turning over an idle engine

[wwheeler]

I am wanting to know if I should turn the engine over while my car sits idle.

I am doing a large project which includes rebuilding the rear axle. The car has been sitting for four months now and will probably be another three months before the project is done.

The gas tank and pump are off as well as pretty much everything behind the transmission. The engine is complete and full of oil and coolant and the trans has fluid. I am concerned about the engine internals going dry and thinking that turning the engine over a few times once a month may keep everything oiled.

I would disconnect the coil wire and the gas is already drained. Any other complications? What do you guys think?

Thanks!

[enochbell]

The only worry to me is the IP.  The pistons are lubricated by gasoline, and if the gas is dry you might run dry in the pump.  Probably not a big deal for a few revolutions every couple of weeks, but I would not want to go more than 4-5 cycles (2-3 months).  Just my $.02
g

[mdsalemi]

Wallace,

Being in Texas, you probably don't encounter the same weather we do here in the upper midwest.  Every autumn, sometime late October/Early November depending on my schedule, and a predicted "dry" day, and the overall weather pattern I store my car.  I pick it up no earlier than Easter weekend, sometimes later; this year it was Memorial Day.  Thus the car sits for anywhere from 5-7 months.  It has been doing this exact same thing since 2001.  I have suffered no ill storage effects.  If I am up at the storage in the winter, and the roads are dry, I take it out for a spin.  If roads are snow covered or wet, I leave it alone.  The only thing I do is clean it before storage, and add Sta-Bil to the fuel tank which is full and topped off.  I run a few miles to ensure the Sta-Bil is throughout the system.

Somebody told me this weekend they prefer Sea Foam. http://www.seafoamsales.com/tech-info-gas-engines/  Sta-Bil has appeared to work well, and is an industry standard. http://www.goldeagle.com/brands/stabil/default.aspx  Note they also make a marine version with enhanced properties.

Personally--my opinion only--your "down time" on the car should not pose an issue.

[wwheeler]

Thanks for the replies. I hadn't thought about the IP pistons and that could be a problem. It is nice to know that storing for 6 months shouldn't cause a problem. That is reassuring.

I have never stored a car in my life, so I am ignorant to that. North Texas is usually car driving weather 10-11 months out of the year. Some days can be great even during those two months. I do use Stabil but don't have a gas tank now. Once I do fire it up, I will change the oil and check the coolant ph beforehand as a precaution. With a 100+ temperatures now, I shouldn't have to worry about condensation being a problem until November.

I will sleep easier now thank you.

[Benz Dr.]

The only worry to me is the IP.  The pistons are lubricated by gasoline, and if the gas is dry you might run dry in the pump.  Probably not a big deal for a few revolutions every couple of weeks, but I would not want to go more than 4-5 cycles (2-3 months).  Just my $.02
g

 The pistons in the IP are lubricated by engne oil, not gasoline. Running on only gas, it might last a couple miles if you were going slowly. The damage would be exstensive.
 
There would be no problem spinning the engine over but I`m sure it`s not needed.

[ejboyd5]

Leave it alone.

[enochbell]

Dan,

Thanks for the correction.  I was told by the guy who adjusted my pump many years ago that the bottom end of the IP was lubricated by oil but that the top end had tolerances so small as to make oil lubrication impossible.  That is incorrect?

Thanks,
g

[280SE Guy]

Wallace,

A few squirts of Marvel Mystery Oil in each cylinder would help keep the rings free (at least the top ring).

Regards,

Bob

[stickandrudderman]

I recently fired up an engine that hadn't turned in over a decade, although the car had been stored in a dry underground garage.
I drained the oil, installed fresh oil, pulled the king lead and cranked for oil pressure, re-installed the king lead and fired her up. She purred. Even had half a tank of fuel which didn't cause any problems in the subsequent 50 or so miles I did in her.
It was a 110 engine but the point remains the same.

[ja17]

Hello "g"

Your mechanic was mostly correct, the clearances of the pistons in the pump cylinders is in millions of an inch. The oil line coming from the block to the IP, supplies oil to the the pump cylinders under pressure. A tiny horizontal groove in the IP cylinder walls, fills with oil and  seals the piston.
 This "oil ring" seals like piston rings do on a real engine.

[enochbell]

Joe,

Thanks, I appreciate the explanation.  I think these mechanical pumps are absolutely amazing and probably the most unique mechanical feature of the cars of this era.  And there are probably not more than a dozen people who truly know their intricacies. 

Best,
Greg

[ja17]

Yes Greg,

These are a marvel of German Engineering. Here is a pic of the IP piston and cylinder out of the pump. You can see the tiny oil groove in the bore ............

[glenn]

Gotta pix of the helical groove on the piston?

[ja17]

OK Glenn,

Here is a pic of the "helical groove".

The rack rotates the plunger piston which rotates the helical groove and changes the amount of fuel allowed to enter the cylinder of the IP. The fuel release groove ends the fuel delivery precisely as the fuel under pressure, suddenly escapes through the hole in the top of the plunger piston to the release groove as it passes the fuel opening in the cylinder.

[glenn]

Joe, Thanx  Wanted to get the pix out for the folks to see just how the injector pump works.  Worked on the ME 109Es???   Upside down........