the timing mark on the pulley and see if it lines up. If it does, then your
problem is almost certainly the cam timing. If the mark doesn't line up, file
a small notch in the edge of the pulley and mark the new TDC notch with a
little white paint.
Good luck!
Regards,
Brian Schlorff '61 TR-4 '64 TR-4 '72 TR-6 '79 Spit
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