idling extended period of time

[Mitch//pa]

my A's are not always driven but i still like to start them up periodically and let them idle 30 minutes or so especially in the winter when there not driven at all. do you guys recommend letting them idle at the base idle setting which is low or should i adjust the throttle lever at the collumn to raise it a few more hundred rpm's. the reason why i ask is to keep the battery charged up and by raising the idle it charges the battery with a little more voltage. i do run tom's evr in one and the other is stock with the 3rd brush and both have the diode cutouts.

[Aerocraft]

It is my suggestion to not run them at all in that manner during long term storage. If you are concerned about corrosion, I suggest that you remove the plugs, "fog" the cylinders with oil, and replace the plugs. A battery tender does very well at keeping the battery fully charged. Why not plan to take each car out on a regular basis when you can run it at normal speeds for at least a half hour.

I am sure you will get a response from an oil expert who will explain what those idle runs are doing to the oil.

[Bill Steiner]

Hi, I would speed it up a little. You get more splash lube that way. This is just My opinion. Bill

[Chris in CT]

Hi Mitch, Both Bill and Aerocraft are correct. Best thing to do is to set the engines up for storage. However, if you want the cars "ready to run", you need to speed up the idle so that you will not get the characteristic carbon buildup in the combustion chamber, and you need to run them long enough to get them to full operating
temperature. Think 15 minutes or so...

[Mitch//pa]

i dont want to set them up for full storage as i want to jump in them anytime i want and the best bet is to idle it up a little. what did they do back in the day if the vehicle was idling extended periods did it put an extra drain on the battery? my main concern was the charging of the generator output at very low idle. i am aware of the carbon and oil splash etc.

[Kurt in NJ]

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I also like my car to be ready for that nice day in the winter, in the 40 years I have owned the car it has never been setup for storage.
I expect it to start wether it has been 3 days,3 weeks, or 3 months.

The practice of starting and letting it idle causes damage to the engine and exhaust by causing condensation, which combined with the products of incomplete combustion cause acid , if an engine is started it should be run until the oil is hot enough to boil off the contanimation ---even more important if you use non-detergent oil.

If you are worried about the battery put a trickle charger on it once a month for 24 hours.

My method of acheiving long battery life has been --do nothing, this method has given me battery life of 7-9 years for regular batterys, and so far 13 years for the Optima.

As for idling for extended periods --I liken it to a parade, here on the 4th we have a long parade, about 1 hour, I use the horn many times (so much that the horn button gets hot), the parade speed is idle, 1st gear, I do fine speed adjustment with spark advance, there is no + charge during the whole parade, --no problems if the battery is good, the same as if you loose the charging system, you still can drive several hours.

If you have a diode cutout and the battery voltage becomes lower than the voltage the gen is making (at idle) it will charge--some.

[J Franklin]

I would think rather than just running the engine in place you should take the car out for a half hour drive. You will then be oiling the driveline and chassis parts by moving. You will also achieve higher temperatures in the engine helping to burn up condensate.

[Bob A.]

Kurt,
"If you have a diode cutout and the battery voltage becomes lower than the voltage the gen is making (at idle) it will charge--some."
I believe A diode is a one way valve (check valve) for electric, which is used in place of a cutout relay. It has nothing to do with charging ,only to connect and disconnect the generator from the battery.
A lot of us like to play with these cars, So starting them up in the winter won't hurt as long as you run them up past idle and also until you burn out the condensation. I would advance the timing slightly off the retarded position while doing so. I think letting them sit around all winter is worse. The oil runs off the cylinder walls and everything else that gravity has an affect on . There will be plenty of time in the good months to blow out any carbon. This is my opinion. Please don't mind my spelling or English, I didn't pay attention in school.

[Mike Mc]

As the others have mentioned you need to be careful of condensate build up in the oil, but also in the exhaust. If you've no choice, I'd go for a fast idle for at least half an hour.

A few years ago, I took an old car out for a long drive after a year of occasionaly idling the motor. The oil level on the dip stick dropped quite noticibly, then stopped moving, which I attributed to a build up of moisture in the oil boiling off. It was a very quick oil change after I got home!

