Cranking the engine before starting?

[CharlieJ]

Hi everyone,

Realizing that I can crank the engine without starting it while holding the accelerator to the floor when turning the key, I wondered if this can be beneficial for a cold dry start. I think this would prelube the bearings before actually starting the engine. What does everyone else think? Can this beneficial? Or, is it a waste of energy?

 

[oilboy123]

Probably not enough difference to be worth more wear on the starter etc. Unless you are getting a dry start I would not do it.

If you did have a start up rattle I would check that your filter did not have a ADBV that's bad.

 

[Colt45ws]

Would not be worth the wear and tear on the starter and battery.

 

[Shannow]

Depends on what stops the car from starting with a floored accelerator.

Probably cuts fuel and spark, so wouldn't hurt anything other than the battery and starter.

There's still quite a load on the pistons due to compression anyway, and the cams/lifters don't even know they are on an engine anyway, so I don't see it saving/helping much.

 

[labman]

Good point. I have replaced a good many starters and batteries, but the only bearings were in an English car.

 

[demarpaint]

The only benefit I would see is for a car that sat for a long period of time. For the daily driver, or even a car that is used lets say every two weeks I don't see much benefit.

If you have a car that sits for several weeks at a time get a pre-luber, if you are really concerned.

 

[Fordiesel69]

On my crown vic's and lincoln's I cannot prefill the oil filter after I change it, so yes I hold the pedal down to the floor and crank till I get an oil pressure reading. Otherwise there is some rattle I don't like.

Other than that, it is a waste to do it any other time as the drainback valve keeps your oil in the system.

 

[KrisZ]

I feel the same here, the extra wear on the starter and batteries is not worth it at all.

Canadian climate is as harsh as it comes, yet there are tons of cars on the road with 300k KM or more, I see many people either idling their cars for 30min in winter or just starting and driving off not even taking it easy until the car worms up.

The "most wear occurs on start up" is blown way out of proportion by oil companies and it is true, but so what if the car still lasts 300k or more with regular oil changes and keeping proper oil level.

 

[demarpaint]

Originally Posted By: Fordiesel69
On my crown vic's and lincoln's I cannot prefill the oil filter after I change it, so yes I hold the pedal down to the floor and crank till I get an oil pressure reading. Otherwise there is some rattle I don't like.

Other than that, it is a waste to do it any other time as the drainback valve keeps your oil in the system.


In your situation I see no harm since it is not a daily event. If anything what you're doing would be beneficial.

 

[TallPaul]

All the manufacturer has to do is go to an electic oil pump set up so you could do a pre-pressurization before starting the engine. There are devices you can bolt onto your engine that hold pressurized oil that you can release at start up to goose the system. The canister fills with pressurized oil during normal engine operation and then releases with some trigger (presumably at your control). They have been talked about on this site before, probably several years ago. You should be able to find them at racing equipment suppliers.

 

[bigbird_1]

Originally Posted By: TallPaul
All the manufacturer has to do is go to an electic oil pump set up so you could do a pre-pressurization before starting the engine. There are devices you can bolt onto your engine that hold pressurized oil that you can release at start up to goose the system. The canister fills with pressurized oil during normal engine operation and then releases with some trigger (presumably at your control). They have been talked about on this site before, probably several years ago. You should be able to find them at racing equipment suppliers.


Anyone installing something like that on a non-race engine is suffering from OCD.

 

[Eddie]

Probably do more harm than good to the cylinders, rings, starter & battery. At cranking speed the crank is not turning fast enough to through oil to the piston area so you are extending the dry start as far as piston, rings and cylinder are concerned.

 

[Chris142]

Most oil pumps wont pump oil at cranking speeds. So your just cranking a dry engine over and over.

 

[demarpaint]

Originally Posted By: bigbird_1
Originally Posted By: TallPaul
All the manufacturer has to do is go to an electic oil pump set up so you could do a pre-pressurization before starting the engine. There are devices you can bolt onto your engine that hold pressurized oil that you can release at start up to goose the system. The canister fills with pressurized oil during normal engine operation and then releases with some trigger (presumably at your control). They have been talked about on this site before, probably several years ago. You should be able to find them at racing equipment suppliers.


Anyone installing something like that on a non-race engine is suffering from OCD.


Call me OCD then. I have a Pre-Luber I Installed in a Ford Van back in the late 1980's early 90's. Mine is an electric oil pump mounted on the left fender well. It pumps oil through the engine simply by flipping a toggle switch. Oil is pumped from a special plug which is where the drain plug on the oil pan is. It goes through a small filter and goes into the engine where the oil sending unit is via a "T" fitting. The reason I installed it is 1. Because this van sat for sometimes months at a time without being started. And 2. Because I suffer from OCD.

 

[XS650]

Originally Posted By: bigbird_1
Originally Posted By: TallPaul
All the manufacturer has to do is go to an electic oil pump set up so you could do a pre-pressurization before starting the engine. There are devices you can bolt onto your engine that hold pressurized oil that you can release at start up to goose the system. The canister fills with pressurized oil during normal engine operation and then releases with some trigger (presumably at your control). They have been talked about on this site before, probably several years ago. You should be able to find them at racing equipment suppliers.


Anyone installing something like that on a non-race engine is suffering from OCD.


It's what you call a solution in search of a problem.

 

[Craig in Canada]

I have only done anything like this with the PLUGS REMOVED prior to taking a stored vehicle out of storage. With the plugs removed there's very little bearing or starter load.

On the street I would never bother. Why are you making the assumption that the bearings are dry?

 

[440Magnum]

That's actually a lot WORSE for an engine with a flat-tappet cam than firing it right up. When the cam is rotating very slowly against the lifters, the oil film gets broken and "pushed aside." When the speed is higher, the hydrodynamic wedge of oil stays intact. That's why you're never supposed to let an engine drop below 1500 RPM while the cam is breaking in, and you're not supposed to set your idle speed too low either. If you turn the engine for a long time with the starter, you're just slowly grinding parts together.

Now with roller cams its less of an issue, but I imagine that the same phenomenon occurs, maybe to a lesser degree, with the rollers and with the crankshaft bearings.

 

[TallPaul]

Just open up the engine every time it has sat for too long and slather assembly lube over the critical parts.

Now that goes waaaaay beyond OCD!

 

[mechtech2]

Start the car normally.
Cranking and not starting does not build pressure like a running engine. Not nearly the same.

 

[Ken2]

Plenty of oil sticks to the engine parts for many, many days. Who has bearing failures just from starting? I've never heard of one.