Changing your oil
Road Captain
Joined: Dec 2005
Posts: 716
Likes: 5
From: Harley Home
RE: Changing your oil
Let me get this straight................if you don't use the puck then you will contaminate the filter? I may be wrong but doesn't the oil flow through the filter to the engine? So if you use a puck the contaminated engine oil doesn't filtered it goes to the engine?
Road Captain
Joined: Nov 2005
Posts: 720
Likes: 6
RE: Changing your oil
Yeah, the problem is, that your contaminating that new oil filter with the old oil passing through it. The majority of the leftover oil in the engine sits in the camchest and crank sump which will pass through the oil filter.
Banned
Joined: Nov 2005
Posts: 802
Likes: 3
From:
RE: Changing your oil
ORIGINAL: daboys53119
Let me get this straight................if you don't use the puck then you will contaminate the filter? I may be wrong but doesn't the oil flow through the filter to the engine? So if you use a puck the contaminated engine oil doesn't filtered it goes to the engine?
Let me get this straight................if you don't use the puck then you will contaminate the filter? I may be wrong but doesn't the oil flow through the filter to the engine? So if you use a puck the contaminated engine oil doesn't filtered it goes to the engine?
So yes, if your putting on a fresh oil filter and then "flushing" your engine, you essentially running about a quart of dirty oil through it before clean oil ever hits it.
We used to "gut" a couple oil filters(cut out and remove the filter element inside) and use them as a generic bypass, but it would cause a mess since it held a good amount of oil. The wholesale cost of the scavenger for us was more than worth the investment just from less waste(probably 3-4 quarts worth every week which adds up to a good amount of $$$ even at wholesale cost over time) of good clean oil being mopped up and wasted at every oil change.
Banned
Joined: Nov 2005
Posts: 802
Likes: 3
From:
RE: Changing your oil
ORIGINAL: peppi
Well look at it this way, when you start up the filter is usually in bypass mode because of the viscosity of the oil when it's cold, especially with the new 5 micron and besides the majority of the "OLD" oil is in the return side (scavenge) side of the sump (after the filter) thereby emptying it out at start up through the drain hose by pushing the new oil into the system.It's your money and if it makes you feel better, then do it with the puck, me? I'll stick with my way. $60 just so it looks cool isn't for me.The small amount of dirty oil that may go through the filter media itself probably couldn't even be measured.
Yeah, the problem is, that your contaminating that new oil filter with the old oil passing through it. The majority of the leftover oil in the engine sits in the camchest and crank sump which will pass through the oil filter.
Some people dont mind spending the money, some people such as yourself do mind. Who cares. Its a good little tool to have in the kit for the DIYer, and many will find it very useful for keeping to contaminents to an absolute minimum in their engine. I know plenty of people who love their scavenger and feel its worth every penny, Im one of em(for commercial and personal reasons) I can garentee it pays for itself over over time, even for the DIY end user with just one bike.
Road Captain
Joined: Nov 2005
Posts: 720
Likes: 6
RE: Changing your oil
Here's the flow of the oil
In the TC engines ,the oil goes from the oil tank to the pump, to the filter to the engine to the crankcase to the scaveng sump and back to the oil tank
You say it would cause a mess, by doing this you are essentially running an open filter and starving the engine of oil doing it this way. Not a recommended way of doing it at all.
I don't mind spending money on something that works ,that's what it 's all about, but to just buy a product such as this doesn't make any sense to me at all because it looks impressive.
I can't agree with your theory at all.
In the TC engines ,the oil goes from the oil tank to the pump, to the filter to the engine to the crankcase to the scaveng sump and back to the oil tank
We used to "gut" a couple oil filters(cut out and remove the filter element inside) and use them as a generic bypass, but it would cause a mess since it held a good amount of oil.
I don't mind spending money on something that works ,that's what it 's all about, but to just buy a product such as this doesn't make any sense to me at all because it looks impressive.
The old oil with go through the new filter element FULLY
Banned
Joined: Nov 2005
Posts: 802
Likes: 3
From:
RE: Changing your oil
ORIGINAL: peppi
Here's the flow of the oil
In the TC engines ,the oil goes from the oil tank to the pump, to the filter to the engine to the crankcase to the scaveng sump and back to the oil tank
You say it would cause a mess, by doing this you are essentially running an open filter and starving the engine of oil doing it this way. Not a recommended way of doing it at all.
Here's the flow of the oil
In the TC engines ,the oil goes from the oil tank to the pump, to the filter to the engine to the crankcase to the scaveng sump and back to the oil tank
We used to "gut" a couple oil filters(cut out and remove the filter element inside) and use them as a generic bypass, but it would cause a mess since it held a good amount of oil.
