  Given a vector bundle $E$ on a complex reduced curve $C$ and a subspace $V$
of $H^0(E)$ which generates $E$, one can consider the kernel of the evaluation
map $ev_V:V\otimes \mathcal{O}_C\to E$, i.e. the {\it kernel bundle } $M_{E,V}$
associated to the pair $(E,V)$. Motivated by a well known conjecture of Butler
about the semistability of $M_{E,V}$ and by the results obtained by several
authors when the ambient space is a smooth curve, we investigate the case of a
curve with one node. Unexpectedly, we are able to prove results which goes in
the opposite direction with respect to what is known in the smooth case. For
example, $M_{E,H^0(E)}$ is actually quite never $w$-semistable. Conditions
which gives the $w$-semistability of $M_{E,V}$ when $V\subset H^0(E)$ or when
$E$ is a line bundle are then given.
