Bill Freeman wrote:

  4)  The **best** solution is still to use EXTREMELY high quality
       plumbing on your system.  I do believe that hose clamped
       systems CAN be made reliable (witness all the Hondas and
       Toyotas out there)  IF, IF,  IF they are VERY carefully
       engineered with highest quality hoses replaced regularly and
       *proper* fittings and clamps.   Spring type clamps are the

standard

       on Hondas, and I believe are more reliable than screw type, which
       can lose tension  as the rubber crushes beneath them with heat and
       time.   My screw clamps on the air induction tubes (rubber hose
      connectors) of my Lyc are essentially always in need of a bit of
      tightening.

  Feel free to tear this apart and improve it.

Bill Freeman

Bill,

  McMaster-Carr sells worm drive hose clamps that incorporate a belleville
washer scheme to address the issue of loosing torque due to repeated
heating/cooling cycles. Refer to their website at:

http://www.mcmaster.com/

  Under the heading "Pipe Fittings and Pipe....." select hose clamps. When
that window pops up go to page 3 and see constant torque hose clamps. The
clamps are a bit pricey but sure look to be a good solution to the problem.
I'd appreciate your review/comments.

  I know that the use of hose and hose clamps is a real problem for some
out there. Having just replaced the factory original radiator hoses on my
84 Nissan pickup (not because they were leaking but because I was replacing
the radiator and thought I might as well do the hoses too) I fail to see
the issue. I think the automotive industry has proven them to be a reliable
choice when properly done.

Mike Wills

Mike,

  My Hondas (86 to 01) all have spring hose clamps.  The 01 Accord
has pretty thick metal, I estimate .040" thick steel.  These will accomodate
a lot of growth/shrink cycles and keep a pretty consistent tension on the
hose.  With a proper diameter match between hose and fitting, and a good
spring clamp, I think this can work.  I replaced ALL my hoses on my 89
Accord at 200K miles and cut a bunch of them open.  All looked just
fine except one kinda thin walled intake manifold heat hose that was
buried under the engine.  It was squishy and a bit bulged.  The main rad
hoses looked nearly new and cut and flexed like new.  I would want
long runs to be mandrel bend aluminum tube with professionally rolled
beads, properly sized for the short connector hoses (~6") at the ends.

Perry used AN hose barb fittings and apparently got some leakage, altho
I wonder how much was due to spiking pressures as the flame pushed out
into the coolant.  I think most of his plumbing looked pretty good in the pix,
but I would try the spring clamps rather than worm type.  For what its worth.

Bill

 
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