Engin's running too cold?

[dom14]

Hey Guys,

My RB30(Carby dual fuel) was kinda running bit too 'cold" yesterday, if I'm correct about that.
I was driving for about couple of hours in the evening and the temperature gauge doesn't seem to be
going as high as it usually did.
It's a fairly cold evening last night, for around 4-5 degrees in Melbourne, but
I've never seen the temperature gauge dial going this low even in colder days, after driving for that long.
I was running the heater on and off, but I do that in winter anyway.
I did "fiddle" with AFR mixture screw on the carby to get the petrol to run previous days back, but it wasn't
running on petrol yesterday and won't be for a while. So, it was on LPG.
It didn't make much difference whether I was stationary on idling or doing 80km/h on the highway.

I didn't think carby AFR setting mattered that much for LPG anyway, or does it?
LPG mixer has it's on AFR setting which I've never touched.

So, I didn't think the engine's running bit cold due to running too rich, or is it possible with my "fiddling"
with carby AFR screw??!!

When I started and warmed up before I took off yesterday for the drive, the engine was purring initially,
but didn't sound like as much purring on the highway. Kinda sounded bit rough, while I was keeping any eye on the seemingly low
temperature reading on the temp gauge.

So, I'm guessing,
1)Running too cold/too rich possibly due to my carby "fiddling" with the mixture screw? or
2)Coolant thermostat is in early stages of dying?

I took the picture while idling after I got home yesterday.
It idles around 950-1000rpm on LPG atm. I don't seem to be able to get it down to 850ish, warm or cold on LPG
Any advice please guys?

Thanx

[billyj]

thermostat is morethan likely sticking open a bit and letting the coolant flow too much at low temps

[Throbbinhood]

Cold weather does weird things to these carby motors mate!

[4bye4]

Cold weather does weird things to these carby motors mate!

I would agree Dom. From what I have been reading about your weather over there, I would just let it go untill you have a big thaw and see if the temps come back to normal. And BTW, your correct in the GAS AFR is set in the regulator.
Cheers Tony

[threedogs]

Was the heater temp hot when in the hot position or luke warm.
Just saying as mine takes ages to get to temp lol

[macca]

Remember trucks used to have a blind in front of the radiator grill to maintain temperature.

It's been cold here and worse down your way according to my sister in law, so could be down to ambient being so low.

[dom14]

Cold weather does weird things to these carby motors mate!

Absolutely mate. Especially, these old beat up carbies can't handle sudden cold weather fluctuations.

[dom14]

Was the heater temp hot when in the hot position or luke warm.
Just saying as mine takes ages to get to temp lol

Nah, it's kinda annoying, 'cos when I turn the heater all the way up, then it was getting too warm inside the car.
I was bit too brain fogged to realize that I could've simple play with the temp control slider to keep the desired temperature inside the car.

[dom14]

thermostat is morethan likely sticking open a bit and letting the coolant flow too much at low temps

Yeah, just to be safe, I reckon I should pull it out soon and test it outside the car with boiling water.

[JME_GU]

Regardless of outside temperature, the thermostat should not open until the engine is up to temperature. Exactly the same thing happened to my TB45, the first thing I noticed was that on long downhill runs the engine would get slightly colder, changed the thermostat and all good.