No wet sump crank turns through the pan of oil for its lubrication - for the very reasons you site! But that type of system is still referred to as a wet sump system!!! It's just simply an "I.D." term.

In any case, I'm not arguing about what the crank is actually experiencing in normal wet sump systems, etc.

To reiterate, I'm simply saying that:-

"wet sump" - pan of oil attached to underside of block below crank + engine-driven pump
"dry sump" - oil reservoir/pump outboard/independent of the engine.

If you mention "wet sump" and "dry sump" terms to an engineer, the above is what he'll expect you're on about.

 

Pdang, do you know ANYTHING about engines whether it be car or bike?

There is so much wrong with almost everything you've said it's hard to take you seriously.

I know of many factory wet sump bikes I'd love for you to show me a single dry sump one!!

 

Yes, you did. The problem is that your definition of "dry sump" is one unique to you. Ditto your definition of wet sumping. It's because you don't "get" the terminology that you're tying yourself up in knots.

You seem to think that wet sump = the crank splashing in oil and dry sump doesn't. That's completely wrong, as you've been told directly and as DJ's external links have already demonstrated.

That's complete rubbish bloke. You might find very large low speed marine diesels using some element of splash lubrication, but car and bike engines moved away from it many decades ago.

However, car engines are still classed as wet sump systems, because, as I explained to you in post whatever it was, and as others have now concurred, a "wet sump" is literally just that - the oil drains back into the sump and therefore it is regarded as "wet".

The reasons motorbikes often (but don't always) use a scavenge (i.e. dry sump) system is partly because of gravitational forces and leaning the bike, and secondly because of the increased ground clearance you can gain from deleting a conventional sump pan.

Sure, consider yourself corrected. Of course they're wet sumps but none of the above will have produced a car engine with your definition of a wet sump (i.e. the crank within the bath of oil) for decades. Bikes and trucks I couldn't comment on.

Given current form, it seems pretty clear that it's yourself who got you banned. Either learn from whatever happened to you before or repeat it - the rest of us will carry on as we were, one way or the other.

 

I'm not normally one to pile on, but:

Funny that, but not a single mention of cranks in that entire paragraph

 

S'alright, this thread gained an extra one tonight.

 

This thread owes me an hour & a half
Great info from the ones that know what there talking about IMO (Splitpin, David)

 

It's a good night's "entertainment" though, innit?

 

True learnt somethings aswell which is nice.....and some of the, erm, shall we say less informed posts made for interesting if not slightly aggressive reading

 

No need for any apologies, all part of the system.
I think most of us are able to sort the wheat from the chaff.
I am still a little confused as to whether or not I need an uprated fuel pump though. Mine is a WRX not an STI.
Oh, and in answer to the question "show me a modern bike that has a wet sump system" My 955i Triumph does. See quote below from the workshop manual.

Lubrication System: Wet sump, 3.4-qt. cap.

 

almost all bikes have a wet sump. there are very few that have dry sump aprilia and buell have one or two, and one or two bmw's have a hybrid design.

 

No you don't need one mate, It was only part of the Sti PPP.

Aaron

 

It wouldn't do any harm, especially in very cold weather.
If you are keeping the car for a year and are not bothered it probably won't make any difference.

 

Splitpin : You have been deceiving me. I thought these were wet sump engines. Jesus, I have been wrong all these years and need to re-evaluate my thinking. I better tell Matt at Roger Clark's too because he has developed a dry sump system over the Winter for these engines and I seem to think Zen developed one too. How were we able to go on for years in this deluded fashion? Just shows you we don't know as much as we thought.

Off Topic. Can we make this thread go to 20 pages..........................................jus t for a laugh.
Whoever would have thought that? These engines have been dry sump all the time.



I like this bit :

Splitpin : Do you mind if I retain this in my drafts folder so I can add it to future posts, emails or letters particularly when dealing with beurocracy or experts? I will of course add copyright Splitpin if that is OK with you?

 

I wish people would stop posting in this thread.

This is getting riddiculous!!!

 

If Morfo has posted that, fine, but you have the option not to come on here, unless of course you are hooked but we do have to keep it semi- sensible or we will end up in the muppets

 

Sssshhhhhh, don't flipping tell everyone!

Nooo, don't tell them! If RCMS are going to waste their time developing a dry sump system they never needed in the first place, that's just going to limit the amount of time they have left to make their car, like, faster, innit?!

Consider it a gift!

The irony is that Morfo was happy by post #22, as, as he said at the time, he was operating on the "If in doubt, ask" principle. He asked some good questions, got some good answers, and clearly learnt from the process. Everything that's happened since is just... the process of evolution.

