Miq sez:
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Now about this rope stuff, could someone explain what the theory/trick is
supposed to do? I have rebuilt quite a few engines in my time (though there
doesn't seem to be as much of it lately) and ma at a loss as to what this rope
stuff is supposed to do. Is it really rope? You mean go to the hrdware store
and pick up a bunch of hemp? Is is something else? What do you do once you
have stuffed "two fathoms" into each cylinder?
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I mentioned this in a previous post as a hoary old trick; I think I
first read a reference about it in a Ford Model A manual!
Yes, it is really rope, but to do this right, you need NON-COMPRESSIBLE
rope like Staset-X Yacht Braid or any other modern Dacron/Kevlar material;
Nylon, Polypropeline, or hemp will compress, and you run into the
situation where you have to back off and keep feeding more rope in through
the spark plug holes.
The theory behind all this is that the rope acts as a means of distributing
the pressure over a relatively large surface area: the combustion chamber.
(I neglected to add that the rope is fed in through the spark plug holes
at BDC before the compression stroke, otherwise valve damage can occur.)
The rope surface is soft enough to prevent damaging any parts, and if the
technique doesn't work, you can always fish it back out again. (Remember
to leave the tail end sticking out of the spark plug hole! It is most
inadvisable to stuff all that rope in and then screw the spark plug down!)
This is a much better technique than trying to pry the head off with a large
screwdriver or trying to run the engine with the head bolts loosened: the
first technique is crude and damaging; the second technique is dangerous
and usually impractical if the manifolds and H2O pump bolt both to the head
and the block.
Good rope (Note that it is called "line" in nautical applications, only
stinkpotters call it rope on a boat:-) runs about $.60 a foot at Marine
discount stores; and like Sam Gamgee, I believe only fools travel any
distance without a hank of it handy.
Next installment: used spinnakers as portable garages.
Aran (That's Capt. Aran to you landlubbers!) Guy guy@bevsun.bev.lbl.gov
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