Ok, it seems that I have a couple of courses of action. One
is to rip the motor completely apart. I think I'll save that
for last, or at least do it in stages.
Here's what I plan to do, to solve my two problems.
Problem 1: Miss at idle, and basically poor running.
Install new push rods to get my rocker geometry correct which
will solve the problem of my stock pushrods hitting the inside
of the rocker. I've thought through it, and true the pushrod
hitting the inside of the rocker would give me more lift at
the valve as the rocker *ratio* would increase, but not quite
the way I'd like to get more lift. :-) I measured a few of
the cam lobes this AM. They are very close to spec.
.275-.280 are the readings I'm getting. If in fact I've wiped
.005 off a lobe or two already, I should be able to find the
debris in my pan. However, I feel that the readings of .275
*could* be due to my machine shop, or perhaps something else.
OK, so I'm hoping for a miracle. (more on that later) I sure
wish I had measured ALL the lobes before install the cam.
Then I would know. I finding out that patience is an
expensive lesson which I haven't payed off yet.
Once I get the push rods in, and then try running a bit, I'll
know where I stand. I can then debug other systems, ignition,
and carbs, to get better running. I have a gut feeling that
there's a problem in my distrib, but we'll wait and see. I
can't debug other stuff when I know the valves are not being
consistent as they could be.
Problem 2: Low oil pressure at idle (< 25 lbs)
Once the car is warm (normal temp) and has been running for
20-30 minutes, the oil pressure drops. My plan here is to
drop the pan, inspect the cam, measure the end float again.
I'll probably put the .005 thrust washer back the way it was,
and inspect a bearing or two. I should also be able to look
at my cam from the underside. Hopefully I'll be able to get a
hand up there, and feel the cam lobes for pitting. If they
feel good, I'll attempt to get it running this way. If not,
well, you know *that* story.
Many people feel that 10W30 is simply too low of an oil
weight. I know that I'll see lower pressure, but on a engine
with fresh bearings, it shouldn't drop below 25 lbs with hot
oil with 10W30 in my experience. The crank was ground not
more than 20,000 miles ago, and has seen light running. Lower
oil viscosity would make lower pressure, but I'm seeing some
real low readings folks. Before the recent rebuild, oil
pressure was 35 lbs hot, with 10W40 in her. Now I'd say it's
15 or so. There's a problem here, and it ain't oil weight.
I should have my new pushrods today. If not I'll drop the oil
pan tonight to save myself some time. If the new pushrods do
arrive, it's likely they'll need to be made to correct length.
I think it's time for a fine ale, and my blue blanky.
Cheers,
-Scotty '75 TR6 "It was the kind of day when the cap
on the anti-seize wouldn't come off"
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