diff --git a/src/systems/systems.jl b/src/systems/systems.jl
index 2ac0c3d5d7..29f7c7b94f 100644
--- a/src/systems/systems.jl
+++ b/src/systems/systems.jl
@@ -19,9 +19,11 @@ topological sort of the observed equations in `sys`.
 """
 function structural_simplify(
         sys::AbstractSystem, io = nothing; simplify = false, split = true,
-        allow_symbolic = true, allow_parameter = true, conservative = false, fully_determined = true,
+        allow_symbolic = false, allow_parameter = true, conservative = false, fully_determined = true,
+        kwargs...)
+    newsys′ = __structural_simplify(sys, io; simplify,
+        allow_symbolic, allow_parameter, conservative, fully_determined,
         kwargs...)
-    newsys′ = __structural_simplify(sys, io; simplify, kwargs...)
     if newsys′ isa Tuple
         @assert length(newsys′) == 2
         newsys = newsys′[1]