[Kurt in NJ]

Bob, Yes, the diode is like a one way valve, whenever the generator voltage is higher than the battery voltage (or the voltage the other side if the diode) there will be flow --in this case "some" charging of the battery.

I have taken engines that have sat for years apart to find that there is still oil on the bearings, and the piston skirts , because the parts fit close oil stays there , capillary action keeps it there.

To boil off the condensate from the oil it will take longer than 1/2 hour from startup,the oil has to be at a warm enough temp ---actually all of the engine needs to be at a temp to burn off condensate or it just moves to a cooler place.

[Tom Wesenberg]

The best way to treat your engine would be to fog it with oil, cap the intake and exhaust, and don't touch it until the salt is off the roads, when you start driving it again for the season. I haven't been fogging mine, but I don't touch it for the 5 or 6 months of winter, and it fires right up in the spring. I always change oil just before parking it for the long winter.

[Tom Wesenberg]

Originally Posted by Kurt in NJ

Bob, Yes, the diode is like a one way valve, whenever the generator voltage is higher than the battery voltage (or the voltage the other side if the diode) there will be flow --in this case "some" charging of the battery.

I have taken engines that have sat for years apart to find that there is still oil on the bearings, and the piston skirts , because the parts fit close oil stays there , capillary action keeps it there.

To boil off the condensate from the oil it will take longer than 1/2 hour from startup,the oil has to be at a warm enough temp ---actually all of the engine needs to be at a temp to burn off condensate or it just moves to a cooler place.

Kurt brings up a good point. In the early 80's I bought a 1929 Chevy that had been cut down into a tractor with a Model TT worm drive rear end. When I went to pick it up I noticed that it had a white coating all over it. I asked the guy if it sat next to a cement plant and got a coating of cement dust. He said "no, the pond had risen and it sat underwater for several months". I was affraid I just got took, but all I really wanted was the head. When I pulled the drain plug about 5 gallons of water came out. When I pulled the oil pan the engine looked like new inside. The cam lobes didn't even have rust, but still had a coating of the old oil on them. When I pulled the head I discovered someone had bored it .020" over and put the standard pistons back in.

[Aerocraft]

It has been suggested to me by a good friend who was an petroleum engineer and expert from Standard Oil of California that, in order to burn off the unwanted "stuff" in the sump the engine needs to be run at a minimum of 165 degrees oil tempeature for a minimum of one half hour. Whether or not these numbers are accurate, it should highlight the need for frequent oil changes since it is at times difficult to get a Model A engine up to 165 degrees water temperature. One of my buddies drove his Coupe, with a water temp guage installed, over thirty miles last fall (cool day) at 45-50 mph without being able to show that temperature.

[Bob A.]

Well I guess I'm never to old to learn something.

[Bob A.]

Then one must ask : Why do engines seize when lying around?

[Barry B./ Ma.]

Well, I'm like Mitch and I want to be able to jump in the A in the winter and run it so once a month i'll fire it up and move it into the yard. If the roads are dry I'll take it for a little ride. I change the oil and antifreeze in the spring.

[Bob A.]

Hey Barry, I'm out there all year too. I don't run it in the snow or salt laden roads also not in the rain but I did get caught a few times. I was so happy this year because I got around to hooking up the heater.Before the heater, it was colder in the car than outside.

[Tom Wesenberg]

Originally Posted by Bob A.

Then one must ask : Why do engines seize when lying around?

Sometimes insects or rodents get through an open valve and mess it up. Other times cool moist night air can get in through an open valve or carb and form rust.

I bought a 1950 Studebaker with a stuck engine. The owner said he put aviation oil in to try to free it, but couldn't make it budge. After I bought it I also put oil in the cylinders and evern try bumping it using a 12 volt battery, but no luck. When I removed the head it looked like a perfect engine inside except for a very light touch of rust on just a small part of the one cylinder with the open exhaust valve. I had a hard time believing that would stick the engine as hard as it did.