How to keep an efficient engine warm?

[Isaac Zackary]

Originally Posted by oil pan 4

Get a block heater or 2.
That is the fastest easiest way to do it.

Originally Posted by redpoint5

...Can you put a higher wattage block heater in? An oil heater would help too...

Ok! I'll see what I can do to add a tank style block heater on the Avalon. I've used 1,500W tank heaters on my other cars before and they work great when you can plug them in. Not a solution for where I can't plug in, but not so expensive that it wouldn't be worth it for where I can.

Let's see here. I believe the current block heater is 200W. If I got a 1,000W tank heater that would be 1,200W. With 50 to 100W for the oil pan heater I'd still have some juice left (using a standard outlet) for a battery heater for both the traction battery and perhaps the 12V battery.

Originally Posted by redpoint5

I personally wouldn't idle to warm up.

Get a temperature gauge so you know what coolant temperatures are doing, and set an alarm for some upper limit, like 215 F. Then grill block in a way that you can quickly add/remove it. I use foam pipe insulation wedged in the grill slats.

…

You could add insulation to the engine, like a blanket or something, to retain more heat.

Originally Posted by ThermionicScott

Assuming we're talking about the Avalon and not the VW, get a Scangauge/Ultragauge/Torque app or whatever so you can watch the coolant temp, and block the crap out of your grille!

That would be a good idea. I'll see what I can do to get an easier to read gauge and perhaps a light of some sort. I guess foam wedges would work just fine, at least for now. I think I'll go get some pipe insulation right now.

I bet I could run around town with it completely blocked off. And when I go on the highway up mountain passes, I could figure out how much blockage I need to take off to keep from overheating with the temperature gauge.

I'll see what I can do about a blanket too.

Originally Posted by oil pan 4

I put a little space heater in my cars.
In my leaf it deices the car and makes the ride bare able with no heat.

Yep! I've been doing that too at home. When I had my Leaf I would use the preheat function with the car plugged into a 240V source.

Originally Posted by Ecky

My Insight suffers from this as well. The engine even has exhaust heat recovery - there's a water jacket over the exhaust. When it's below freezing and I turn on cabin heat, I start losing coolant temperature, nevermind when it's 20 below zero. Cabin air recirculation helps but then my windows fog up. A 100% grille block helps, but isn't enough. Pre-warming the engine helps, but doesn't stop it from cooling back off after I'm driving.

And before you ask, my thermostat is fine, it's only when running heat.

I know right! With the Golf I was having that problem. Many said it was the thermostat, but I knew the thermostat was fine. It was that tiny diesel engine that couldn't keep up with the cold. On the Avalon it warms up quicker and better and stays warm so far. We'll see what it does at way below zero. But on the other hand it still takes time to warm and it uses much more fuel to do so. Plus, once it has warmed up the engine will shut off until either the hybrid system says it needs more engine power or until the engine cools down to a certain point. So the warmer I can keep things going the less fuel it should use.

[Lemmy]

Originally Posted by Isaac Zackary

So I have a 1985 VW diesel. So far I've been getting upper 50's (mpg US) on the highway. But the problem I've been having is warmth. Even during the summer our town is so small that if I drive to the store, work, anywhere in town, it's so close that the engine does not warm up to running temps in that distance. To make matters worse winter temperatures here are constantly below freezing and can reach well below zero Farenheit for most of January sometimes reaching as low as -40° F. This not only makes me a bit unconfortable (ya, I wear long johns, sweater, coat, hat scarf, gloves, boots, the works!) but it also worries me for the engine's sake. I'm sure that it's not good for fuel efficiency nor the enviroment when I'm billowing out huge clowds of white and black smoke as it warms up. I've got it adjusted so that it hardly smokes at all at full throttle when warm (only when at high RPM and full throttle). But all that smoke when the engine is cold indicates that much of my fuel is not burning completely or at all!

I think part of the reason is that my engine is a bit too efficent. With a 23:1 compression ratio I think it converts too much fuel into power instead of heat. I've tried new thermostats, different temperatures, grill block offs, and a block heater. My current block heater is a 1,600 circulating tank heater that does a very good job, if I'm where I can plug it in. But when I leave the car at work and other places it cools down fast. Now what?

So instead of using 0W-20 to keep my oil pressure from blowing my oil filter, wouldn't it be nice to have a way to warm and keep warm my engine? I'm throwing a couple of ideas out there. Any other ideas would be welcome!

Passive solar block heater
So I've been thinking of plating below and around the whole engine. I'd leave a space in the back where air from the radiator can exit. Also I'd like to keep the radiator blocked off, at least during winter. Automated louvres would be nice! Besides that I was thinking of cuting a large part out of the hood and placing a piece of glass in it. I might coat the whole inside with aluminum foil. With the black engine all that light should reflect on it and keep it warm, at least during the day.

