You speak of VERY little experience. Yes you work on your precious old car, I
work in the field and have most likely more years than you are alive. The fact
is if you are out of coolant you just lost heat transfer. The combustion
chambers over heat while the rest of the block slowly absorbe the heat by
contact. Until the heat transfers to the rest of the engine the coolant gauge
will most certainly read normal if not cold. The red light will act the same
way. If the cooling system is low the light or gauge will read normal to hot
back to normal as the air pockets come and go. It is a fact. Many customers
continue to drive after they see lots of vapors escape from under the hood and
notice the coolant gauge drops. They think it's ok till the car just stops. The
engine is now destroyed.
Nice theory, but the steam in the system from whatever amount of coolant is
remaining in the block is enough to heat the sensor enough to read hot. I've
seen this on small block Fords and also heard the same from others. That is
to say people who have observed a car with the radiator drained trip the
In my experience a small block Ford (an engine, not a "precious old car",
which has been in production well into the '90s). Furthermore, I'd hardly
call en engine which has been run until overheated destroyed. Common
failures in an engine subjected to such conditions are head gasket damage,
ring damage, and possibly bearing damage also on aluminum headed engines the
heads will sometimes warp. All of these are fairly cheap fixes and the
engine is by no means "destroyed". A simple hone, re-ring and new bearings
and possible milling of the heads is usually enough to get the engine
running well again.
You keep on believing whatever you like, but I sure as heck would never let
you touch any of my cars with a 10 foot pole. Your ineptitude is glaringly
With an good used engine running between $500 ~$2000 for most cars and
with shop rates running between $50 & $100 Per hour your "cheap fixes
can quickly eclipse the market value of the vehicle. Even if the
engine rebuild/ "cheaply fixed" is done any reputable mechanic will
have to install new belts hoses & fix whatever caused the overheat.
Add to that the cost of a rental vehicle what the engine is being
"cheaply fixed" and you're starting to talk money.
A simple "milling of the heads, hone, re-ring, new bearings, magna
flux, etc, etc, etc." costs money in the world that I live in.
Perhaps it's cheaper on the planet that you reside.
Personally if I am on a tight budget I will just do the minimal amount of
work it takes to get the motor running properly again. That may mean not
doing a full rebuild (which may not be necessary anyway), or even fully
disassembling everything, let alone magnafluxing the block and/or heads
(which really wouldn't be necessary unless overboring by a large amount).
Rings - $25
Main bearings - $23
Rod bearings - $23
Head gaskets - $28
Intake manifold gasket - $8
Oil pan gasket - $9
Incidentals/misc - $25
So for under $150 a cheap 'rebuild' can be done. I quoted those prices from
Advance and they are for a small block Ford. If you are on a tight budget
you may not even need to replace all or even any of the bearings in an
engine that has been overheated. Perhaps the rings survived, whihc is not
The rings were fine on the 289 which I ran without collant for 500 miles,
most of those miles were WOT on the highway doing 75-85 MPH. When I sold the
car 7 cylinders read 100 PSI on the dot, and the one that read low (~60 PSI)
was low due to a burnt exhaust valve. That valve was burnt when I put the
heads on the car. I needed a car right away so I put to gether what I had
and other than being low on power form the open chamber ehads it ran quite
In any case, $150 for a cheapie 'rebuild'. If the heads are warped/not flat
they can be resurfaced for $100 or less. $250 for a freshening up that
should last a good while is not bad in my opinion. I mean honestly, compared
to the potentially several thousand dollar shop work you propose it doesn't
seem bad at all. Heck, if you don't wanna spend the money to have the heads
resurfaced at a machine shop you can do it yourself with a belt sander
(works wonders on exhaust manifols, and will do just fine on heads). These
things can be done for cheap. The book value of my car is much more than
This stuff may seem a bit overwhelming, but honestly anyone with a little
patience and desire to learn can buy a book and rebuild an engine. Sure the
average Joe probably couldn't do all this in a weekend if it was his first
time, but the point is that an engine which has been overheated is far from
destroyed. Something that might destroy an engine is throwing a rod. When
that rod breaks loose it can take a lot of things out before it puts a hole
in the oil pan. With a destroyed crank, at least one head, possibly block,
possibly other parts of the rotating assembly (depending on how it broke,
what it hit on the way out, what RPM it let go at, and how quickly the motor
was shut off) that is when one may consider an engien destroyed, instead of
just broken or in need of repair. In any case, $250 sure beats $2000-$4000
for a new engine.
