THANKS EVERYONE...for helping me solve the overheating problem on my 96 Ford
The user "Backyard Mechanic" posted a link to somebody elses web site that
had pics of their problem and it really sent me off in the right direction.
I won't do a whole web site, but I did do a simple little page that I'll
leave it up for a week or so if anyone wants to see how badly the impellers
were damaged inside the water pump. You can see it at:
Good pics.. but arent they reversed?
The coolant/antifreeze had become so corrosive at some point (even with
coolant flushes and refills)
Got any idea what's in a 'coolant flush'?
besides Money for the people that do it?
I have never done a coolant flush to any of my cars and I am not the best
at preventive maintenance... And I've never had a corrosion problem
But then, I've never had a car that had that yellow antifreeze in it
BTW... what good do you think an "Engine Flush" would do?... You know the
ones that oil-change places are advertising..
Think about it. It 'clears out' oil passage deposits 'real fast'. Where
do those deposits go?
Unhhh two more things:
First, I wasnt criticizing YOU, Phil, in any way.
Second, I'm wondering about the particular symptom here.. that is of the
impeller 'sacrificing' itself.
Here's an 'official view' from:
That means that as the coolant passes through the pump, bubbles are
produced, which then collapse with explosive force, pockmarking the
internal parts of the pump. That pockmarking is erosion, the marks being
exposed, unprotected metal. If the inhibitors work quickly, the damage
stops after minor corrosion. If they work slowly (as with organic acid
inhibitors), the pockmarked areas corrode for a longer period.
Does any know if the pump seal composite was changed for this series?
The old ones had a carbon/brass seal, if I recall. Changing one of those
two surfaces would result in either galvanic (maybe) or electrostatic
(probable, from the looks of it) eddy currents through the shaft.
Bet that was the problem rather than the coolant itself.
Found another site, which pretty much says whatever we use... we're
pretty much DOOMED!
Note the bottom article; reading between the lines, it tells us that
using an aluminum protection coolant in an all-iron engine like the
Vulcan causes problems.
Not only that...using distilled water also can cause damage, due to ph
Screw it.. gonna just keep on doing what I'm doing.
First, I never felt that you ever criticized me...I apologize if my response
gave you that impression.
Second, Ford's resolution to the problem as outlined in a TSB was to change
the coolant path by adding a "coolant bypass" system. Their $135 kit (plus
labor to install it) included a couple 3/4" tee connectors, a couple pieces
of 3/4" hose, some hose clamps, and a restrictor. In simplest of terms they
cut the two heater hoses (going into and out of the heater core), installed
the tees, and added another piece of hose between them. This apparently
gives an second path for the coolant to flow in addition to the path through
the heater core. How this was going to solve the problem of coolant turning
brown and engine overheating, I don't know.
The conspiracy theorist side of me thinks that this was done to cover up the
fact that they had some really bad water pumps (not made to specs or, more
than likely, the specs were wrong to begin with (wrong material). This is
what caused the impellers to erode/corrode, thus turning the coolant brown
and causing the overheating because there wasn't enough impeller left to
move the coolant.
Anywho...thanks again for all your input,
I would suggest you install the restrictor in the degas line, if
nothing else. You can make one out of a short length of bolt with a
1/8" hole drilled axially through it.
By the way, the redesigned impeller looks like this:
Not corrosion, Phil.
It's from a poor choice of impeller material for the shape & design of
the impeller design and the housing. The impeller was cavitating in the
coolant mixture, actually boiling off the impeller fins in low pressure
pockets and taking a tiny microscopic bit of material with it each time
a bubble boiled off. This could, and probably did happen at
temperatures much lower than the 212 degree sea-level boiling point.
If it was corrosion, the failure would have been around the hub equally
with the blades.
I'm sure there is a technological difference between corrosion and erosion,
but you obviously understood what I meant. Maybe it's a combination of both
in this instance...the corrosion being the chemical reaction that caused the
impeller material to weaken/disintegrate and the cavitation/turbulence that
happens more extensively at the edge of the fins of the impeller causing it
to erode more quickly there. There was evidence of erosion/corrosion on
what remained of the impeller as it was significantly thinner than a new
I'm not an engineer, although I play one on TV. ;-)
I once drove an 85 Ford 3.8 70 miles with a dry radiator (not on
It ran very hot but not pegged to the max. I suspect the mobil one oil
helped out here quite a bit as well as perhaps a loose engine after
200,000 miles of use. Drove the car another few years after that
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