> Hey all, seeking advice on why my cam lost a lobe. About 10000 miles ago
> rebult the engine on my 65-66TR4A. The camshaft was reground to the
> factory specs and "parkerized." I installed new lifters , used
> EP assembly
> lube and Isky valve springs. My mechanic friend that helped with the
> rebuild had seen some web chat about lifters being improperly hardened.
> Can anyone direct me to further information on this topic that I may avoid
> the same problem.
I've stashed away several posts from the experts over the years. Most of
them agree that lifter hardness is essential, and that aftermarket lifters
are very suspect in this area. Greg Solow (The Engine Room) says he has
each and every lifter hardness tested, and will not use them if they are
less than Rc 51. Ken Gillanders (British Frame and Engine) offers a kit to
use GT40 lifters (which he says are hard clear through and do not need to be
tested).
Break-in is also essential. Contrary to many other engine builders, those
with TRactor motor experience say to let the engine run at fast idle,
1500-2000 rpm, for 10-15 minutes at first firing. According to Kas Kastner,
this work hardens the face of the camshaft lobes.
Oil selection during first firing appears to be important too. Several have
reported problems from using Mobil 1 (which probably extends to any
synthetic) or Castrol conventional oil. Kas (and others) like Kendall GT-1;
someone else wrote to use Valvoline conventional plus add a 16oz. bottle of
GM E.O.S. Assembly Lubricant #1052367 "provides outstanding protection
against run-in wear and piston scuffing as well as run-in camshaft lobe and
lifter scuffing resulting from insufficient
lubrication."
The only new camshaft I've put in a TR3, I used Valvoline 40 weight racing
oil. I let the engine idle for a few minutes at first with the rocker cover
off, so I could see that all the rockers got oil. Shut it down, let it
cool, retorqued the head nuts and rechecked the valve clearances. Put the
cover on this time, and let it idle some more, first to warm to operating
temperature and then to set the carb mixture, throttle synchronization and
choke synchronization. Then I started driving the car more or less
normally, including some full power pulls to 3500 rpm or so but being
careful never to lug the engine (which I don't usually anyway). Gradually
over the next 500 miles or so, I extended the observed redline out to 5500
rpm. At 500 miles, I changed the oil and filter, retorqued the head nuts
and checked the valve clearances one more time. That was by far the best
running engine I ever had (wish I'd kept the specs for the "3/4 race"
camshaft I got from Beck Arnley) and it was still running fine about 3 years
later when the car was wrecked (and subsequently crushed). Car was no great
loss, but that engine was a real shame. Used to embarrass 289 Mustangs at
the "Friday night drags" (until I broke a tooth in the differential).
Randall
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