[bangn]

when it comes to idle quality, im on the pursuit for perfection. SJ70 1300

I got an exchange carby this week by a reputable source so I know its mickey mouse.

My cooling system is A1, new genuine thermostat, new coolant, new water pump, new hoses, radiator is spot on for flow.

I Find that the old 1300 doesn't seem to hit the temp gauge smack on in the middle, it always sits below half on the road.
If you sat the car in the driveway and let the cooling system cycle the idle speed would be spot on.
but driving around the idle speed can be sitting a bit higher than it should.. about 1200-1300 as it gets cooler (being winter temps). But after sitting at the lights for a while it starts dropping.

pretty norm?

[alien]

Normal for a sierra temp gauge is around the bottom 1/3rd or there abouts... If mine reads half way on the gauge that's about where my viscous fan kicks in full pelt... the difference between 1/3rd and half way on my gauge is about 5 degrees C (measured at the thermostat housing with an IR gun).

In short - don't trust your temp gauge. As long as it sits in the same spot all the time you're PROBABLY ok...

As a reference, do you trust your fuel gauge? I don't think i've ever seen a sierra with an accurate one.

[Marko_SJ]

Alien, I think he's talking about idle speed varying with engine temp.

I deleted my auto choke and generally the engine runs slightly faster when it is warmer. Cold start two pumps of pedal to get some fuel in there, it'll idle around 800 RPM, as it warms up about 1000.

[droverdave]

My temp gauge and fuel gauge both work fine.

The temp gauge on my car sits just under horizontal in normal traffic, and on the highway usually sits at maybe somewhere between 1/3 and 1/2. (brand new everything to do with coolant)

Only on uber soft sand and full of stuff have i seen it above horizontal (and when my car was overheating due to head gasket). I have had a radiator hose pop off, and have seen the temp gauge rise steadily and then fall rapidly once all the water runs out. So i trust my gauge.

OP sounds like your car is running fine.

On the standard carby there is a dashpot that stops the throttle from slamming shut. So basically when you let off it shuts to like ~95%, then it slowly closes the rest of the way (over say 5seconds). Perhaps this is what you are experiencing. mine does it too, it can be idling a bit high, sometimes if you blip the throttle you can get it to idle lower, i suspect the dashpot on mine gets a bit stuck sometimes too.

[bangn]

yeh sits where you say alien. The thermostat cycles as it should so must just be the gauge. But sounds like its the norm for this choke system from what you guys are saying.