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brought to you by:
Austin C. Davis
Author of:
"What
Your Mechanic Doesn't Want You to Know"
Reader Question: "Hello,
My name is Melissa, and I have had some problems with my vehicle and I
am trying to find an answer, or explanation about one question. I own
a 1988 Ford Bronco 2, and I took it to my mechanic because it had very
low oil pressure. He said that the crankshaft, lifters, oil pump, and
timing chain all needed replaced. Well, he did the repairs, and I picked
up my vehicle 3 days later. Very shortly after, the water pump started
leaking. The engine (2.9) had gotten hot a few times and now my mechanic
says that I have ruined a piston. Is this possible? Or did my mechanic
possibly do something that could have caused this to happen?"
Thanks Melissa,
Hmmm, Houston we have a problem! I can see how frustrated
you must be, and you're probably out some pretty heavy cash so far. First,
I would really like to know about the oil pressure. Was it really a problem,
or did the dash gauge just say it was? Just because the dash gauge (or
light) is reading low oil pressure doesn't necessarily mean that there
is internal engine wear. It could be a sending unit (which tells the gauge
how much pressure there is) or a faulty gauge. Anyway, a gauge problem
is relatively small compared to a piston problem. It would be nice if
you can verify you had a real oil pressure problem in the first place.
Yes, all these bad things can happen to a Ford Bronco ii...and unfortunately
it looks like it happened to yours.
Next, ask yourself these questions: Did the truck over heat after the
repair was made and was not over heating before? Did you continue to drive
the truck while it was over heating? The answers to these questions will
help you determine who should take responsibility for this problem. If
the truck really over heated and you continued to drive it…that could
be negligence on your part.
Your mechanic had to remove the water pump to do the crankshaft and timing
chain job. He could have disturbed the gaskets and caused the pump to
start leaking. This outcome is fairly common when working with older cars,
and performing large jobs requiring removal of parts for access. At my
shop if the pump looks like it is more than 2 years old, we would have
sold you a new pump when we did the crankshaft job. There should be no
extra labor charges since we already have to take it off, and replacing
it along with the other repairs can save you lots of money later on….like
now.
What is wrong with the truck now? Will it run? Does the engine miss or
run badly? A "bad" piston will cause the car to idle rough and
run poorly. Do you have white steam coming from the tail pipe? If the
piston is bad, it can cause excess pressure to build up in the engine
when it is running. This pressure can cause lots of steam out of the tailpipe
if there is sufficient water in the radiator to make steam. Here's an
easy diagnostic exercise that you can try while the engine is COLD:
- Remove the radiator cap and verify that there is
plenty of water in the radiator.
- Add water if necessary.
- Start the truck.
- Stand back and watch the radiator opening for a
few seconds.
If there is internal engine damage, you could see the anti-freeze shooting
out of the radiator neck. Do this only when the water and the engine are
cold or you will burn yourself.
If there truly is internal damage to the motor, you really should replace
the motor if you intend to keep the truck another few years. Realizing
that the mechanic already over-hauled half of the motor and you still
have problems, it still might be more cost-effective in the long run to
replace your motor with a rebuilt one rather than repair this damaged
motor further. Yes, you are looking at a lot more money, but in my opinion
that is the only way to fix this problem correctly if it really is a "bad
piston." The engine in a Ford Bronco ii is small in size to begin
with, and 14 years old, why beat a dead horse? Get another one (engine).
Now, if you are in the mood to take a gamble...here is another idea. If
you do have smoke out the tail pipe, and you do have an engine miss, then
you could ask your mechanic to remove the cylinder heads and have them
sent out to a machine shop to check for cracks. At that time the mechanic
can look at the pistons and see if there is a problem. If he does not
see a visible problem with the pistons (and to be honest they are "probably
ok") then tell him to have the cylinder heads re-surfaced and replace
all valves, valve guides, and valve stem seals.
The mechanic will have to replace the head gasket when he does this job,
and that is probably the problem anyway--a "blown head gasket."
This fix will "overhaul" the top half of the engine. It will
get you by and would be cheaper for you at this time, but it won't be
the best fix for an older and probably high mileage vehicle. Remember,
the pistons and all the other internal parts got just as hot as the head
gasket from the over heating, and will probably need to be replaced at
some point…but this fix would give you the chance to start saving for
the new motor or a new truck.
If you choose this alternative, ask your mechanic to cover the cost of
the labor for at least half of this job. Why you ask? I suspect a leaky
water pump caused your truck to over heat, and this pump probably should
have been replaced at the time of the first repair. I also feel that the
mechanic should be willing to cover some of the labor cost associated
with the next course of action that needs to be made. The short amount
of time that has taken place and the large amount of work you just paid
for should also be in your favor. It will take him about 10-12 actual
working hours to complete all of the work, so you are not really asking
him to "give you money back", but rather perform the job at
a reduced rate for customer goodwill.
You will need to purchase (from the mechanic, so he at least makes a few
dollars from this job) the head gasket set for this job…maybe $75, thermostat
and misc. small parts $30, the radiator cleaning and the cylinder head
work at the machine shop…$85 and $225 respectively. And of course a new
water pump, not rebuilt(I have never had good luck with them)--$70. Once
the work is completed, you will have had a valve job performed on this
motor. You will be out a few hundred dollars, but at this point it might
be a good option for you if you can't afford to replace the motor at this
time. Your mechanic can remove the egg off his face due to not inspecting
the job thoroughly, and you might continue to do business with him? It's
the best win/win situation for your current predicament.
Some other things the mechanic should do when performing the head gasket
job: replace the thermostat and check inside the radiator for any corrosion
buildup or blockage. Normally when we do a head gasket job we send the
radiator to a radiator shop for internal cleaning. The cause of the head
gasket failure was due to over heating, so anything that could improve
cooling of the engine should be checked and or replaced at this time.
I
talk about other problems like this in my eBook
"What Your Mechanic Doesn't Want You to Know"
Which just happens to be on sale
right now
Along with two free money saving reports with your order
Click
here now
I hope this helps. 
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