my dry startup experiment

[The motor guy]

I decided to see how fast my 350 sbc in my boat would build oil pressure compared to putting the oil filter on dry. The engine has a remote oil filter, so it's upside down in the spot they chose to mount it for whatever reason. I guess they were trying to make things more compact. So looking at the oil pressure gauge, the engine oil was literally almost up to pressure as soon as it fired. Keep in mind, the engine cranks for about 3 seconds before it actually starts. Now after doing an oil change and installing the oil filter dry because I can't really pre fill it upside down. Technically, I could have poured just enough enough oil in to saturate the media, but didn't even do that. This time the engine started, and the oil pressured bliped up and down a few times up to like 20psi, then after about 7 seconds it finally went to full psi which was like 70psi on the gauge. Quite a difference in my opinion for it to actually run for 7 seconds compared to building nearly full pressure while cranking. Nothing that's going to cause a problem I don't think. Anyways, those are my findings. Thought i'd share. Just fyi, this is a MPI engine, so it starts in one try with a turn of the key. No pumping the gas, nothing like that.

 

[ZeeOSix]

Building oil pressure sooner than later is better than not.

Related:

Thread 'Freedom Worx ... video about pre-filling filters'

Jan 2, 2025

There's a new YT vid from Freedom Worx regarding pre-filling oil filters. "The TRUTH about PRE-FILLING oil filters ... ACTUAL SCIENCE" is the title
I won't link it, you'll have to go to YT and find it yourself; there are some elements (profanity and sexual innuendo) which violate our policies; so viewer discretion advised ...

While his approach is admittedly "garage science", it's most certainly entertaining and reasonably well produced. It's 40 minutes long, and yet I don't find myself exhausted as if I had watched LSJr or SK. This guy injects enough sly humor into his...

• dnewton3
• Replies: 112
• Forum: Engine Oil Filters

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• 

 

[The motor guy]

Building oil pressure sooner than later is better than not.

Related:

Thread 'Freedom Worx ... video about pre-filling filters'

Jan 2, 2025

There's a new YT vid from Freedom Worx regarding pre-filling oil filters. "The TRUTH about PRE-FILLING oil filters ... ACTUAL SCIENCE" is the title
I won't link it, you'll have to go to YT and find it yourself; there are some elements (profanity and sexual innuendo) which violate our policies; so viewer discretion advised ...

While his approach is admittedly "garage science", it's most certainly entertaining and reasonably well produced. It's 40 minutes long, and yet I don't find myself exhausted as if I had watched LSJr or SK. This guy injects enough sly humor into his...

• dnewton3
• Replies: 112
• Forum: Engine Oil Filters

• 
• 

Im sure it has plenty of oil slinging around for those 7 seconds. It's just a splash lubricated engine for a second lol

 

[Lawnman23]

That's about the same for my 98 if I don't prefill the filter as much as possible, being mounted horizontally on mine.

 

[The motor guy]

That's about the same for my 98 if I don't prefill the filter as much as possible, being mounted horizontally on mine.

I actually didn't thing it would take as long as it did. Probably won't be trying that again. I always thought it really didn't make much of a difference

 

[Gyro Gearloose]

Im sure it has plenty of oil slinging around for those 7 seconds. It's just a splash lubricated engine for a second lol

That is half of my reasoning for changing oil on a warm engine - there is still the maximum amount of oil left hanging around for the dry start.

 

[ZeeOSix]

Im sure it has plenty of oil slinging around for those 7 seconds. It's just a splash lubricated engine for a second lol

Many parts in an auto engine are force fed by the oil pump. The sooner oil gets to them, the better. If oil pressure took 2 sec vs 7 sec, I'd pick 2 sec.

 

[Kira]

it's upside down in the spot they chose

Doesn't that create a huge mess upon removal?

 

[Trav]

Im sure it has plenty of oil slinging around for those 7 seconds. It's just a splash lubricated engine for a second lol

Unlike small OPE engine that use "dippers" that reach down into the sump to grab oil and sling it auto engines use some sort of windage tray either separate or integrated into the gasket to prevent this, the crank is not running in the oil.

What does an oil pan windage tray do?

A windage tray normally separates the crank from the pan sump almost completely. It allows what drains into the pan to access the sump (either through shaped louvers or a screen), but makes it difficult for that oil, once it is in the sump, to splash back onto the crank

A common style oil pan gasket/windage tray.

