Using engines after a few weeks of non-use

MidlandsOnSea

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There was a recent post which mentioned a problem with oil retreating to the sump after engines have not been used, thereby creating a problem with wear when the engines are next started. With a diesel, what period of inactivity would allow this to happen? What sensible steps can one take to prevent the damage? Our boat can get left for 4 to 6 weeks at this time of year, and the prospect of taking injectors out to lubricate the cyliners before use is not very appealing.
 
Most of it is bunkum and nonsense. A good motor with clean oil is OK for ages. What you don't do is start the motor and then rev it up. Crank it at no throttle and then as it fires, bring it up gently. To put this into context, what do think happens when a new motor is sold and installed (into any installation) especially as some are over a year old when first used??
 
not easy to prevent engine start on modern engines but leave the throttle shut and crank over till you see movement on the oil pressure gauge, then start at minimum revs, do not gun until temprature rises, best to trickle away from berth as they warm quiker when under load.
 
If you're really bothered crank it over with the fuel cutoff / stop button pressed for 10 seconds, then release.

Otherwise start up as indicated in other posts.

Modern lubes retain a thin film for years and coupled with the fact that cast iron cylinder bores and main bearings actually absorb small quantities of lubricant, means that leaving an engine for an extended period is not an issue.

I opened up an old LR engine after several years of non use and was amazed to fing all the moving parts still had a thin film of oil on them - and that was in the days of 20/50 multigrade.
 
Don't you just love scaremongering! As others have said no it won't cause any probs. The oil pump will have pumped sufficient oil around the engine before you've even thought about it! No different to leaving your car for a couple of weeks while you go on yer hols.
 
My engine stalls unless I give it a good rev. Does that explain why I have oil in the bilge?
 
Agree entirely. An engine will develop oil pressure within a second or so of starting, unless it is very worn indeed. But it is important to ensure the pressure has built up (warning light out, or gauge responding, before revving up.

If the correct grade of oil has been used, there will be sufficient oil residue to provide prtoection at low revs for the first few seconds after the engine 'catches'. Oils and engines are designed to cope with this. It is only the old clunker with badly worn main bearings where there is an appreciable delay before oil pressure builds up, and if the engine is as bad as that, there is nothing much left to protect anyway!

Turbo charged engines do need around 5 seconds before they are revved, to ensure the turbo is fully lubricated, and conversely, a charged engine should never be shut down until it has idled for at least 10 seconds, to allow the turbo to slow down before the oil pressure is cut off.

And HLB: you never SHOULD have oil in the bilges! Environmentally very bad, and liable to incur Harbour/Marina Masters wrath if discovered (with hefty fines for bad cases!) Engines MUST be fitted with a drip tray to catch any spillage or drips.
 
Its a Ford so what do you expect!!.....that and the dodgy bloke that you had put it in!

Seriously it shouldn't. Not an oil burner. What make injection pump have you on your one?
 
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