Exhaust coolant heater
I was also thinking of using exhaust heat somehow to heat the coolant. There are few ideas to this. One would be to just place one piece of tubing along the exhaust down pipe and re-route the heater hose through it so that it doesn't overwhelm the cooling system during summer use. Another idea would be to have the exhaust pass through a heat exchanger, maybe a modern TDI EGR cooler, and have an exhaust valving system that bypasses the heat exchanger once operating temperatures are reached.

Also there are two coolant sources on my engine for this. One is the cabin heater coolant circuit, which passes back near the exhaust system. This is constantly flowing, although probably not as much as the cold bypass circuit does when open. The cold bypass coolant circuit is on the front of the engine and it circulates coolant until the thermostat opens the radiator circuit completely, at which point it shuts off this circuit. This could be routed to the back of the engine.

Of the two each has their pros and cons. The heater does not have an air recirculating feature, so the coolant running through the heater is obviously going to be cooled quite a bit. So it makes sense to reheat this coolant as much as possible. On the other hand it is constant whereas the cold bypass circuit shuts off when hot. Yep, if I did have an overheat situation, this would generate steam at the heat exchanger. But as long as the thermostat is working, at least it would not continue to circulate coolant through the heat exchanger.

I kind of like both ideas. But maybe someone else has a better idea. What's your thoughts?

For journeys of that nature I use my bicycle to avoid that very problem. Diesels are bad polluters for nitrous oxides and particulates, which kill 20,000+ people a year in the UK, and when they're cold they're particularly nasty.

[Isaac Zackary]

Originally Posted by Lemmy

For journeys of that nature I use my bicycle to avoid that very problem. Diesels are bad polluters for nitrous oxides and particulates, which kill 20,000+ people a year in the UK, and when they're cold they're particularly nasty.

You ride your bicycle in weather that's between -40°F (-40°C) to 0°F (-15°C) in blowing snow at night?!

[Ecky]

Originally Posted by Isaac Zackary

You ride your bicycle in weather that's between -40°F (-40°C) to 0°F (-15°C) in blowing snow at night?!

Night, which is 16+ hours per day here for part of the year. ;(

[Isaac Zackary]

I've often pondered making a bicycle or tricycle that has a body and a heater for my short drives. I'm not sure how well it would ride through the snow though.

[19bonestock88]

I stopped riding my bike when temps got below 32F... I just wasn’t equipped to handle the cold, if he can ride in -40F weather (though I doubt it gets that cold in England) he’s more of a man than I

[me and my metro]

Back in the mid 80s I drove a B210 with a 1.3L and a 5 speed. The little car was efficient and got 42-43 mpg in the warmer months. In the winter in Central Oregon the air blowing through the grill would cool the engine to the point that the choke would start to close. The thermostat worked fine but the heater would cool the engine. Probably a grill block would have helped. I solved the choke problem by removing the temp control on the air cleaner and running the car on hot air off the exhaust manifold. The heater would still cool off the coolant but I could put the car in 4th gear for a while and it would warm back up.

[Lemmy]

Originally Posted by Isaac Zackary

You ride your bicycle in weather that's between -40°F (-40°C) to 0°F (-15°C) in blowing snow at night?!

Yes. My coldest commute was indicating -28 Celsius when I lived in Pennsylvania, although the weather boys reckoned it was only -21. Blowing snow is no problem, only becomes an impediment when its settled on the ground, in which I wouldn't take to the roads at all unless there's an SAR callout. Trust me, as a big feller I'm much happier in the cold than the heat! Its the purest pursuit of wheeled fuel economy.

Cycling in the snow is great fun and a good way to develop your control skills (I'm an MTB skills instructor), and viable means of transport. The bike will go in any conditions the average 2wd car will go. However, as aforementioned, I stay off the roads entirely if I can by that point because of all the brain donors slithering about in their cars like drunk dodgems.

Once you've unsuccesfully given CPR to a 13 year old girl having a severe asthma attack who died in your hands, then you start to get a little bit conscious of unnecessary air pollution in the urban environment. I'm not having a downer, just offering the method that works for me in the OPs situation, one so obvious that most folk overlook it (or requiring so much effort that many folk can't be arsed to consider it) that doesn't produce nasty pollution just where you need it the least.

Short of garraging the car when not in use and pre heating the coolant and sump I can't see any obvious, pactical solution to the Ops scenario

[ThermionicScott]

Originally Posted by Isaac Zackary

You ride your bicycle in weather that's between -40°F (-40°C) to 0°F (-15°C) in blowing snow at night?!

He has a point in the spring/summer/fall, regardless.

[19bonestock88]

Agreed... people should consider doing a human powered transport in weather that the power source can tolerate... I saved probably 5 gallons of fuel in my car by riding my bike to work this summer/fall... also saved countless cold starts and about 200 miles during which my engine never would possibly reach full temperature, even with a heavily blocked grille...