eel grass is BAD
I've idled in eel grass many times, and never got plugged to the point of melting a exhuast coupler! if it over heatsm clean the strainer, this stuff hung up just before the steering fluid cooler and impellor.
You would not think that that much grass would go through the water pick up on the front of the leg. Did your engine alarm and shut down?
I hit some wood once with my D4 and broke the water pickup plate. Pieces of the wood went right into to my impellor and tore the blades up.
I only noticed this when I got it back on the trailer, the engine temp was not really effected.
I grew up fish on my dads boat and he always said watch the gauges and trust the compass!
I saw the temp gauge up to 210-220 and chopped the throttle and the temp dropped, (clients said the alarm went off when I chopped the throttle) when I would go to 2000rpms it would over heat, I kept it below 2000rpms, then we smelled smoke and found the source, the next the day I found the plugged pipe!