From time to time I run into a water tube stuck in
gear case situation...most recently with a "mixed parts WD4S. It is possible (after removing fasteners)
to pry the gearcase away from exhaust housing and
slip a hacksaw blade in to cut the tube...this leave
a hard to grasp stub stuck in gear case and a useless
piece of tube in exhaust housing to deal with.
The other method is to reduce the flare in tube and
remove tube and gear case together....which is the
method I used this time.
Took the gear case and tube to garage for a heat and
beat using MAAP torch and a solid piece of wood...
took a lot of heat and beat but eventually tube came
free of gear case...HOT!
Laid the old tube on a piece of 2x6 and nailed a couple of sticks on either side of the long straight
section forming a slot...traced the curves and bends
onto 2x6...cut a piece of 3/8" copper tube a little
long, placed in slot and bent to the traced curves
and bends...as nearly as possible.
Took a bit of cut and try to fit replacement water tube into exhaust housing...required trimming and
adjusting bends/curves to get tube to poke thru the
hole at top of housing...then used file to flatten
and a phillips screwdriver to form a flare. Tube
that stuck out bottom of housing trimmed to extend
2 1/2" and job done.
Used copper tube may be work hardened...heat to redness to make tube full soft which makes bending easier.
Remember you can cut too long shorter, but, you
can't cut too short longer. Cut tube a little long
on both ends.
Louis, I use the un-flare, re-flare method also. When trying to thread the tube with foot back into the tower I find that sticking a rod down in the tube, so that it is longer, helps to guide the thing into place. The rod comes thru the hole first, allowing you to grasp it and guide the tube thru the hole.
Cheers, JW in Dixie