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#1 Drue

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Posted 22 January 2020 - 12:45 PM

Hi guys,
I’ve recently got my Torana on the road only to find it is running hot and breaking down.

What temp should these things run at?
My fans don’t come on until 210 then it cools to 190 and stays between there and 215 when driving. The fans also never turn off.
When it’s hot (30deg +) the car just turns off when cruising and I think the fuel is boiling from the engine being so hot.
Has a 950 quick fuel carb

Setup is
6.0 steel block
Ron Davis radiator With no overflow or header tank
No heater and heater ports blocked.
Edelbrock reverse water pump
Steam pipes linked and run into top of water pump.

Any suggestions?

#2 RallyRed

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Posted 22 January 2020 - 02:48 PM

Hi mate...although you note the steam ports are plumbed back to the radiator....My experience is that the LS engines are cronic air trappers.
Only way to really burp them IMHO is to park them nose up a hill/ on a set of ramps etc, and use a proper radiator filling funnel that seals to the radiator....run it intil warm with radiator full and dribble in the water so that the water level in the funnel is approx 300mm above the engine. Let it burp itself a few times.
Of course, there are a 100 other possibilities , this is just an easy one to try.

#3 rexy

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Posted 22 January 2020 - 03:47 PM

Start the fans at a lower temp like 180f? Are they sealed up so they only pull air through the radiator, not around it?

What fans are you running? A pic of your setup might be helpful.

Do you have a heat gun to check actual temps?

Both hoses seem to be warming up? This shows coolant is circulating. These are easy things to check before you start pulling things off like water pump and thermostat to check them.



#4 grumpy xu1

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Posted 22 January 2020 - 09:54 PM

If you compare it to a vx, the vx runs 2 x 4 wire fans, so both fan's have a low speed and a high speed. You can obviously guess how they would work, personally i think that the steam ports are best running to a high point beside the top radiator hose outlet in the radiator, like Col said, they can be really hard to bleed the air out, even though the filler cap on the header tank is supposed to bleed air out. I always jack the left hand side up, undo the steam line, fill until the fluid comes out the hose & the fitting in the radiator, replace the hose back on, fill the rest of the header tank. Start with the header cap of until the thermostat comes in. Put cap on, test drive. I run ls2 style tridon thermostat, the lowest 1 available in both car's. No problem in Qld traffic. & yes Edelbrock pump to.

#5 gtrboyy

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Posted 23 January 2020 - 09:48 PM

Conversion dudes claim heater bypass is needed instead of blockoffs.

 

They run hotter with higher temp thermostat & factory ls cars run at higher temperatures & water pressure like v6 models.

 

Yeah that hose usually goes to higher point like top of radiator tank.

 

Some models like vz v8 are hard to bleed so some dudes fill them up with boiled water for thermostat to open & bleed.

 

Other thing to do is while running crack loose steam ports to bleed air out a few times



#6 Bigfella237

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Posted 24 January 2020 - 05:43 AM

Setup is
6.0 steel block
Ron Davis radiator With no overflow or header tank
No heater and heater ports blocked.
Edelbrock reverse water pump
Steam pipes linked and run into top of water pump.

Any suggestions?


1. I don't think having no recovery tank is a good idea, especially on an LS engine.

 

With no recovery system there will always be air sucked into the top of the radiator when the engine cools down (because there's no facility to deal with coolant expansion).

 

If the radiator is the highest point in the cooling system then this may not cause an issue, but a Torana radiator is fairly low in relation to the engine and there is always a chance that some of this air will find its way into the heads.

 

2. As gtrboyy mentioned above, if the heater ports are connected normally then some coolant can circulate through that circuit, allowing the thermostat to sense the temperature of the coolant flowing past it.

 

If you just block off those ports completely then there is no circulation at all (depending on whether the thermostat has a little bleed hole of course) and the thermostat will just sit there in a relatively cool section of the system until enough heat radiates through the block to open it (much later than it should).

 

This is especially critical in an LS engine because the thermostat is located in the (colder) inlet side of the system.

