Masato

I would hate to slice a 'T' there and then find myself somewhere far up the creek.... you know it would just me my luck too.
Cdn Bacon: I'm not specifically trying to keep the rad warm - that's just a result of tapping the lower rad hose. The whole idea behind the inline heater is to keep the block warm by circulating heated coolant. It just so happens that I can't use the block drain hole and the oil cooler hose is in a pretty tight spot so my options are somewhat limited.

Canadian Bacon

It was my understanding that the coolant will stay cool in the whole system. Am I right in saying then that the heater will heat the fluid going into the block but, once recirculated, will become cooled when it flows through the rad. Therefore, the heater must re-heat the fluid continuously?

mt_goat

That's what I'm picturing. I had an in-line heater in a Honda Accord once (late 70's) living in Aspen. That thing would start-up and the heater was warm already, pretty nice. It was a simpler design though, you spliced it into the heater hose and the pump just pushed the heated fluid around. The inlet and outlet were in the same hose.

Masato

Just a quick update and thanks to all who chimed in. The heater is in and working great in this sub freezing weather we've been having. Mt. Goat: Thanks for the great reference pictures. I ended up 'T'ing in to the oil cooler line. Since I had to get in there and replace my T-belt and water pump anyways, it was fairy easy to work in there. From what I can see, its working just fine. Again, thanks for the ideas and reference pics.
Cheers.

mt_goat

Great