Originally Posted by JackMosby
27deg here so I went out to try my luck.
Made about two cranks and fired right up and hunted on the governor for about 5 seconds before settling in at about 5k rpm’s.
My son and his wife sighed a big relief, as i think we have about overstayed our welcome
I think you mean 500rpms which is about where it should be set to idle. Crown 6-71's typically idle about 600 to 650 or so. So anywhere from 500 to 650 is normal. The governor hunting is perfectly normal too until it settles and gets warmed up a little. All part of the many charms of Detroits and why we love them so much. The normal start is of course to have it running in a revolution or so and almost before you get your hand off the key. Cold starts may have it crank for 1 to 3 seconds but they usually catch and then you're OK.
Also as you drive that Allison transmission, remember to always mash the throttle to the floor HARD as you accelerate. You always must drive the Detroits like you're mad at them and always keep the rpms up as high as you can. Don't baby it just because it has an automatic. Unspoken here is to watch the transmission on downshifts as you go up grades and if it keeps it in a gear without downshifting at around 1500 rpm, you need to manually take over and place it in the next lower gear. That's how you prevent lugging and overheating the engine.
Also remember to use the proper oil or you WILL have problems. I've put up many threads about the oil but you can contact me direct if you want and I'll give you the low down.
I almost didn't find this thread because you didn't use Crown anywhere in the title. As you obviously found out the naturally aspirated Detroits with their slightly higher compression ratio's will start pretty good at pretty low temps. I would suggest you go buy a can of starting fluid (ether) and keep it on hand for a really cold day, down around 0F, where things could get a lot harder for it to catch and get started. Be sparing with the ether and many say it's hard on the engine since it washes the oil off the cylinder walls but in the cold where it's needed that's a minor thing to worry about.
A Crown with a naturally aspirated 6-71 in good condition will start reliably down to almost 0F but may need a little starting fluid help that low, but temps in the 10-20 range will not be too bad and may only need a little more cranking to get it hot in the cylinders to fire the fuel. While it's still cold and barely burning the fuel it will pour out white smoke which is the un-burned fuel and as it warms up slightly in the cylinders the white will go away and then things will smooth out a lot.
It's a bigger problem to have the fuel start to gel and not flow well, therefore the recommendation to add a fuel conditioner to prevent gelling is a very good idea. Some States add this when they winterized the fuel but Texas probably isn't one of them since it's so rare. Fuel gelling in the fuel lines is a problem while cold soaked but as the engine warms up, and it starts driving, the hot fuel is constantly being recirculated back to the tank which starts to get pretty warm to the touch. This is designed-in to cool the injectors while at the same time keeping the fuel pre-warmed and preventing fuel line gelling at low temps.
Don't ever expect the engine to get hot enough to produce heat for the heater inside by just idling. That won't happen until you start driving it on the road and even then it will take more than 15-30 minutes to generate enough heat to open the first thermostat to let the coolant into the heater loop. It has two thermostats and it's an extremely well designed system where the engine heat is available to the interior heaters first, then the second thermostat starts to open and rejects the excess heat to the radiator when it gets that hot. But the big thing is to know that the engine will NOT generate any excess heat for even the heaters until you start to actually drive it. It's part of why diesels are used, they are extremely efficient in how they use fuel and no fuel is wasted in unproductive waste heat like in a gas engine.
Quite by coincidence I've been training a new Crown owner over the past weekend and they are also driving into the teeth of this Polar Vortex and I sure hope they are OK and make it through to the East Coast where they live. Their Crown is just like yours with a Naturally aspirated 6-71 and a ten speed road ranger manual transmission, so they have a real challenge on their hands, my fingers are crossed for them. They plan on the Southern Route I-10 through New Orleans and points East from there, so, as unexpected as it might be, keep an eye out for their all yellow Crown, while on your trip, they can't be too far away, and they're passing through at about the same time as you.
Two Crowns heading for a new life in the East. Too cool, saving them from a fate worse than death here in Kalifornia.
I'm interested in where and who you got that Crown from. It looks familiar to me somehow but I just can't put my finger on where I've seen it around. Please email me direct and then we can call/text after making contact. I'll also be just a phone call or text away if you have any questions. Happy Trails. firstname.lastname@example.org
See! The, "Crown Crown Crown" does work...... but it helps to have the Crown in the title at least.