I realize this threads fairly old but I just wanted to offer my experience having just installed a block heater in my 2017 CR-V. Before I did it I looked all over on the web and didn’t find anything very helpful in terms of practical advice on how it’s done, except for the Honda installation instructions which tell you to remove the entire front bumper. Turns out the only reason to remove the front bumper is to route the chord, which I found was totally unnecessary as it was easy to do cleanly and securely beneath the hood instead.
The only special tools you need that you may not already have are a 24mm socket for installing the heater, and a 24” breaker bar for removing the old plug. I also printed out a copy of the Honda instructions to reference along the way.
First, drain you coolant from the radiator. I saved mine for re-use since there’s not that many miles on it yet.
Next, disconnect the negative battery terminal and remove the air cleaner and intake air duct as per the Honda instructions. After you remove the required bolts, you’ll need to pull up fairly hard to release it from the pin.
Next loosen the plug in the engine block with a 19mm socket and 24” breaker bar. This is the hardest part, I had to put a lot of force to get it loose, even with a 24” breaker bar, so make sure your socket is properly seated on the bolt. Once you get the plug out, almost a gallon of coolant will come gushing out (even after having drained the rad). I didn’t reuse this coolant, as it falls all over the frame, collecting dust and salt along the way.
Next, install the block heater, plug it in, and route it as per the installation instructions, up until you get to the top of the engine compartment. Instead of going back down to the bottom of the bumper, you can bundle up any excess chord to the right of the air cleaner, zip tie it out of the way, and bring the chord end out wherever you choose (I found that it worked well to fish the block heater end of the chord into the engine area through the opening next to the hood release prior to plugging it into the block heater. My chord now sits centred under the hood, right at the hood release. I think this is better than Honda’s way of doing it, bucause I can tuck it back in under the hood for protection in the summer.)
Now reinstall the air cleaner, connect your battery, and fill up your coolant reservoir (after closing the drain plug of course). Use a gallon of new coolant, plus as much of the coolant you drained from the radiator as you need to top it up. Honda makes it very easy to bleed your coolant in this vehicle, you just need to keep adding as the engine warms up, then check coolant levels after your next few drives as it bleeds itself.
One final point, the Honda dealer where I picked up the parts told me their technicians use 1L of coolant to do the job. They must be reusing the stuff that drains all over your frame, I highly recommend buying a full gallon, or even two if you want to accomplish a full coolant change at the same time as the block heater install.
That’s it, as you can see it’s not all that difficult since you can do everything from above, and it saved me about $200 in labour over having Honda do it. I hope someone finds this helpful!
