Jim,
I took Daniel's advice about heat treating the intake and the header because I
had the same symptoms. On a hot day when I got stopped at a traffic light, the
revs would go down, and when the light turned green I would stumble and sputter
away for several seconds before it returned to normal. I did not have a heat
shield either.
http://www3.sympatico.ca/robertduquette/temp/Intake009.jpg
I still don't have a heat shield and the jury is still out as to whether or not
this has cured my ills, as I haven't had hot weather since. ( It's coming
soon! ) I found, accidentally, just before removing the old header, that it
was cracked and there was a fair breeze coming from it under the carbs. So
far, so good!
Daniel, couldn't "Overheating in traffic but Not overheating on highway
running" also be indicative of a heat build up in the engine compartment due to
lack of airflow? I guess an electric fan would help this too? My temps "seem"
to be lower with the coated header, but 190 isn't too high, is it? My thought
was that it was a fuel vaporization problem causing the stumbling and as soon
as I got cooler fuel coming through, it would run right again.
My '65 Sprite used to not want to re-start after running for awhile, shutting
down ( running into a store and back out ) and attempting to re-start. I
believe this was vapour lock. Wasn't there some story going around about
someone with a Sprite that didn't like vanilla ice cream? :) My Sprite had a
heat shield. But, when ( if I ever get a round toit ) I reassemble it, I'll
heat coat the manifold ( or header, if I get one ).
And, speaking of my Sprite, I must say that I was extremely disappointed to
return home after my recent absence to find that you guys didn't break into my
garage and restore my Sprite tub. < just kidding > Actually, it's a good
thing that you didn't, as my father-in-law was taking care of the house and
he's ex-military, if you know what I mean. At some point, I'm going to get
back on track and do this myself, so brace yourselves for 1,000,001 questions
and a brazillion ( yeah, I know ) pictures to accompany the questions.
Robert D.
> -----Original Message-----
> On Behalf Of Daniel1312@aol.com
>
> Jim,
>
> A thermal barrier coating on the exhaust manifold or inlet manifold or both
> will achieve a lot more than any carb heat shield will and while not that
> cheap
> will be money you won't regret spending for many years if not decades.
>
> Overheating in traffic but Not overheating on highway running suggests the
> engine driven fan isn't delivering enough cold air to cool the radiator.
> There
> is a ton of stuff you can do to drop coolant temperatures but for you
> problem
> I'd be inclined to consider an electric fan first.
>
>
> Daniel1312
>
>
>
> In a message dated 29/05/06 01:41:20 GMT Daylight Time, bmwwxman@gmail.com
> writes:
>
> > 3) What is normal water temperature on a 1275? Mine reads about 170
> > degrees once the thermostat has opened and I am cruising along at
> > speed. Once I stop and let idle in 90 degree or warmer air temperature
> > (or in slow moving traffic), it begins to heat up, eventually making
> > it up over 190 degrees at which point the engine starts to get baulky.
> > I have a new radiator and thermostat and am running just water with
> > some water wetter in it.
> >
> > 4) What causes the baulkiness and eventual stalling above? I have an
> > HIF44 on the 1275 which runs beautifully except when the engine heats
> > up. Could this be the lack of a heat sheild between the carb bottom
> > and the exhaust manifold??
> >
> > 5) If the heat problem above IS due to the lack of a heat sheild,
> > where can I find one for my HIF44 carb?
> >
> >
> > Many thanks in advance for the help!!
> >
> > Cheers!!
> > Jim - 68 Midget in Dodge City
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