Date: Thu, 21 Oct 1999 20:15:54 -0700
Reply-To: "Tom L. Neal" <jneal@NETCOM.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: "Tom L. Neal" <jneal@NETCOM.COM>
Subject: 1st Most important specialized waterleaker measurement device
Content-Type: TEXT/PLAIN; charset=US-ASCII
...continued from "2nd most important specialized waterleaker measurement
device" (Digitool). A couple of days ago Darrell posted his belief, and
here's my reasoning to support it.
1st place most important specialized measurement device for a waterleaker:
The name says it all. These "suckers" don't suck, they leak. My van has
had at least 25 leaks and many of those leaks happened at very
inconvenient times, of course. This unreliability is not particularly
surprising for a cooling system with well over a hundred parts, and
may be the most complicated one ever put into a passenger vehicle.
On the days that some list member isn't describing a fuel injection
problem that the digitool would probably identify quickly, someone else is
describing a coolant heating, light blinking, dribble leak, blown
pipe/cap/connection/headgasket/etc type problem. These are sometimes
difficult to troubleshoot, since they tend to happen on the road more than
sitting still at idle. Many of these problems can leave an unprepared
person stranded, and can cause a lot of hassle even for a prepared person.
The cooling system is the most unreliable subsystem in a waterleaker, even
worse than the notorious fuel injection system.
So, what is the best way to identify leaks? Darrell insightfully suggested,
"a water pressure gauge", and after thinking about it a while I agreed,
with one addition: a coolant system pressure checker. With the
combination of these two tools, the owner has much more ability to
identify early, and diagnose correctly, many coolant system problems.
A coolant system pressure checker is very effective for precise driveway
testing of coolant system integrity for a wide variety of problems: slow
leaks, fast leaks, water pump, defective caps, expansion tank cracks,
leaky connections, heater cores, and others. It has already identified
six leaks or incipient leaks on my van after using it only a few times. I
even carry it on trips. At $100+ it costs more than the average tool, but
I would have saved that amount many, many times due to the pricey
inconvenient problems my coolant system has had.
However, the static testing of the coolant system pressure checker doesn't
monitor real operation. That's the job of Darrell's coolant pressure
meter. It will point out big and little water leaks as they occur,
compression leaks into the system (haven't proven this, but it makes sense
that the pressure should go up erratically since the tank cap may not
respond quickly enough), defective caps, and most importantly when the
little blinking light comes on it will help the quick diagnosis of the
type of problem indicated, directly. Idiot lights tell you to either
"stop now" or "slow gradually down and find a convenient repair place to
fix a problem" and it's hard to have enough information to know which
choice is being indicated. The pressure meter helps.
Darrell has provided us with valuable insight and I finally agreed with
him. The combination of these two tools is the most important specialized
measurement capability for maintaining a water leaker since they allow
quick identification of problems in the coolant system, the waterleaker's
most unreliable subsystem.
Does anyone have a coolant pressure gauge mounted? Darrell suggests the
Overton unit, which I haven't started looking for yet. The latest
Princess catalog has some 0-30# gauges on close out, 1 1/2 inch for $3,
and 2 1/2 inch for $6 and I've ordered some to try them out.
Any ideas for the best way to hook into the coolant system? I'm
thinking of hooking into the front heater lines with a T and an on/off
valve which leads to the meter mounted under the radio.
Any other thoughts on valuable measurement techniques? I really like
JP's digital panel meters.
Cheers, Tom Neal '87 syncro waterleaker, at least 25 times
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