Coolant passages on 3b

[peteinjp]

In my bj46 with the 2 batteries under the hood there is not much room for the coolant heater. I'm thinking that if there is not a problem with running the heater circuit from here I might have my solution.

Is this not at the end of the coolant circuit as the coolant cycles back to the water pump? If so I would run from here to the coolant heater and and run a second pipe from the coolant heater on top of the heater return pipe back to the heater intake pipe at the firewall. I would also plug the original heater outlet from the back of the head.

Is this an Npt fitting?

if I add power steering will this hole be obscured?

Also if any had any concerned about this placement (will be lower than it is now under the stock air filter housing) in regards to adding a turbo I'd like to hear about that.

Thx-

Pete

 

[John Galt]

These lower rad hose heaters work better, take much less space:

Canadian Tire ZeroStart ZeroStart™ Lower Radiator Hose Heater : Questions, Answers, How To, FAQs, Tips, Advice, Answers, Buying Guide

 

[peteinjp]

That will not heat my cab with the engine off and requires a 120v power source.

I need both an engine preheat as well as engine off cab heat.

It is an easy install though.

Pete

 

[peteinjp]

Does anyone have a diagram of the coolant flow?

Pete

 

[lostmarbles]

This is what I worked out on my engine Pete:

PS. This is a B but I'd expect a 3B to be the same.

 

[peteinjp]

Thanks Tom,

So the hoses in the left side of your pic are to and from an oil cooler? I don't have those on my 3b.

Your pictures are solidifying my thought that the plug I pointed to in my first pic is indeed towards the end of the cooling passage in the head. Do you have that plug on the B? I wonder what it was originally for....

Pete

 

[618Henrik]

the plug /hole is there originally, it will not be obscured if you add powersteering.
Sorry for the poor pic.

 

[lostmarbles]

Thanks Tom,

So the hoses in the left side of your pic are to and from an oil cooler? I don't have those on my 3b.

Your pictures are solidifying my thought that the plug I pointed to in my first pic is indeed towards the end of the cooling passage in the head. Do you have that plug on the B? I wonder what it was originally for....

Pete

Hi Pete

Yes those hoses are for my oil cooler. I forgot that the more elaborate oil cooler on post Aug 1980 B-series engines (like the 3B) did away with them.

I don't know what purpose that plug (or the hole it seals) serves.

Yes it does appear to be a coolant-location at the end of the coolant passageways (just before the pump/thermostat combo takes the fluid again for recirculation and/or cooling).

I do recall that some owners who's tried to remove that plug have had tremendous difficulty and have ended up rounding off the "square" rather than unscrewing it. So beware..

I'm not sure if the plug gets this tight from corrosion or whether Toyota used a very hard-locking sealant..

 

[peteinjp]

Sounds like the plumbers torch may come in handy!

I may try running the coolant heater thru the block first with the line that comes back to the top of the water pump but I'm not sure how well it will heat the cab- or rather how long it will take to heart the cab.
Thanks again For the info.

Pete

 

[Patrick Cyrenne]

Hi Pete do you have a picture of your final installation. I try to figure where i will connect the two coolant hose. Thanks