And the scavenger itself only holds a few cc's worth of oil(hence bypass)in its bypass passage. It feeds the engine immediately.
If you honestly had a good understanding of the twin cam oiling system, you would know that every day when you start up your engine, the oil pump takes a few seconds to fill and pressurize your oil filter before oil is feed back through the camplate and to the engine. Those little rubber bypass flaps in the oil filters are only good at keeping oil from seeping back down into the camchest foran hour or 2. Oil slowly leaks past them and your oil filter partially empties out overnight.
Road Captain
Joined: Nov 2005
Posts: 720
Likes: 6
RE: Changing your oil
The gutted oil filter is full and feeding oil to the rest of the engine within a few seconds of startup, the engine is already full of stationary oil throughtout the crank assembly and valvetrain.
Banned
Joined: Nov 2005
Posts: 802
Likes: 3
From:
RE: Changing your oil
ORIGINAL: peppi
I don't mind spending money on something that works ,that's what it 's all about, but to just buy a product such as this doesn't make any sense to me at all because it looks impressive.
I can't agree with your theory at all.
I don't mind spending money on something that works ,that's what it 's all about, but to just buy a product such as this doesn't make any sense to me at all because it looks impressive.
The old oil with go through the new filter element FULLY
Thats fine, you don't have to. I already know for a FACT it does. A clean filter element with no backside pressure(since its empty with NO oil) will allow all the oil to flow through the filter element, none is going to go around it whether hot or cold, even on an "high efficiency" 5 micron filter. It takes serious pressure to open that bypass valve, and it will only open when the filter is really clogged with an excessive amount of unequal pressure between the frontside and backside of the filter element(ie: a 10 psi bypass filter will require a difference of 10psi between both sides of the filter to activate). And the larger the surface area is on the filter element, the longer it will take for the bypass filter to activate since bleedthrough will be greater.
The only time that bypass filter will open on your oil filter is when the filter its getting clogged up when the engine is running at high rpms when the pressure from the pump is greatest. At idle the pump puts out low pressure and relatively low oil volume.
HD Forum Stories
The Best of Harley-Davidson for Lifelong Riders
7 Surprising Harley-Davidson Products that Are Not Motorcycles
Verdad Gallardo
8 Best Harley-Davidson Motorcycles Ever
Pouria Savadkouei
10 Worst Harley-Davidson Motorcycles Ever
Pouria Savadkouei
Killer Custom's Jail Break Is The Breakout That Refused to Blend In
Verdad Gallardo
Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?
Verdad Gallardo
Harley-Davidson Reveals Super Cool Cafe Racer Concept
Verdad Gallardo
Engraved Rebellion: Inside Bundnerbike's Glam Rock II
Verdad Gallardo
10 Motorcycles You Should Never Buy
Joe Kucinski
10 Things Harley-Davidson Needs to Fix in 2026
Verdad Gallardo
Banned
Joined: Nov 2005
Posts: 802
Likes: 3
From:
RE: Changing your oil
ORIGINAL: peppi
This oil you speak of is after the filter in any event, and the total of the old oil left in the engine is less than a quart, most of which is after the filter to start with so it wouldn't be passing through the filter as I said before.And I have a very good understanding of oiling systems and the benefits of using this device if there are any.There are people who can see the benefits if any of different products without endorsing a product that are not clear here. This is arguing a mute point.
The gutted oil filter is full and feeding oil to the rest of the engine within a few seconds of startup, the engine is already full of stationary oil throughtout the crank assembly and valvetrain.
The rest comes from the feed gerotor from the oil bag. There is about a quart of dirty oil left in the twin cam. I get about 28-30 ounces on average. About 18-20 oz alone are from the cam chest and crank sump.All you gotta do is this simple test for yourself. Stick a fresh oil filter on your engine during your next oil change,pull the return line from your oil bag so you can flush the old oil out, crank the engine over, wait a few seconds, when you start to get old oil pouring out, shut the engine down, pull that oil filter off and inspect it, your not going to find any clean oil in it. And all you gotta do is check inside the middle(engine return side) and you will see it filled with old oil.
And, like I said above a few past posts, some DIY people will appreciate the tool and find it well worth the few extra bucks, some won't, who cares?
Road Captain
Joined: Nov 2005
Posts: 720
Likes: 6
RE: Changing your oil
Again, you dont understand the plumbing of the TC oil system or you wouldnt be continuing this.
I think you should rethink a few things you posted here and come up with a better mousetrap so to speak. Some of your theories are rather soggy.
As far as the DIY people appreciating the tool, that's fine , I have no problem with that at all.
Now for your theory about the new filter, this is old news to me and I have explored many facets of oiling systems probably before it was even thought of. There is more than one person in the world that can analize a situation and come up with a conclusion that benefits most people.