[TR] TR6 rocker assembly oiling

Randall tr3driver at ca.rr.com
Wed Mar 26 09:42:32 MST 2008


> Then I read 
> Randall's parting comments "I'd probably try that again, even 
> though it eventually cost me a broken piston last time I 
> tried it." ACK! Randall, you should be a novelist with 
> cliffhangers like that! Can you elaborate just a bit???

Apologies, Brian, thought I'd told this story enough.  Years ago, I bought a
56 TR3 sight-unseen, just to get the overdrive.  When time came to swap the
OD into my 59, I swapped the engine as well, since it seemed healthier.  But
I soon discovered there was no oil flow to the rocker shaft; apparently the
rear cam bearing had been installed wrong.  So I installed the external oil
feed.

This put HUGE amounts of oil into the rocker shaft; so much pressure that it
literally sprayed oil all over the underside of the hood the first time I
started the engine.  Even with the cover on, it leaked all over (including
out the filler vents and past the hold-down nuts).  Then of course I
discovered that the valve guides were well worn, and now they sucked lots
and lots of oil ... like driving a mosquito fogger !  I literally got cited
for excess smoke.  Tried installing a restriction to the flow, but never
could get it down to original levels.

So, yet another Band-Aid, I installed intake valve seals.  Worked well for
awhile, but somehow one of the seals came apart, resulting in only that
cylinder burning oil.  

Apparently, the excess oil was causing spark knock under cruise conditions
(oil has a very negative effect on octane) but I didn't realize it (couldn't
hear the knock over the wind and general mechanical noise) until the
cylinder quit running.  When I pulled it apart, I found that the piston
lands had been broken away from the piston by the knocking.

Coda :

Still didn't have time or money for a proper rebuild, so I threw the bypass
away, got the head done (with new guides) and ran a drill down through the
passage into the rear cam bearing.  With every intention of only driving
that short block for a year, until I could accumulate enough money to
rebuild the original engine.  Never did happen; that 56 short block is still
in the car today.

No, I most emphatically do NOT recommend that anyone else fix their
improperly installed bearing by drilling through it !  I got away with it
once, only because I didn't care if it ruined the rest of the motor ...
likely I wouldn't be so lucky a second time.

Randall


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