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Re: Stag new motor woes



Hello Larry,
	Sorry to hear about the hard knocks ... ;-{

All the following are In My Humble Amateur Opinion, and should not be taken in
any manner that could resemble facts or direct advice:

It sounds like you are progressing in the right direction.  From the posts
earlier from Walter Holliday of Stag Specialists, he noted that he had
experienced some stuck valve problems where the valve would seize in the guide. 
It is very possible for the guide to back out of the head toward the cam.  Valve
clearances would be fine, but a tapping noise will be heard as the guide raises
up toward the top of the valve, growing louder as the guide gets closer to the
spring keepers.  I've seen this on several OHC engines, but it is usually caused
from a deposit on the valve stem, like a big chunk of carbon or burr that pushes
the guide up.  Others suspect it may be from a deposit of gum that forms from
old fuel on the guide wall between the valve stem and guide.

	Your next note, a broken valve spring, could also be a potential problem, but
as you say the clearances are fine.  Since the Stag uses a single spring, a
broken spring will cause a clearance issue and also result in a noticed
performance change.

As to the camshaft journal, I'd measure the clearances on those bearings with
plastigauge before thinking all is okay there.  If the clearances are within a
couple of thousants tolerance, breathe a sigh of relief.  Oil pressure alone is
no indication of oil flow as you have already determined, which is why some do
not recommend an oil pressure gauge.  The oil pressure gage being located at the
discharge of the oil pump just tells you that the oil pump is operating.  This
is why any reputable engine builder will run a wire into every oil passage and
blow it out with high pressure air before reassembly.

Now, what to do about it.  The only way you will be able to get it sorted is:
a.  put things back together and HOPE it was the lubrication problem on the cam;
b.  tear the head down and have a look at the guides and valves;

I suspect that it will be "b", IMHO.

In any case, get a couple of other opinions and advice from some professionals,
then push on.

Regards,
Glenn  Merrell
Triumph Stag Register USA VP
*J*O*I*N**Y*O*U*R**L*O*C*A*L**T*R*I*U*M*P*H**C*L*U*B**T*O*D*A*Y*
*Member of:
*VTR, RMTC, TSC USA, TSR, SOC
*73*S*T*A*G*****************************************************



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