18RGEU Overheating

[Spectre]

Just fixed the spark problem I was having. (Required new toyota dizzy cap, new leads and spark plugs). But now I'm having really bad overheating problems.

I havn't driven it yet, ive simply had it idling, and once it reaches running temp, it just continues to rise! Ive only let the temp guage get just over half way before turning the car off.

The water in the overflow bottle was bubbling and boiling at one point, and coolant began to seep from one of the rear taps on the engine. May I have the hoses connected wrong? On the fire wall, the "Left" outlet is plugged to the "Front Tap" on the engine. The "Right" outlet on the firewall is plugged to the "Rear Tap" on the engine.

The radiator was recently flushed.

Is it possible that the thermostat housing is jammed shut? If so how do I go about testing this?

Any other idea's?

Cheers,

Bryce

[Spectre]

After searching through some 18RG shots, I think I have put the hoses on the wrong way

Is this how its supposed to look?


This is how I think ive done it (red arrows are joined to one other, blue to eachother) basically to the wrong taps on the engine..!


Could this be the cause of my overheating issue?

[river]

Hi,

Looks different to mine.... but, the long hose goes to the bottom inlet pipe on the firewall, and the little hose (from the rear of the engine) goes to the top inlet pipe on the firewall. However, my car is based on the TA22 and it looks like your arrangment is different. So, maybe someone with a RA23/28 would be best to tell you what their set-up is like.

I am not sure what happens if the hoses are in backwards. If there's a valve set up in the heater core than maybe it might stop the water flow, but I would assume there would also be water flow going through your engine regardless. But, you never know.

One thing you can try, and I've done it once and it worked (when I split my heater core) is to connect the long hose into the the back of the engine where the little hose comes out. This bypasses the heater core. If you can do this and it still overheats then I'd be looking for something else causing the problem.

seeyuzz
river

[The Witzl]

Spectre,

The water system is simple.



Start at the waterpump.....

1. the 5/8" outlet pipe that goes toward passenger guard above the alternator should have a T'ed in outlet on it, so it effectively has two outlets. Note the green arrows.
2. the first of these two outlets (one pointing towards the front of engine bay) connects to the thermostat housing.
3. The second of these outlet in point 1. connects to the drivers side outlet of the heater core at the firewall
4. the other outlet of the heater core connects to the heater valve tap rear pipe
5. the front pipe of the heater valve tap connects to the outlet on the head just near exhaust port from cylinder 4.

If you have done this, and you are still overheating then you have a problem with your radiator, fan, or water system inside the engine (water pump, water galleries blocked, etc).

Now if you have NOT connected point 2 to the water pump, then your thermostat may possibly not open. This water line is a "bypass" that takes the hotter water from the water pump and sends it to the thermostat so that the thermostat can open at the correct temperature - otherwise it would be sitting in water that hasnt fully heated up yet.

[The Witzl]

One thing you can try, and I've done it once and it worked (when I split my heater core) is to connect the long hose into the the back of the engine where the little hose comes out. This bypasses the heater core. If you can do this and it still overheats then I'd be looking for something else causing the problem.

seeyuzz
river

That does work also, but really only useful if you have a leaking or blocked heater core.

[Spectre]

Hoses were connected together correctly.

Checked thermostat, replaced it, its working.

Still overheating, so got a BHG check done... Its fucked.

[twentyEight]

Still overheating, so got a BHG check done... Its fucked.

Can somebody please tell me what a BHG is...

I've never been able to work it out, and I know that as soon as somebody says what it is, I'll feel like a knob! (or is that a n00b)

[AusRA28]

BHG
Blown Head Gasket

Dave

[Spectre]

Can somebody please tell me what a BHG is...

I've never been able to work it out, and I know that as soon as somebody says what it is, I'll feel like a knob! (or is that a n00b)

it's something you DONT want to have! Specially on an engine that you brought not long ago and havn't even be able to drive yet

[The Witzl]

it's something you DONT want to have! Specially on an engine that you brought not long ago and havn't even be able to drive yet

Genuine Toyota head gasket, $58
....
profit.

[Spectre]

Ive got a head gasket, came in a complete gasket kit I brought.

Will just replacing the head gasket be ok? Will the head need checking for corrosion or cracks etc?

[twentyEight]

BHG
Blown Head Gasket

Dave

Yep... I feel stupid now!

[Norbie]

Will the head need checking for corrosion or cracks etc?

Yes. Also check for warping.

[river]

Hi,

Yep... I feel stupid now!

Don't feel too bad. If you owned a 7M then you'd know all about them, but being an 18R-G owner you're most used to terms like.... cult-engine, power, reliability, endurance and other wonderful adjectives.

seeyuzz
river

[The Witzl]

Ive got a head gasket, came in a complete gasket kit I brought.

Will just replacing the head gasket be ok? Will the head need checking for corrosion or cracks etc?

brought = to bring something, example: Honey, I brought home a new mistress for us to have a go with tonight

bought = to buy something, example: I just bought an 18R-G, now I am cool


.....as for your BHG, well i would definitely check the block and head mating surfaces, and cant hurt to check out a few other things whilst you are there.

Buy a Toyota 18R engine service manual (aka the green book), as it has all the assembly, disassembly, tolerances, etc etc in there.
Removing the head is pretty easy, you can do it in the car without a drama.

Clean up the block deck with a razor blade and lots of patience, with occasional applications of turps or gasket stripper. If your block is out of spec, then you'll have to pull it out and get it machined.