Hello,
Your Hot Water On Board system is so nice and professionally built. You are the only 5th Gen 4Runner owner, who I found , installed such a clean solution. I am (a non-tech guy) planning to follow the same path to build the similar system in my 4Runner. May I seek your valuable experience about this project?? :
1. Is there any potential risks in terms of mechanical failure (e.g. coolant leaks, pressure level reduced, heat exchanger too hot & cause fire, engine overheat……..) for this modification? Please give comments about the potential to compromise the durability of the truck.
2. There is a potential risk to MODIFY (not add) the engine system and it could void the manufacturer warranty?
3. Can you get “warm water” even though the engine is in idle running (e.g. 800rpm) and water temperature “can be increased” by something? How can you control the water temperature? Do you need to increase the rpm or change the air heater level inside your 4runner?
4. Any potential issues for the heat exchanger to be cracked/damaged during winter freezing season, some water was left inside, right?? What are you going to do in winter time?
5. Connection method :
I look under the hood, there are 2 pipes (coolant flows through them) of core heater hose going through the firewall into the vehicle. Do you know :
Upper Pipe (Coolant returns from the heater) ??
Lower Pipe (Coolant flows into the heater) ??
Certainly, it can be verified by touch them to see which one is hotter (flow into the core heater). But this is not scientific, could be wrong !
Where did you connect with the Core Heater Hose? Are you connecting in series with the heater core hose? Are you using the in-path (i.e. coolant flows into the heater core) or out-path (i.e. coolant return path from the heater core)?
6. What connector types/size (in the heat exchanger) would be the easiest for non-tech person to carry out this project in the 5th gen 4runner? E.g. ½” Male NPT, ½” Hose Barb, 3/8” Copper Sweat….. I want to choose the simple connector types of the heat exchanger to match the hose dimension. I want Plug and Play method if possible.
7. I intend to connect the heat exchanger in series with the coolant return path (i.e. after coolant going out from the core heater unit). Then, I just need to disconnect one hose to minimise the change. There is no impact on existing core heater for its heating performance. I can also control the water temperature with the core heater knob (coolant flow rate) inside the vehicle as well. How would you comment this configuration?
8. What is the dimension of the core heater hose that I should buy?
9. After installation: I need to refill coolant (there may have some lost by redirect it to the heat exchanger)? How can I verify the existing core heater (hot and cold air blow out from it) still functioning as before? For those professional mechanics, do they have any tool to check the coolant pressure/level, heater performance??
Looking forward to share your valuable experience with ALL 5th Gen 4Runner owners !