How so? Fact is if there is no liquid in the system, no steam. When a hose blows
the liquid is pumped out by the pump the rest is boiled off. No theory, basic
Once the area that the sender is screwed into gets hot enough yes. With out
coolant, there is a lag. Coolant which is liquid is the heat transfer medium. If
the red light comes on or the coolant temp gauge shows hot with out liquid in
the system, the engine is now damaged enough to be beyond cost effective to
repair, replacement is the cost effective route.
Run with out coolant is destroyed. How many have you taken apart after 10 miles
of no coolant at 70 MPH? Even an engine with low coolant will suffer enough
damage to be replaced not repaired. The cost of parts, machining and labor would
put the repair easily over the cost of a re-man engine.
Cracked heads. broken pistons and rings that damage bores, stuck valves that
impact the pistons causing piston damage and head damage. That only names a few
very high overheat damage.
Only to be back in the shop a short time later, you just gave the customer a
free engine. Do that enough times you are out of business. Now you also have the
problem of a bad rep which has the highest price value because you have no idea
how many customers you lost because on that one upset customer.
Keep reading "popular hot rodding" and other rag's of the like. You will remain
as ignorant as you are well into the future. Others in the past has told you in
posts that you are very ignorant, I'm doing the same.
So now you're changing the situation. Originally we were talking about my
'67 289 which I ran for 500 miles at WOT on the highway with only the small
amount of coolant left in the block after draining the radiator and pulling
the heads. No leaks in thes ystem, just a very small amount of coolant.
I've never argued that point. I thought that was obvious that with only
steam in the system vs a liquid there would be a delay to the temp sensor.
Not necessarily. $250 for a budget 'rebuild' (rings, bearings, resurface
heads) could very well do the trick (which is certainly cheaper than
$2000-$4000 for a enw engine). In the case of my 289 the rings and bearings
were just fine. I had 100 PSI on the dot across 7 cylinders, the one that
read 60 PSI was low due to a burnt exhaust valve which was a problem when I
put those heads on the motor. The bottom end at that time had over 200,000
miles on it and the original heads only failed when revving the motor to 7
grand one time too many for heads with 200,000 miles and worn valve tips,
resulting in a snapped rocker stud.
My 289 (200,000 miles on that engine) was run with virtually no coolant for
500 miles at WOT, doing 75-85 MPH. That's 6 hours of run time. I never tore
into the bottom end, but as I stated it did make 100 PSI on the dot on 7
cylinders and the only reason #5 read 60 PSI is because of a burnt exhaust
valve which was present when I swapped the heads. Those 500 miles with
hardly any coolant were right after swapping the heads.
Possible, but unlikely. Most engines I've seen that have overheated run just
fine. Obviously my 289 was an exception to the rule. I believe most motors
would have seized up under such conditions.
I'm not running a shop. I'm talking about an individual fixing his own car.
If I were running a shop I would recommend a complete disassembly and
rebuild if going so far as to do a re-ring and replace the bearings. When
paying someone else to do the work the additional cost of machine work and
such is relatively small when compared to what one is paying for the 'budget
I don't read such magazines. I speak from experience. Also, I could take
plenty of potshots at you based on what opinions others have expressed about
you, but I won't. There's not much point in that. I'm debating/arguing an
issue here, not bashing you.
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