Andy,
How frustrating for you!
I would set the timing at 4 degrees BTDC static timing. That's close
enough and is the starting point for that. Set it and leave it for now,
and be sure that all plugs are firing. If you have a strobe flash timing
light, don't use it on TD for timing, but it's a good tool to test
sparkplug operation by clipping onto each wire in turn and watching for
regular, strong flashing.
Colourtune may be giving you misleading readings of the mixture. On
the chemical brew we get in CT, sold as gasoline, you need to adjust the
mix so that Colourtune is to the rich side of the ideal "bunsen blue"
color. That BB color is (or was) fine when the Colourtune was developed
but is not the color you want with the fuel available in CT and New
England. Hal Kramer wrote up some good material on this three or four
years ago for the GOF in Plymouth.
Have you had opportunity to measure the movement of the
pushrod/rockers? I am beginning to wonder if another pushrod is bent, or
if a cam lobe or two has been ground off by the bad tappets.
Can anyone tell Andy how to identify his camshaft by measuring
opening---somewhere I read about setting gap to .055 and taking
measuremnts, but I can't find that info now that I would like to share it
with him.
Seems to me that he needs to know what camshaft is in the engine so
that he can set clearances to that camshaft.
Bob
On Fri, 2 Nov 2001 20:06:30 -0500 (EST) Andrew Moyce <amoyce@pol.net>
writes:
> My engine blues continue and I'm in danger of enlisting the aid of a
> professional mechanic.
>
> Brief review and present status:
> 52 TD, engine completely rebuilt 18,000 miles ago
> Gradually developed noisy tappet, which seemed to increase after
> recent 500 mile trip . . . no performance problems.
> Checked tappets, and found significant wear, with pitting in those
> for cylinders 1 and 4,. Also found the head of one of the pushrods
> had broken loose from the shaft, riding up and down in the hollow of
>
> the shaft.
> Replaced all tappets and offending pushrod. Can't be sure of cam
> specs (reground or replaced . . . I don't remember which). Set the
> valves at .013 cold, then readjusted to .012 warm.
> Test drive about 20 miles . . . tappet noise gone, good performance
> until about 10 blocks from home . . . lost power, uneven
> running . . . limped home.
> Checked spark plugs, all normal color.
> Checked compression (1st time since rebuild) 2 and 3 cylinders 150,
> 1
> and 4 low at 120 and 125 respectively. Squirted oil into 1 and 4,
> compression came up to 180 and 155.
> Reset the valves at .020 cold, .019 warm. Tappet noise is back . . .
>
> seems to run better but still not at full power (3d gear hill now
> needs 2nd gear, can't keep freeway speeds on gentle uphills.)
> Pertronix ignition, nothing to check.
> Carbs by Colortune unchanged (front runs a little rich)
> Timing unchanged. Tried retarding 10degrees. . . seems to even out
> idle, maybe runs a little better, but now transmission rattles.
> Reset valves to .016 (compromise). Noise is gone, performance about
> the same.
>
> I don't know what else to do.
>
> Andy
> 52 TD, limping
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