 

While on the topic of oil changes and only slightly off topic this may be of interest to some of you.
I recently took a car for mapping on behalf of someone else and noticed that the oil pressure was very slow to reach full pressure of around 6 bar. This was of some concern to me. The power figure achieved was very poor, 336 bhp using a turbo that had produced 392 bhp and the mods on both cars were similar. The car was fitted with oil pressure and oil temperature and the oil temperature never exceeded 55C all the time I was in the car. Anyway, on return home I suddenly noticed there was no oil pressure and stopped immediately and waited for several hours for the recovery flatbed.
On checking the car the following day I concluded it was very unlikely there was no oil pressure and after investigation and the use of an alternative guage I found the fault actually lay with the guage or sender unit but pressure was still very lazy to rise taking perhaps 10 seconds plus from cold to reach normal pressure on tick over. On further investigation the car had an adaptor plate where the OE oil filter is located and the filter was now relocated in the inner wing so there was a considerable length of additional oil feed and return pipe.
Further investigation showed the car had mega leak downs but the sandwich plate was removed and the oil system put back to original with the oil filter where it was supposed to be. Full oil pressure is now achieved a few seconds from turning the key but unfortunately the engine has been removed from the car as it had mega leak downs on test and now needs a rebuild.
I come across numerous Classics with aftermarket oil filters and these are just not required on most of them but the owners misguidedly fit oil coolers without first checking what actual temperatures their oil achieves. Typically Classic's will run around 80C or a bit more on oil temperature and in similar conditions New Age are generally 10 degrees or a little more as are all 2.5s. The oil manufacturers advise that the top temperature for their oils is 140 deg.C. which seems high to me but they will know more about oil temperatures than me. On track, I can only remember stopping twice for oil temperature reasons, both on a Classic producing close to 600 bhp on race fuel and I stopped when the oil temperatures reached 125 C. Both occasions were on very hot Summer days, once the hottest day of the Summer actually.
Now if you look in some VW, Audi or Porsche you will see they have oil temperature guages as standard and the red line is at 140C.

Running low oil temperatures greatly shortens the life of the engine just as poor pressure or lubrication on start up will do and I note that Castrol claim that 75% of engine wear takes place on start up.

 

Very, very pertinent and a good cautionary tale Harvey.

It'd be interesting to find out how many people, as you say, are actually looking at the performance of their cars in the real world and genuinely analysing the need for modifications before they're made rather than simply throwing bits on because they look good, or because of some simplistic and incomplete theory, without properly considering the domino effects that those modifications have elsewhere in the system.

This is a perfect case in point where someone working on the (flawed) basis that "colder oil must be better" introduces parts that are on one level simply unnecessary, and on another, potentially cause problems in another area. In the example you're quoting it's easily possible that any benefit provided by the oil cooler will be more than lost via the increased risk of damage to the engine via running under-pressure at light-up, along with colder than optimal oil temps.

Where the oil system has been modified in the manner you're talking about, IMO the increase in the volume of the oil system after the pump should be reflected at least in altering the car's behaviour during start so that light-up is (further) delayed.

The ideal way would be to make the ECU fully aware of oil pressure (or, at very least, feed it the output from a suitably set narrowband pressure switch) and thus programmatically inhibit startup until a predetermined "acceptable" level has been reached. Similarly if the ECU monitors pressure on an ongoing basis during run it's a simple task to institute an emergency shutdown in the event of a drop - which could have saved at least one poster on this board an engine rebuild.

In fact that's so simple I'm amazed Subaru don't actually do it on their series production engines. Cost/benefit analysis I suppose.

Quite.

 

The manufacturers will not inhibit starting until there is some oil pressure simply because people are conditioned to expect the car to start instantly.
I doubt the manufacturer will consider some form of ECU cut out for low oil pressure because there will be very few vehicles that are covered under warranty for such an eventuality. No oil in the sump is down to the owner and most cars that suffer bearing failure will be long out of warranty.
Both ideas could be implemented easily but we are specialist users and not in sufficient number to make it ever happen.

 

THE END - Many Many thanks to the guys that actualy know what theyre on about ;-)
This post is quite a simple guide that can only help you all, it cant hurt by doing it but its obviously too much for some of the numptys to take in

As for some of you "mensioning noooo names" you should never be let near a car or even a spanner to be honest

Take the advise given as im one of the many people that had a perfect running low milage scooby go t1ts up after a service,

So all in all if ya dont need advise or have no advice to give dont read n post absolute cr@p

Many Thanks to SplitPin - Api Dave - Joz8968 - etc etc

 

Fill up the oil filter, everything would be fine.( don't leave home if you scare of being run down by a car)

 

Are you trying to re-light the fuse, here?

JohnD

 

 

i think this oil change situation is all a bit silly to be fair!! it will take 5 mins for all the oil in your engine to reach the sump after switching off the ignition. so idealy everyday before you start up the car on a morning you should disconnect your crank sensor to stop causing damage. what a load of rubbish if your using a good quality in your motor you will have no problems at all, it has been proven by the likes of castrol and shell that a good oil will leave a coating on a bearing surface or engine part which can then be ran dry of oil for a short period of time with out causing damage. a cheap oil flush ran inside the engine before a oil change is the most common cause of bearing failures due to it stripping of this coating with its so called cleaning properties!!!!

 

Bw, read through the thread and your question re the oil film will be answered, as far as cranking the engine AFTER an oil/filter change. An oil/filter CHANGE creates a different condition in the engine, compared to just letting the oil drain down after switch off.

As said, read API's and Splitpin's posts and you'll find out why......

 

What about the airlock introduced after replacing the oil filter?

 

Yawn.

Snore.

RTFTBP

 

FFS if you don't know what you are talking about shut up and listen. OR AT LEAST be bothered to read the explanation some way back about why you are so WRONG.

 

I just think he wants to stretch this thread out to the magic 250 posts . . . !

 

You bloomin' started it

David