Had a few chilly nights up here in Canada, plugged block heater in for several hours, didn't heat. Tried plugging it in all night, no response. Usually plugging the glow plug in results in a 7 second glow light on time. I have 1978 300D with the old school loop plugs. These nights it's been a 30 second glow plug light on time. Car still starts fine, but I will be in trouble once December comes. I'm planning on replacing the loop plugs with pencils some time in October, and I'll be going to some form of 5-40 oil as well.

My browsing of the forum leads me to believe that replacing the block heater is an unpleasant task.

Looking for alternatives, kicking around a few options

(1) Zero start or equivelant lower rad heater. Seems like it would be somewhere around a hundred or so for a new unit. Job will be mess, have to drain rad. Plus side is replacing the fluid can only be good for the car.

(2) Put a small electric fan heater in the engine bay. Bonus points if I can have it pointed at the air intake, so the car sucks warm air into the combustion chamber as I crank it.

(3) Wrap a batter heater around the lower rad hose. Is this even remotely smart?

(4) Mount a little basket to put a small flameless propane heater in the engine bay, something like a Little Buddy heater. Plus side is that this can be used to warm up the engine even if I can't plug it in. Downside is buying those little propane tanks all the time.

I suppose I could combine one of (1), (2), and (3) with (4)

Thanks in advance for the feedback