 

3. Also I don't like the idea of the steam ports being plumbed into the water pump... Think about it, if the water pump is sucking in air bubbles from the steam ports, where is that air gonna go?

 

Straight back into the engine! There's no way for the air bubbles to leave the block.

 

Any air bubbles should be directed to the underside of the radiator cap so they get pushed out the overflow as the coolant expands.



#7 Drue

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Posted 29 January 2020 - 03:06 PM

Thanks for all the replies guys. I have ordered a bypass hose and a 160 deg thermostat.
Hopefully that helps. I will crack the steam ports and see if air comes out.
I will also look at doing an overflow or header tank if possible.

#8 Drue

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Posted 29 January 2020 - 03:12 PM

https://i.imgur.com/JzYIztW.jpg

#9 ozyozyozy

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Posted 29 January 2020 - 10:38 PM

Id say you have a few issues adding up.
Another thought to consider.
What cube is the engine, 5.7, 6.0? How wild is it?
950 is a big carb for those 2 engines in mild to stock trim, even wild 6.0 its prob too big for cruising with.
If this is so then cruising around town its prob running too lean at low engine speeds, dyno tuners dont normally pick this up. Air speed through carby slows down then doesnt pull fuel into the throats.

#10 grumpy xu1

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Posted 29 January 2020 - 11:16 PM

The steam ports, are simply 2 rectangle blocks, with roughly some 1/4" line joining them & blank at the back, cracking a bolt loose won't do a thing. You leave the hose of, as you are filling it, wait for the coolant to come out & put hose on & clamp. Jack the passenger side up as you fill & bleed the system.

#11 Drue

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Posted 14 February 2020 - 10:11 PM

Engine is a 6.0l steel block with square port heads. 408 cube. Interesting about cruising and running lean.
If I floor it the car sometime stalls when I back off also

Engine is a 6.0l steel block with square port heads. 408 cube. Interesting about cruising and running lean.
If I floor it the car sometime stalls when I back off also

#12 Drue

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Posted 15 February 2020 - 06:54 AM

I fitted a bypass hose this week and went for a cruise last night. Seems to have helped a lot. Temps are around 180- 200 now which is a lot better.
I have twin spall fans which come on around 190 together and never turn off.. It has a 187 thermostat in it. Does anyone know what temp fan switch I should run? Say on at 190 off at 185?
Also would it be better to have the fans twin stage?
Once the car is up to temp if I turn it off and try and start it the fans are always running even when cranking. This doesn’t seem right.

#13 ozyozyozy

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Posted 16 February 2020 - 11:58 AM

The 190-185 switch should be fine, LS engines generally run hotter in there original fitment cars.
Twin stage is not really necessary, it is something you can do when using a/c to help airflow over the condenser.

Sounds like the tune is still not quite right.
I spent a bit of time with my tuner not just on a dyno to get the carb working at low to mid engine speeds, made a world of difference, how often do you actually spend driving around with the throttle pegged to the floor(dyno style)

#14 rexy

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Posted 16 February 2020 - 02:06 PM

You can run an isolation switch to control the fans. Does mean you need to remember to turn them on after you start the car though.



#15 RallyRed

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Posted 16 February 2020 - 06:51 PM

just back to basics...the fans are running the correct direction for where they are?.
i.e.
in front of rad = blow.
behind rad = suck

Just a thought

Edited by RallyRed, 16 February 2020 - 06:51 PM.


#16 76lxhatch

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Posted 17 February 2020 - 05:20 AM

If your fans are set to turn off below thermostat temp then they will stay running - the thermostat's job is to keep the engine above that temperature. Normally the off temp would be at least 5 degrees hotter than the thermostat, a quick search suggests that the factory EFI settings are significantly hotter (for comparison):

https://www.pistonhe...0&f=69&t=560298

 

The above also suggests that none of your temp numbers are excessively hot for an LS, they are designed to run warmer than older engines. Pressure and coolant additives significantly increase the boiling point, provided the coolant is still liquid it does its job.






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