[xj40] Air Pump Failure, not

Well finally got the air pump off, it spun with finger tips and the
clutch actuated.
The relay was corroded so I cleaned the pins and coated with
dielectric grease but couldn’t figure how a freely turning air pump
could cause the 3/8" adjusting bolt to be snapped in half and the air
pump mounting bracket to be ripped off the block when the belts were shredded.

Scratched head, spun the alternator OK
Scratched head again, spun the AC OK
Scratched head again, spun the fan blade before realizing it was on a
viscous coupling.
Turned the water pump by hand (not). Water pump was frozen.

Apparently the water pump bearing had been failing for some time
which accounted for the failure of the volt meter in the instrument
panel to register charge immediately or in the normal slight delay
(it has to wait for the dump module to begin dumping excess
current). Apparently when I revved the engine the belt slipped
enough on the binding water pump enough to spin the alternator (which
accounted for the vibration I though was caused by the air pump
clutch as well as the batteries that kept going dead and long delay
before the voltmeter showed charge).

What misled me was the engine would over heat occasionally and it had
a small leak some where near the water pump according to the radiator
shop I had taken it to. So I assumed the overheating was due to the
leak. I have only driven the car back and forth on local errands and
never look enough to really overheat and apparently the pump was
moving some etc. So I never realized the water pump was failing and
the shop never checked or told me. Kind of lost faith in that shop
(I left the car with him for a week last spring and he couldn’t stop
the leak and apparently did not want to take the car apart. I wanted
him to take the radiator out and replace the oil seals while at it
but apparently he didn’t want to fool with it and told me it didn’t
need work. All he would do was point me at the front of the engine
and say there was a small leak.

Well some bars leak solved the problem of the small leak or most of
it anyhow. Being busy on other things I put the car in the garage
and decided to work on it later.
Also I had the battery going dead and never associated the dead
battery with the frozen water pump.

When I got the air pump off I noticed the hose on the water pump was
not fully on the spigot and was cocked to boot which was where the
leak was coming from or so I thought.

Moral of the story check the water pump. I still haven’t got the
broken bracket off the engine (the piece that’s left has 4 -10 mm
bolts holding it to the block in relatively awkward spots to get a
socket on and they wont budge).

So the water pump fooled me on the alternator issue, dump module and
dead battery problem and was the reason the air pump was ripped off
the engine, Shame on me. Sometimes no matter how you analyze things
on these cars they find a way to fool you.

My bet is that a new water pump will solve my slow water loss,
battery failure and alternator dump module concerns. The good news
is I don’t have to pay $303 for a rebuilt air pump, the bad news is
I’m sure the water pump cost as much and it looks like I might as
well remove the shroud and replace the rubber flaps while at it and
see if I can find the oil leak. I’ll probably remove all the
radiators to be sure they are clean if nothing else, get my hose on
right and find the oil leak. Looks like I’ll be spending a bit of
time on it too since all the bolts have been there 18 years.

Jay 90 VDP Majestic

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