Guys,
Thanks for the interesting comments. Regarding the related comments of
Larry and Steve, I believe the quite long service I got out of the BF45s
indicates that oil consumption is not a big problem with this motor, as
long as I'm using hot enough plugs. The BF124s are evidently very COLD
plugs. I'm sure they had less the 5k miles before I replaced them, and even
less before they started showing a problem. I would mention that I have
molybdenum alloy piston rings (top only) in this engine. In my previous
rebuild I used two moly rings per piston. That engine never did quit using
oil - about a quart every 500-1,000 miles. When I took the engine apart, to
my great surprise I discovered that the first two rings on every piston had
the gaps lined up. Since I was very careful when I assembled it to place
the gaps as suggested in "How to Rebuild Your Small Block Ford", I have no
idea how they decided to line themselves up. In talking to various
"experts", most seemed to think it really didn't matter how you installed
the rings, because they would move around in use anyway. However, that
experience, plus previous of my own and others I know that have installed
moly rings, seem to indicate that getting moly rings to seal is a common
problem. So, the last rebuild I used one moly and one plain iron ring.
Depending on the oil I use and other factors, I now get about 1,500 - 2,000
miles per quart oil consumption, although it took awhile for it to get this
good. I believe this oil use is still primarily oil getting by the rings,
not down the valve guides, but this is a an assumption based on my previous
moly ring experience and the fact that the oil use has steadily declined
over the approximately 35k miles on this rebuild.
My assumption is that the two cylinders that had the carboned up plugs
still using a little more oil because the moly rings are not yet fully
sealed. But once the carbon buildup begins, it probably goes from bad to
worse very quickly, once they start misfiring.
Regarding Chris' endorsement of the Bosch Plus 4s, I like the fact that
they are unshrouded and indexing would be a moot point as well. But can you
set the gaps? (you would have to set four per plug!) I may give them a try
next time though. What was the part number for the ones you used in the
Tiger ('65 Mustang application)?
At 10:14 AM 10/31/99 -0500, twojohnsons@home.com wrote:
>I vote for standard Bosch Platinums. Used in all my cars. Never had a
>problem, and
>they seem to last forever.
>Al J.
At 09:55 AM 10/31/99 -0500, Larry Paulick wrote:
>Bob, how many miles are you getting on these various plugs? Sounds like
>you are changing them quite often, and if so I wonder why?
>
>Maybe something else amiss, no pun intended.
>
>Larry
At 06:26 PM 10/30/99 -1000, Chris (in Hawaii) wrote:
>I run the Bosch plus 4's in my camero, chevy 4x4, and saturn. I have not
>tried them in my tiger since the engine is still on the stand but it has
>plus 4's in it. you can really tell the difference. i do not know which
>ones would work best for you though. i just got a set of 65 mustang ones
>for the tiger. i also put them in my moms astro van and ranger, she had to
>buy new tires for the ranger in a week. try the fancy plus fours and you
>will be happy!!
>Chris ( in Hawaii)
At 07:40 AM 10/31/99 -0500, Steve Griffing wrote:
>, perhaps 15-20k miles or so
>
>That's pretty good!
>
> > Today I pulled the plugs. Some looked very clean, some looked so-so, and
> > two looked pretty carboned up
> >I ran a compression check just to be sure. Yep, 190-200 lbs/in on each
>cylinder
>
>You might want to check the seals on those two Intake valves. Just a
>thought.
>
>Happy motoring and thanks for the info'.
>
>Steve.....aka bartdog@mindspring.com
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