On Sat, 10 May 2008 05:00:37 -0500, email@example.com
Vapor lock is not likely your problem since it has EFI that
operates at pressures much higher than a carb system and
constantly recirculates cool fuel from the tank thru the
If it is turning over slowly, that would likely be a starter
problem. Check all connections to be sure they are tight
and clean. IIRC, that model has two starter solenoids; one
on the right inner fender and the other on the starter. The
most likely candidate is the one on the fender which is easy
to get at and replace. It is also cheap. The other
solenoid on the starter has an ignition wire that frequently
corrodes or becomes loose. It is a spade connector that is
easy to get at from under the right side. Make sure that
connection is clean and tight. Put some electrical grease
or jell or whatever on the connection to prevent future
Don't forget the starter may be due for replacement. If it
turns the engine easily when cold, it should be OK but, that
is no guarantee. Many auto service centers or parts stores
offer a free evaluation of the starting and charging system
to be sure the charging system is up to par, the battery is
strong and the starter is not drawing too much current.
Your problem should be an easy fix.
On Sat, 10 May 2008 10:19:11 -0700, "Ted Mittelstaedt"
Is the starter prone to turning slow when it gets hot? Why?
Every electric motor I have ever known work at most any temperature,
not considering the load on them, like air compressors often trip the
breaker in very cold weather, but that's because the compressor oil is
thick. My engine oil should be thinner whne the engine is hot, and
thats when it wont start. The other day I pulled home a heavy load of
hay and the engine was working hard. I parked the truck went into the
barn to disconnect the electric fence, got back in the truck (one
minute after shutting it off), and it would not crank over. Acted
just like a dead battery, yet all indications showed the battery was
ok (volt meter, radio, horn, lights all worked). I decided to go eat
before screwing with it. An hour later the truck started just fine.
I always starts immediately when cold, even when the temp was 20 below
zero in winter. The minute it gets hot, it wont crank over. That's
why I thought the cylinders were flooding with gas vapor.
This is the first fuel injected vehicle I have owned, I know carbs
used to vapor lock and flood cylinders, I dont know much about fuel
inj. I'll suspect the starter, but it dont make too much sense that
the temp would affect an electric motor of any type....
this is a classic case of a bad starter.
once the starter gets hot, it requires more power to turn than the battery
then when the engine and starter cool off, it starts fine again.
another thing to change while the starter is being replaced, is the battery
cable from the solenoid to the starter.
for the few bucks it costs, it is money well spent
One question though. What part of the starter is affected by heat to
need more power? Do the starter bearings get tight? Do the stator
coils somehow expand, does the rotor enlarge, do the brushes lose
contact, or what? I just can't picture how heat would affect any of
that. I know when any of these parts of a starter go bad, the starter
dies, but how can heat make it temporarily go bad? However, I am
aware that metal expands when heated....... ????????
Electric motors work fine up to around 300 F or so. Much beyond that
and you start having problems with the lubrication in the bearings not
working, unless the bearings were designed for high temperatures and
are internally lubed with high temp lube or some such.
Exhaust manifolds close to the engine run at around 1200 F. (think, what
is the temp of fire?) They put out a lot of infrared energy. If your
is right next to one, and it is close to the exit point of the exhaust
in the engine, the radiant heat from the manifold is enough to heat the
a lot past 300 F, to the point that the bearings lose lube. Once that
too many times the bearing races start to fail. When things cool down the
starter turns a bit easier.
Usually you see these problems when people put headers on a vehicle
since the header pipes run a lot hotter further away from the engine, if
they don't wrap the headers or put in a heat shield. But some vehicles
also have the starter located close enough to where they need a heat
shield and the factory puts one on.
It's not uncommon for amateurs changing out a starter to forget to put
the heat shield back on, and since everything works fine for a while they
figure the shield wasn't doing anything useful.
Correct me if I'm wrong, but the "vapor" in "vapor lock" was in the fuel
line from the tank to the engine. IIRC, it happened mostly on engines with a
mechanical engine-mounted fuel the pulled the gas from the tank to supply
the carb. The gas in the line would heat up and vaporize, causing the pump
to try to pump the vapor (which they didn't do very well at all). I had a
'64 Galaxy with a built 390 that was prone to it when I lived in southern
We get vapor lock issues today, half my jobs fleet went down a few years ago
when it got into the '80's on a March day in the northeast. Still were
burning winter blend fuel and half the fleet of Econolines wouldn't hot
restart or died on the road.
Loosening the gas cap to let the pressure out and 15 min. cool down got them
restarted and leaving the cap loose kept them going till the day cooled
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