 

[dnewton3]

Many parts in an auto engine are force fed by the oil pump. The sooner oil gets to them, the better. If oil pressure took 2 sec vs 7 sec, I'd pick 2 sec.

If I understand the OPs situation, the bulk of his delay is probably because after a good OCI drain, the remote filter mount location creates the unusually long "dry" start. The filter is not in a position to prefill, and so the delay can't really be altered.

I agree that less time w/o pressure is better, but in this case, he really doesn't have a choice to shorten the time delay, unless he gets a pre-charge system installed.

 

[Fair enough]

I don’t know if a faulty or missing bypass valve in the block would have anything to do with it? You say normally it’s fine. The oil filter can’t be put back to the correct location on the block?
This would be a perfect candidate for a Frantz oil filter using the full flow adapter if an oil filter can’t be put on the block. They make a synthetic 2 micron filter and a regular which is even finer at filtering. It would replace the thing someone put in. Amsoil may have something too, they make remote kits.
Frantz has a video, maybe too much for advertising here, where oil is cleaned better after using a full flow filter.

 

[ZeeOSix]

I actually didn't thing it would take as long as it did. Probably won't be trying that again. I always thought it really didn't make much of a difference

If you can't pre-fill the filter then isn't it going to be doing that again every time you change the oil filter. Or do you normally try to pre-fill enough to get all the media soaked, but this time you did a bone dry filter install?

 

[The motor guy]

If you can't pre-fill the filter then isn't it going to be doing that again every time you change the oil filter. Or do you normally try to pre-fill enough to get all the media soaked, but this time you did a bone dry filter install?

I've found you can put a good amount of oil into the filter that the media will soak up and still be able to turn the filter horizontally or upside down. I just didn't bother putting any in this time to see what would happen. You are correct, this isn't an every time event, but I do wonder how long the engine will run before it shuts off. I'm pretty sure if the ecm doesn't see oil pressure it will shut off. Or shut the fuel pump off, one of the two.

 

[sdowney717]

Unlike small OPE engine that use "dippers" that reach down into the sump to grab oil and sling it auto engines use some sort of windage tray either separate or integrated into the gasket to prevent this, the crank is not running in the oil.

What does an oil pan windage tray do?

A common style oil pan gasket/windage tray.

View attachment 262394

Windage tray reduces parasitic loss caused by oil mist around a crank. I imagine high revving motors benefit more.

When the engine is running, the crankshaft rotates rapidly, causing the oil in the oil pan to churn and create an oil mist. This churning effect, known as windage, can create a drag on the crankshaft, leading to a decrease in engine efficiency and power.

That’s where the windage tray comes in. It is strategically placed between the spinning crankshaft and the oil in the oil pan. The tray’s perforated design allows oil splashed upwards by the crankshaft’s rotation to drain back down into the oil pan. Simultaneously, it serves as a shield, preventing the swirling oil mist from coming into contact with the crankshaft. This separation significantly reduces the parasitic power loss due to windage.

Moreover, by ensuring that the oil quickly drains back to the oil pan, the windage tray aids in maintaining an optimal oil supply to the engine components, promoting their smooth operation and longevity.

https://carnewscast.com/windage-trays-everything-you-need-to-know/

 

[The motor guy]

The crankshaft is filled with oil. It's going to sling oil around as it's spinning

 

[tmorris1]

Isn't this essential what "Lake the Oil Geek" found in one of his videos?

 

[ZeeOSix]

That’s where the windage tray comes in. It is strategically placed between the spinning crankshaft and the oil in the oil pan. The tray’s perforated design allows oil splashed upwards by the crankshaft’s rotation to drain back down into the oil pan.

There's a lot of oil mist and oil droplets flying around due to all the rod and crank bearing's side leakage exiting them as the crank spins ... the higher the RPM, the higher the bearing side leakage and the more oil mist/droplets flying around. The perforations in the windage tray are to let all the bearing side leakage oil drain back to the oil pan.

 

[sdowney717]

The crankshaft is filled with oil. It's going to sling oil around as it's spinning

Something about an oil mist forming around the crank without a windage try

 

[The motor guy]

I wonder why we can't have fuel systems thst reprime as fast as oil pumps do?