6pack
[Top] [All Lists]

Re: Cam fixed? p.2

To: 6pack@autox.team.net
Subject: Re: Cam fixed? p.2
From: tr6taylor@webtv.net (Sally or Dick Taylor)
Date: Thu, 26 May 2005 14:19:37 -0700
 Mike----Your cam timing should now be correct, but just one last check
on this. With #11 & 12 valves "on the rock", the timer should also be
pointed right at 0-TDC.  Just having #1 & 2 valves closed is not in
itself close enough.

On to the position of the rotor, when it's about to transfer energy to
the cap.  I like the rotor to be about centered to the (#1 plug)
terminal, with the timing mark at TDC. This is only slightly different
from when the firing event actually occurs with (your) 10 deg. BTDC.
The 'link /spring that pulls your points plate should come out of the
housing by unscrewing it. If you want to shorten this piece, you can cut
off some of the loops  where it screws into the dist. housing. As you
know, this will retard your timing. Then, when advancing the timing back
to where you want it, using the standard method, the rotor will no
longer be able to fire to anywhere but the desired terminal. Ths should
also greatly reduce the burning now seen on the rotor and cap. 
Making the link /spring adjustable is OK.

If you were hearing arcing coming from under the cap when the misfiring
took pace, then doing the above should stop all of that nonsense. If you
didn't hear this, then all you may be doing is reducing the burning you
now see. 
Something else may be causing the msfire. My next bet is that you are
running lean when idling. Unmetered air entering, or needle diameter too
large at the idle station.  Plug coloring is not a valid test, as this
brings in road speeds. (Unless you start with new plugs and only let the
engine idle)

If you want an easy air/fuel test, try hand-choking the carbs to see if
it improves idle. If squeamish about this, lay a shop rag over the air
intake, to richen it up for this test.

If you suspect you're too rich, let some air enter thru a small vacuum
port

Enough, for now?

Dick
 
From:
DaCRANEz@aol.com Date: Thu, May 26, 2005, 4:14pm (PDT+3) To:
tr6taylor@webtv.net Cc: 6pack@autox.team.net Subject: Cam fixed? 

Dick 
Since rebuilding the engine about this time last year I have had issues
with the idle. Recently Vance had a post about how to verify that the
cam timing was correct. I did the check and found that 11 and 12 rockers
were not even. By rocking the crank 16 degrees clockwise I could get
them even with 1 and 2 closed. Called Vance, he agreed that I was
probably off one tooth on the cam gear. Corrected that. Reset cam drive
gear to Bentley specs. I am running 9.5to 1 CR. Premium gas . 400 ft
above sealevel, no anti-run valve, 150 PI cam, Good's 1.65to 1 rockers.
As to the spark exchange I don't hear arcing but the leading tip of the
rotor is a bit discolored and the posts in the cap are a bit burnt. I am
going to try your suggestion on shortening the spring on the retard
capsule. I need a small tap as I am going to install a set screw to make
it adjustable. Sorry about the long tirade last night. I was really
frustrated at not making any headway. GeeZ-I hope this just isn't due to
some bad petrol. Thanks All 
Mike C 




<Prev in Thread] Current Thread [Next in Thread>
  • Re: Cam fixed? p.2, Sally or Dick Taylor <=