Block heater experience?

I have one and a transmission pan warmer from JC Whitney. I found they were most useful for an hour in the morning when temperatures were below 40F and especially below 32F. But it really depends upon what local, warm-up routes are available.

Warm-up: maximum idle in "N" while moving

I have a 1.5 mile, neighborhood route posted, maximum speed of 25 mph. When the temperature is below 50F:

• accelerate - modestly, 2,400 rpm or below, and once my target speed is reached, shift into "N"
• moving - shift into "D" to reach 27-30 mph and then into "N" while the engine idles and speed decay
• decellerate/stop - shift into "D" for regen when coming to a stop sign or light
• stopped - hold with brake and shift into "N" to minimize fuel burn at idle

This warm-up protocol maximizes running at engine idle in "N" to defeat engine driven traction battery charging, a minimum fuel burn, while continuing to move. It takes 5-6 minutes with a radiator block, to get the engine coolant close to 70C where hybrid operation can begin.

Installing the block heater is awkward. One approach is from the top but you'll want small hands. Another is reach up from the bottom, after the car is raised on jack stands. The car needs to sit 4-6 hours to let the exhaust cool. Just keep telling yourself "I only have to do this once." Take care to tie-wrap the power cord(s) as any vibration, especially with the transaxle pan heater, will break the wires, and replacement is twice as bad.

Other cold weather tips:

• scangauge II - for instrumentation, especially the ICE coolant and ICE rpm
• tire pump - you want to keep them fully inflated which go soft in the cold

Bob Wilson

 

We use ours year 'round. I've got it hooked up to a timer that goes on at 6am, off at 10am. My wife's the primary driver, and typical weekdays takes off around 8am. Sometimes earlier, sometimes later.

Weekends almost without fail I hook it up for a couple of hours before first start, sometimes a lot more, since my guess at our departure time isn't alway accurate.

We had it installed at time of purchase so haven't compared with/without. Our winters are pretty mild, and using it through the summer gets me some looks.

I figure even though it's more crucial in winter, any time of year it'll raise your coolant through 30~ degrees centigrade, which means the car starts auto-stopping and various other hybrid behaviours a lot quicker.

 

Pool water-noodle toy cut to length and split on one side. Use small diameter bungie cords of same color to hold on.

Bob Wilson

 

Read that about 6 times before the lightbulb went on, lol.

3/4" foam pipe insulation (that's inside diameter) also works fine. I use some velcro strips I bought through Lee Valley, designed for holding plants to stakes, but works well.

 

Pipe insulation, swimming pool noodles, or a curtain of vinyl stair-tread protector.

-Chap

 

I had gotten my instructions via various search functions and an engine sketch showing the location. It is a pain-in-the-nice person to install. The general approach:

1. Cold engine - reach behind the engine on the right hand side and feel down on the block between the engine and firewall. Try to find the hole and a block that the latch connects to. You can't see the installation hole, it has to be felt. From the bottom, with the car raised, again, reach up to feel/find the hole. THIS HAS TO BE DONE FIRST.
2. Practice getting part to hole BUT not in - you want to 'learn' how to get it to the hole but NOT IN until you know you can get to it.
3. Take a break - no need to get anxious on the next critical steps.
4. Make sure you can get the part to the hole . . . do not seal!
5. Small goop the heater on one side - the thermal compound will form an air-tight seal making it as difficult to install as a piston in a sealed cylinder. Gooping on one side provides a channel for the air to escape when inserted.
6. Insert the heater probe and rotate to 'clip' it in position.
7. Run power cable forward and locate where you want the extension cord to go.
8. Tie-wrap paying attention to potential vibration sources and use extra ties as needed. Copper will work harden and insulation can wear so take your time. You don't want to lose the heater because the power cord 'broke'.
9. TEST: I use a Kill-a-Watt, an inline meter, that shows about a 400-500W load and plug in extension. You can also carefully feel around the part. The heater gets hot FAST like an iron but the metal around it takes a little longer. You might also feel the insulated power cord near the heater as it will also get warmer.

I found the block heater works best in 40F or cooler weather for about 30 minutes to an hour. So one bracing dash to the car to plug-in the heater and back in the house for a cuppa coffee, getting dressed, and the last of the morning news. Don't forget to unplug the heater and have a happy.

Bob Wilson

 

There used to be a poster in this forum (Wayne, posting as FireEngineer) doing the Johnny Appleseed thing for block heaters. Still at it four years ago, anyway, last I knew. If you knew when he'd be passing by your location, he'd have your heater installed in about 5 minutes flat.

-Chap

 

The block heater comes with a little tube or packet (I forget which) of thermal conductive grease. The heater needs to be coated with this grease before you install it in the engine block for real (your 'dry runs' will probably be easier, well, dry).

Without the grease, heat will not be transferred effectively from the heater to the block, and the heater itself may overheat and burn out.

If you obtained your heater somehow without installation instructions, did you also obtain it without the thermal grease? If so, I am not sure exactly what the OEM thermal grease is. Stuff at your local computer repair shop for CPU heatsinks might do the trick.

-Chap

 

Mine was in the box. But if missing, any electronics store would carry thermal compounds that would work as well. Just try to leave an 'air escape channel' when you do it 'in real life.' Otherwise, you will be unhappy.

BTW, I have long arms. Of the two installation approaches, I like going from the bottom (because I'm laying on a blanket on the ground.) From the top is best for people with smaller, more nimble hands.

Bob Wilson

 

Engine block heater installation organized by Milwaukee Hybrid Group - Milwaukee Commuter | Examiner.com
Engine block heater (41H) - Page 8 - GreenHybrid - Hybrid Cars
Shenandoah by Prius (go to 'day 6')
Yet another block heater installation thread | PriusChat
Prius heat-efficiency mods

Also:
So I figured out how to install my block heater | Page 15 | PriusChat

Bob Wilson

 

Both use the 1NZ-FXE engine so the mounting hole should be in the same place.

It's on the transaxle end of the engine (the left, if you're facing the same way the car does, the right if you're standing in front of the car facing in. In other words, it's near the midline of the engine compartment. If there were no big honking inverter mounted next to it, it would not be so hard to see.

-Chap

 

Take time to route and anchor the cord, especially from the heater until it reaches 'easy access' places. I know of one block heater that had the cord fail at the heater. If you think installing is painful, try to take one out!

The power cord is multistrand copper and is fairly tolerant but copper does like to 'work harden.' The less vibration it experiences, the better.

Bob Wilson