From: Chris Reinhardt <[EMAIL PROTECTED]>
Reply-To: [email protected]
To: [email protected]
Subject: Re: [F500] Melted 494 piston question
Date: Sun, 27 Aug 2006 20:09:58 -0700 (PDT)
Lean would definitely reflect on EGT's but you have to learn you gauge
and location of the probe, everyone is different. The high water temps
would have made the lean condition worse, because now you have a lean
motor working harder because everything is now tighter.
CR
Kenneth Kirkland <[EMAIL PROTECTED]> wrote:
Guys,
Would a lethal lean condition have been reflected in
high EGT readings? I run a little rich for some
insurance and was getting readings of ~1080 F. that
day on the cylinder with the plug deposits.
Since I lost 3 quarts of coolant to the leak during
the race, my initial reaction was to blame it on high
water temp.
Is there a particularly good way to flush a crankcase?
Thanks for all of the excellent information,
Kenneth
--- Richard Schmidt wrote:
> Chris,
>
> You are correct. Unless Ken messed with the timing,
> my guess is that it is
> just a lean situation.
>
> Also, I did forget to mention the "clean the
> crankcase" thing. I was
> getting a little long in my note and left that off,
> but it is important.
>
> I don't have a "stack" of melted pistons, just 6
> or 7 of them. Most of
> them from the Kawasaki, one from the 494. Guess I
> am a slow learner. You
> would think that after a couple, I would get the
> idea, to lean, to bad !
> All caused by lean conditions, for some reason or
> another.
>
> Richard
>
> ----- Original Message -----
> From: "Chris Reinhardt"
> To:
> Sent: Sunday, August 27, 2006 4:56 PM
> Subject: Re: [F500] Melted 494 piston question
>
>
> > Richard I would clarify that a little bit. The
> top of the piston and plug
> deposists are dead givaways for DETONATION!!!!
> Usually timming, but could
> be a lean deto. A temp related sieze you would see
> the tell tale "4 Corner"
> stick meaning the piston expanded evenly all the way
> around. Lack of lube,
> will generally give a score on both skirts, along
> with blue'd wrist pin
> bearing. A lean sieze is usually a melt on the top
> of the piston closest to
> the exhuast port.
> > Warning!!!! A bunch of that aluminum that used
> to be a piston, is now
> in the crankcase. I would not even think of just
> cleaning up the jug and
> stuffing a piston in it unless I had a race that
> day, otherwise flush the
> crankcase best you can.
> >
> > CR
> > PS I have a stack of 125 pistons with every type
> sieze you could
> imagine!!!
> >
> > Richard Schmidt wrote:
> > Ken,
> >
> > I doubt that your piston melt down has to do with
> high water temp.
> Aluminum
> > deposits on the spark plug is a sign of a melted
> piston. Most likely
> caused
> > by too lean a fuel mixture to that cylinder. Lack
> of proper lubrication
> > could also cause a piston to seize, but this would
> not cause the top of
> the
> > piston to melt.
> >
> > A lean running engine will run hotter and put more
> energy into the
> coolant,
> > but this an effect, not the cause.
> >
> > Do not attempt to rotate your engine any more than
> you have. This could
> > cause more damage. The fix is to disassemble the
> top end of the engine and
> > remove the affected cylinder and piston. Carefully
> inspect the other
> > cylinder walls and piston for damage. It may not
> be necessary to remove
> the
> > other cylinder if no damage can be seen to the
> piston and cylinder walls.
> >
> > You can easily remove the aluminum welded to the
> cylinder wall using
> common
> > hydrochloric acid used for pool maintenance. Be
> sure to do this outdoors
> > and wear a good pair of rubber gloves. Make sure
> you are up-wind from the
> > cylinder and just pore a little at a time in the
> cylinder. You will get a
> > lot of bubbling action. Carefully rinse the
> cylinder with water and
> examine
> > it. Use a steel bristle brush to remove any
> oxidation. If some aluminum
> > still remains, repeat. The acid will not harm the
> steel liner. Be careful
> > not to get the acid on the other aluminum parts of
> the cylinder.
> >
> > When all the aluminum is gone, inspect the
> cylinder for scoring. If you
> > broke a ring, you may have scoring. Depending on
> how bad it is, you may
> just
> > be able to use a hone on the cylinder to remove
> some of the scoring and
> get
> > a cross hatch pattern again.
> >
> > Get a new piston and rings and reassemble. Piece
> of cake !
> >
> > As for the fastest way to get going again, replace
> the engine, most likely
> > no more that two hours of work. Of course you have
> to have a standby
> engine.
> > If possible, never go to the track without a
> backup engine. It may seem
> > like an extra expense, but if you add up all the
> expenses of just getting
> to
> > the track and entry fees, you will soon realize
> that you will actually
> save
> > money if you have a back up engine to run on
> Sunday rather than go home.
> >
> > Richard
> >
> >
> >
> > ----- Original Message -----
> > From: "Kenneth Kirkland"
> > To:
> > Sent: Saturday, August 26, 2006 10:32 PM
> > Subject: [F500] Melted 494 piston question
> >
> >
> > > Hello all!!!
> > >
> > > I'm an F5 newbie running my first season of
> regionals
> > > in the Midwest Division. I've been lurking on
> the list
> > > for a while but haven't had a question to pose
> yet. My
> > > first is a doozy.
> > >
> > > Apparently, a piston in my 494 melted down due
> to high
> > > water temps during a regional at Hallett on
> 8/6/06.
> > > There are some wonderfully shiny metallic
> deposits on
> > > the spark plug in the left cylinder. The crank
> will
> > > only turn about 45 degrees, with some metal on
> metal
> > > sounds accompanying what little rotation there
> is.
> > >
> > > I had hoped to run one more regional before the
> end of
> > > the year to get a national license when I renew
> my
> > > license in early '07. What's the best approach
> to
> > > remedy this situation? Redo the top end? Bolt in
> an
> > > entire rebuilt engine? What symptoms would
> dictate the
> > > need to work on the bottom end?
> > >
> > >
> > > Thanks for any and all assistance,
> > > Kenneth Kirkland
> > > MiDiv #18
> > > www.kirklandracing.com
> ________________________________
> FormulaCar Magazine - A Proud Supporter of Formula
> 500
> The Official Publication of Junior Formula Car
> Racing
> Subscribe Today! www.formulacarmag.com or
> 519-624-2003
> _________________________________
---------------------------------
Get your email and more, right on the new Yahoo.com
