good/best engine block heater?

[slowmover]

MIght want to fit an engine blanket too; some DIY. I remember reading years ago that these were popular in post-war Japan. Not much money around, and a car of any sort was a luxury. Thus the effort to keep it like-new as long as possible.

Or, a Powerblanket

[tinduck]

At the moment (the weather is getting colder) I am thinking about pre-heating the engine too. But all this block heater / oil pan heater stuff is rather expensive for the lo-tech it really is, in my opinion.

I am thinking along the line of setting up a hot air blower in front of my lower grill. Since the engine compartment is higly encapsulated (belly pan under the engine), the warm air should flow up (as warm air does) through the whole engine compartment before flowing out around the exhaust line to the back of the vehicle. The blower has a 2 KW setting and should kick up quite some heat; I may try 1/2 an hour of pre-heating first and evaluate the result.

Has anybody done this? Thoughts?

so long,

tinduck

[Diesel_Dave]

Originally Posted by tinduck

At the moment (the weather is getting colder) I am thinking about pre-heating the engine too. But all this block heater / oil pan heater stuff is rather expensive for the lo-tech it really is, in my opinion.

I bought my 2 150 Watt oil pan heating pads on Amazon for $26 apiece (including shipping). That's pretty cheap IMO.

[stovie]

what you should do is get a oil heater and a coolant heater, hard wire the two together then put a 120v switch in your car and hard wire a trickle charger after the switch so then you plug in the car the trickle charger maintains the batteries and when you wake up to go to work you flip the 120v switch to run the heaters for 15 to 20 minutes.(if you run a 550 watt coolant heater and 2 150 watt oil heaters for 18 hours at night where i live thats 41 dollars or more a month not worth keeping the heaters plugged in all night if you ask me)

[8307c4]

These pre-heaters are only used in very cold climates when an engine gives such problems starting it in winter I mean the engine won't even turn over, it is that cold.

How do I know, I spent a couple of years in the Rocky Mountains, I won't quite laugh off the New England winter but I can almost guarantee it isn't that cold.
I never plugged mine in unless temperatures fell into the single digits or below.
Windchill doesn't count, straight up single digit Fahrenheit.

The short of it being, you probably don't need an engine block heater, unless...
With a good, fully charged battery, the engine fails to even crank, maybe then.

Because $80 cost of hardware aside I know you will pay more in electricity to pre-heat the engine than fuel it will save, we're talking about spreading warmth in a badly insulated environment that is full of air leaks, the slightest breeze goes right through that engine bay, you couldn't keep it warm unless you dropped a flame thrower under the hood.
Do NOT wrap the engine in a blanket!!!
That is a fire hazard, and the reason I mention it is because I had thought of doing it.

For that reason, for a pre-heater to be effective it needs to stay plugged in overnight, these heaters don't take a completely cold engine and warm it up, there simply isn't enough power in them, not even the most powerful ones (which burn, as one might imply, a certain amount of kilowatt / hour).

The way these things operate is ....
As SOON as the car is parked and the engine is off, you plug it in and leave it plugged in overnight and hope it keeps some kind of meek temperature in the oil.
The engine will still be cold in the morning, one hopes it's not quite as cold.
Oh, we're looking at running a tiny space heater outside in the parking lot for 8-12 hours.

Best kind to get, unless you want to spend hours installing one and since heat rises is a magnetic kind that you can pop onto the bottom of the oil pan, for a more permanent installation you can usually attach it to one or two oil pan bolts with a bracket.
Then run the electric wire through the grill and attach it there some kind of way with a cable tie or tie it up in a loose knot, make sure the electric cable isn't in the way of any moving parts such as fans or pulleys.
Or if you don't bolt it on just pull it off in the morning, might want to wear gloves, the mating surface still does get quite hot.

You may not think so, but doing it any other way is a complete waste of time.

[California98Civic]

I remember single digit (straight-up, no windchill) days in Massachusetts. On those days, ice and snow all around, my 1970 Forest Green 327 Nova would not start without help. I had similar experiences with my 1974 Olds Delta 88 in Jersey.

