I5 Block heater - long followup report

QSHIPQ at aol.com QSHIPQ at aol.com
Fri Jan 24 09:01:09 EST 2003

Ok boys here's the poop...  First thanks to all with btdt.  Here's where we
are as of the new mellinium.

The problem with the block type heaters (103 and 106PN) is that the turbo
cars can't use them, as they are to be mounted where the water feed is on the
WC turbos, and it's darn close to the turbo for non WC applications.  The
dealer no longer stocks the ZAP PN (at least that's what my Chicagoland
dealership networks say)

I also spent over an hour in my local NAPA, with literally hundreds of in
stock block heaters (the 2000watt one would make tim allen proud, for a
18wheeler).  I pulled a bunch of instruction manuals to get a feel for what
direction we should be heading.  Basically, for automotive applications, the
consensus is that for overnight plug in, no more than 850watts should be used
(600max recommended for 10liter A/F capacity motors).  Above that, it's meant
to be used for a couple hours of preheating.

There are 5 types of heaters available in order of desire:   dipstick mount,
freeze plug/oil immersion, magnetic mount, water circulation type.  They are
rated on wattage and constant temp.  Wattage varies from ~60 for the dipstick
to 2500 for the water circ type for the big rigs.  Temp for automotive is
usually between 350-300degrees F.

Scores:  Forget the dipstick, it's a joke.  Freeze plug is good, and
relatively easy to install and forgetabout.  Oil immersion is a long probe
into the oil pan, but MUST be fully immersed when in operation or it burns
itself out pretty quickly.  Best used for big rigs where oil capacity is in
the gallans, not the quart.  Magnetic mounts are pretty slick, and are the
'new' hype for the millinium (more below).  Water circ type are actually
pretty cool, but one manufacturer specifically warned against using on import
cars, especially water cooled vw's.  My bet is that this has to do with the
heater valve shutoff preventing proper circulation, since these are supposed
to be mounted in the heater circuit at the back of the water pump.  So, I'll
concentrate this report on the magnetic mount type.

KAT and Zerostart are the two manufactures of magnetic mount type heaters -
Balkamp, echlin and puruit brand names appear identical, guessing private
label.  They come in a variety of sizes, the two most common are 200w and
300w.  The 200w is meant for small engines:  Snow mobiles, chain saws etc.
The 300w type is meant for automotive.  Retail on the 200w is about 40bux,
retail on the 300w is about 60bux.  The size of the 200w one is about 40
credit cards thick.  The 300w one is about double the area.   The newer style
ones have plastic install/removal handles (don't do a bob dupree, he stamped
the model number into his hand last year:).  The magnets are damn strong, and
I doubt you could shake one loose on a prorally.  The 200w unit comes with 2
rows of magnets the 300w one comes with 4 rows of magnets.  Both are rated in
the 275 degree category.

Both also come either UL listed or UL not listed, I couldn't tell the
difference in the actual unit, other than the cord is UL stamped one the more
expensive "listed".  The 200w unit comes with either a 6in cord or a 6foot
cord (the only difference between two model numbers).

FYI, I ordered 1 300w unit and 1 200w unit, figuring I should be well covered
for steamboat.  A single 300w unit is probably acceptable for 90+ percent of

NAPA carries the zerostart brand under their echlin banner, and is a stock
warehouse item, but they only show the 200w unit available.  The KAT brand
(Fivestar Manufacturing) has both a 200w unit (same as the ZS in size and
design), as well as the 300w unit.  Most autopart stores can get it same day.
The 300w unit is K1160.  My apologies in advance for v8 quattro guys, not
sure where you'd mount it.


Scott Justusson
All hot and not bothered for steamboat

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