Do ya crank it - or do ya start it?

[silverian535]

Guys, my pride and joy sits in the garage for a couple of weeks at a time and then has a blast.

The question is: Do you crank your engine over before starting, to get the oil going around - or do you just start her up?

Which is better for the engine (anchor) ?

Ian

[Steve_D]

Neither is terribly good for it, having stood for a time.
Think about fitting an Accusump.
This is a reservoir of oil which is maintained at pressure and will protect the engine from oil surge and loss of pressure when throwing the car into corners. This would be most relevant on trackdays.
However it is not so commonly known that when you put your PJ to bed and switch of the ignition a valve closes trapping the oil in the Accusump.
In two weeks time turn on the ignition (opening the valve) and wait a few seconds before starting the engine. In this time the oil will release and fill the oilways and bearings before the engine moves.

Steve

[pearl nicholas]

mine sits around for months at a time,i usually just start it and the oil pressure comes up after a second or two,i dont think cranking it does it much good

[Comadis]

if you want to do something good to your engine, unplug the main ingintion lead (that the engine wont fired up), crank it with the starter until the oilpressure builts up. reconnect the lead and start it.

[silverian535]

It is relatively easy to crank mine over before starting as I have twin 45s with no choke connected.

If I just turn it over it will not start and pressure comes up after a few seconds. I have to pump the throttle 3 or 4 times to start, then away we go.

Ian

[h8wyn]

The most damage occurs to bearing surfaces at higher speeds and loads. When the engine is running all the crank bearings have to absorb the 'punch' of the detonation in the piston and convert this to rotating energy. The other factors affecting oil are temperature and pressure. Avoid either method if its particularly cold, say around 0 degrees C or less as the oil will be very viscous (thick and gooey) and will not flow freely. All oil pumps are designed to pump oil even at engine cranking speeds, albeit at lower pressure, but this will get oil to the essential parts.

If you are really concerned, and taking all of the above into account I recommend the following:
Warm up the engine block with fan heaters etc in your garage. Disconnect the HT leads to all spark plugs. Crank the engine for around 5 seconds, leave for a few minutes, then crank again for around 10 seconds. Finally connect the HT leads and fire up. Avoid revving the engine until it starts to warm through, the least damage you can do is at idling speed.
Good Luck - I'm sure you will be fine.

PS. If you have bike engine, do not disconnect the HT coils that sit on top of the spark plug holder, pull the complete spark plug holder off the actual spark plug but leaving it connected electrically. This will avoid damage to the ignition system from operating it in open circuit mode.

Wyn. Chartered Engineer.

[GreenV8S]

h8wyn said:

the least damage you can do is at idling speed.

However, loads on the valve train go up as the revs drops around idle and some engines will suffer from accelerated cam/follower wear under those conditions. Moderate revs (say 2000 rpm rather than 1000) are likely to be preferable from this point of view on most engines, but still low enough that bearing loads are not an issue.

[eccles]

if i ever left my Jem for any length of time i'd whip the plugs out, then crank the engine over with no load on anything, and once the oil pressure was up, plugs back in, leads on and off to go.