My purpose in reviving this old thread is for a different reason to apply the heaters. In mildly cold conditions how can they be used to increase efficiency. (I have seen MertoMPG wonderful tests, but he did not test fuel efficiency.) The grid is cheaper than gas, but I wonder if my savings in gas would justify the amount of electricity in mildly cold conditions. Maybe I can run a test with my undergrad students in January. Maybe with and without an oil-pan heater.

Seems the circulation tank design might warm the block better than the oil pan kind and be easier to install than the freeze plug type. But the 750watt ZeroStart circulation tank heater seems quite powerful for my little 1.6L. And I have not found a lower-power circulation-style heater yet. The Kat and the Wolverine units that I found were higher power. Anyone know others that I might be missing? I have seen the kind that fit inline on the lower radiator hose, but Amazon says they are not compatible with my 98 Honda, regardless of the radiator hose size I select.

Any further thoughts?

[puddleglum]

IMO, the tank style heater is the best choice. It uses more power, but it also heats quicker and hotter than other types, so you don't need it on as long. I think the cost/degree temp. rise would be about the same, maybe less. I read on another thread that a member with a Prius can bring his car to full operating temp with a 1000watt tank heater in about an hour. The catch is you need to plumb it into a block drain for it to be most efficient. Using the heater hoses may work on some vehicles, but not well at all on others. That's why I don't have one, I have no block drain on my car.
Overall efficiency will depend on your setup and energy cost in your local area. I did some quick testing last spring (need to do more maybe) , but, it seemed to me that there was no visible overall cost savings in plugging my car in above around 40-50F. That was just my car, though, others may have better results. Also, I have no way to quantify the cost of wear caused by short tripping a cold engine.

[Piwoslaw]

Originally Posted by tinduck

I am thinking along the line of setting up a hot air blower in front of my lower grill. Since the engine compartment is higly encapsulated (belly pan under the engine), the warm air should flow up (as warm air does) through the whole engine compartment before flowing out around the exhaust line to the back of the vehicle. The blower has a 2 KW setting and should kick up quite some heat; I may try 1/2 an hour of pre-heating first and evaluate the result.

Has anybody done this? Thoughts?

Someone has proposed this (I can't find the thread), but it's not the best idea. Heating the air to heat the engine is less efficient than getting the job done directly, mainly because a good portion of that warm air will be lost through holes and drafts in the engine bay. Also, the amount of heat that the engine can absorb is limited by its surface area, so you'd have to keep it in warm air for a long time before it soaked up any heat. You'd spend alot of energy heating everything inside the engine bay, instead of focusing only on what really needs to be warmed up.

A cheap alternative may be one of those infrared bulbs, aimed straight at the engine block.

But if your engine is all bundled up with accessories into a neat, compact package (like mine), then you may not have direct access to the block itself. But the oilpan should be clear, though.

[puddleglum]

Originally Posted by Piwoslaw

Someone has proposed this (I can't find the thread), but it's not the best idea.

I think it was me, and you talked me out of it.

[tinduck]

Mhhh.

Maybe you are right, but in THEORY the warm-air-blower-through-the-lower-grill has some advantages over oil pan or cooling water heaters:

- behind the grill is the water cooler => gets heated. Heat transfer should be great, after all this is an air-water heat exchanger.

- the engine bay is reasonably encapsulated, so the warm air has some time to heat things up before escaping.

- not only the cooling water and the motor block get warmer, also things like transmission and other add-ons will be pre-warmed a little, which helps reduce friction.

Heat transfer IS a question since air is not a good heat carrier. On the other hand, an engine compartment at 0°C or lower provides a steep gradient for air at 40-50°C, so a decent heat flow should be achieved. After all, we are not talking about a blazing hot engine when departing, just about prewarming everything a bit.

I will give this a try since it will surely not make things worse. If it is of no use, I can still let it be :-)

so long,

tinduck