[Insightful Trekker]

It has long been discussed here about adapting the Toyota Prius's hot coolant thermo bottle to the Insight. This will reduce warm-up time and increase MPG especially for those doing mostly city or cold climate driving.

I've recently found a new paper released on the Prius similar to the studies done on our Insights.

601.6Kb .pdf file

http://www.ornl.gov/~webworks/cppr/y2001/rpt/121813.pdf

pg. 15 fig. 2.3 diagrams the cooling system with a narrative description.

See my webpage 3 for a better view of this pic if needed. I'll keep it up for a few weeks. If your interest is greater I'd recomend getting the entire .pdf

Glad Honda chose a more elegant design!


It looks like a complex mod which will require some type of control system to be designed to make its operation automatic. Manual control would be relatively simple. I am somewhat concerned of an increased thermal "shock" to the metals. If this hot water is simply "dumped" into the cooling system on a cold engine the thermal expansion stresses will be greater than the normal slower warm-up time. Perhaps the 3 way valve that Toyota uses restricts flow to help limit this concern.


Dimensions are probably also a concern. The only available space for something that would approach the size of a 3 liter thermos bottle is to modify the battery tray and limit 12v battery size to a Hawker instead of the standard replacement Civic battery.

Can anybody get these dimensions and the size and location of the plumbing connections?

And finally cost is probably the limiting factor. It sure looks like it will be expensive! And I haven't had the time to call a local dealer (and brace myself for the shock <VBG>).

Will anybody else follow up on this?


Better ICE thermal management in cold weather is the trick for MPG improvement in our Insights. I recently monitored my ECT while in a slow and go Interstate jam-up. In mid 40F ambient the ICE chilled to 180F while slow and go from 5-35 MPH. I wasn't even sitting in auto stop except twice for only a few seconds.

Some type of automatic air flow control in front of the radiator would be the key. Basically be able to totally block flow until warm-up has occurred, incrementally open / close to regulate chilling in low fuel consumption conditions, and open fully when air flow over the condenser for A/C operation is needed.

Still looking for that perfect item to do the job.

Perhaps the biggest problem in acomplishing a complex mod is to remember that cost is always a consideration except in NG discussions and dreams.
<VBG>

HTH!

 

[Yves M.]

Hello John, do you think that the diagram is correct. Could it be a simplistic explanation of a more complex design.

I write this because if you take out the section for the hybrid gear which is separate in flow, the engine section does not seem correct. It shows the engine / cooler pump and radiator to be in series. As if the coolant could only be pumped through the radiator.

In a normal car, the thermostat is used to either have the pump circulate the flow within the engine (never into the radiator) for warmup
or the flow goes through the radiator for cooling down

I do not see this in the diagram so I think that they provided only a portion of the diagram.

In our car, if you where to put some bottle in like they show, the flow would not go through the bottle until the system is already warm. You would need to remove the thermostat and figure something else to permit a bypass only within the engine or with the radiator added

Addition:
So i think that what you need is to put the bottle exactly where the radiator is in the flow (remove the radiator). Then you need two things:
1- A way to provide the bottle into the flow at startup. Only if the bottle is hotter than the engine. Bypass of the thermostat then.
2- A way to put the radiator into the flow once the coolant temperature reaches the necessary temp. An remove it once the temp has lowered.

 

[Insightful Trekker]

Hello John, do you think that the diagram is correct. Could it be a simplistic explanation of a more complex design.

<snip>

I believe the diagram to be correct for what it represents. But it *is* incomplete as to the whole cooling system. The thremo bottle is in parallel to the shown part of the cooling system with a valve and a _seperate_ pump to allow flow through this branch.

The engine thermostat is not shown. And the flow direction arrows appear misleading.
[edit:standard water pump *IS* shown, flow arrow sentence added]

I've read somewhere (maybe in this document) that the Prius radiator is a triple combination of standard radiator, hybrid drive radiator and AC condenser. One piece with the three separate "radiators" sandwiched together!

Bumper bash ups will be big bucks! ($,$$$)

HTH!

 

[Guest]

Hi Insightful Trekker:

___Instead of a thermos, have you considered an electric engine block heater run off the Pack via timer with limitations on both current draw and a total draw so as to not come back to the car with a drained pack? It sounds like a far simpler solution then the Prius Thermos solution. It wouldn’t work over 3 days as the Prius thermos is supposed to but even the Prius’ thermos probably loses ~ 50% of its heat capacity within the first 16 hours or so. Since our little beauties are in the cold at Home, work, wherever, and we know the ~ time we will be taking them to the next destination (Home, work, wherever), maybe a timer for 1 hour before ignition would do the trick. It would also be far less costly and less technical of a mod by all appearances?

___This is one area where a nice sized solar panel might provide all the power needed to keep the coolant warm during the day through an engine block heater in the middle of winter?

___Good Luck

___Wayne R. Gerdes
___Hunt Club Farms Landscaping Ltd.
___[email:2nhxg3uz][email protected][/email:2nhxg3uz]

 

[Insightful Trekker]

C'mon Wayne,

I though you are up to speed (not exceeding 55 though <g>) in regard to the small amount of electric power in the IMA pack. Aint nuff back thar fer a heater. <g>

Nor will a solar panel provide sufficient electric energy. You'd do better to use the interior as a greenhouse. Circulate this warmed air through the heater core and use a solar panel to drive the fan and a small coolant pump. Even then the amount of heat transferred and remaining as engine "pre warm" will be small.

I've got a block heater installed and have used it on a few occasions. But I do park in the driveway and messing with 110v in the rain is *dangerous*. Nor have I gone to the correct trouble of wiring a switched, timed outlet to allow efficient and safe use of the block heater under my common use conditions. But its on the to-do list.

 

[Yves M.]

In the same line of thinking, although it leads to better "Environment" and not in the "free heat" of no gas usage for it:

A second 12v battery ($70) , a 120V inverter ($110) and a recreational vehicle " battery separator" could make for a 12V electric heater. I do not know how much time it could produce heat but it would not deplete the 12V battery of the car or the IMA battery. Installed in the rear passenger side empty hatch area.

But the heat would come out of the gas and not from the free excess engine heat. Not that there is much excess here. It is better for the environment.