View Poll Results: How I change my oil
I warm the car up and make the change while still warm
40
78.43%
i just change it cold
10
19.61%
i let the shop do it
1
1.96%
Voters: 51. You may not vote on this poll
OIL CHANGE TECHNQUE - Hot or cold?
07-13-2018, 04:18 PM
#32
Rennlist Member
As the engine crankcase is designed to not hold oil at the top end (longer than neccessary to feed the components) and lets it drain back to the pan as soon as possible after its circuit, I run the engine to hot for the splash in the oil pan to put as much of the particulate matter (that bypasses the filter) in solution (instead of settling and clinging to the bottom of a cold pan). The thinned oil will quickly drain from the internal surfaces AND take as much of that particulate with it. The engine block is a heat sink in this scenario and will help keep the oil thinned until it fully drains out.
Let the pan drain until it stops dripping, clean your magnetic plug and refill the filter and crankcase.
Whats the to-do about crush washers? In the 21 years I have had this 928, it has had the same crush washer and does not drip a drop.
Let the pan drain until it stops dripping, clean your magnetic plug and refill the filter and crankcase.
Whats the to-do about crush washers? In the 21 years I have had this 928, it has had the same crush washer and does not drip a drop.
07-13-2018, 07:09 PM
#33
Rennlist Member
Thread Starter
As the engine crankcase is designed to not hold oil at the top end (longer than neccessary to feed the components) and lets it drain back to the pan as soon as possible after its circuit, I run the engine to hot for the splash in the oil pan to put as much of the particulate matter (that bypasses the filter) in solution (instead of settling and clinging to the bottom of a cold pan). The thinned oil will quickly drain from the internal surfaces AND take as much of that particulate with it. The engine block is a heat sink in this scenario and will help keep the oil thinned until it fully drains out.
Let the pan drain until it stops dripping, clean your magnetic plug and refill the filter and crankcase.
Whats the to-do about crush washers? In the 21 years I have had this 928, it has had the same crush washer and does not drip a drop.
Let the pan drain until it stops dripping, clean your magnetic plug and refill the filter and crankcase.
Whats the to-do about crush washers? In the 21 years I have had this 928, it has had the same crush washer and does not drip a drop.
I just thought i deserved a new crush washer... best 2 dollars ive spent in years for that piece of mind! 
07-13-2018, 07:37 PM
#34
07-13-2018, 09:46 PM
#35
Rennlist Member
I did not say to drain for 5 minutes and it actually takes a lot longer than 5 minutes to stop dripping. Of course you put the passenger wheel on a higher block for the tilt.
07-13-2018, 11:18 PM
#36
Rennlist Member
07-14-2018, 02:55 PM
#37
Rennlist
Basic Site Sponsor
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The design of that valve leaves several millimeters of oil in the pan, versus the stock plug....like 3-4 millimeters.
Additionally, the stock plug has a magnet, which is a great addition.
I remove and re-install those drain valves to change oil, if the current owner added it on.
On cars where the current owner didn't install them, I remove them, throw them away, and put in the correct drain plug.
07-14-2018, 06:46 PM
#38
Rennlist Member
Thread Starter
I'm not one of the cool kids....
The design of that valve leaves several millimeters of oil in the pan, versus the stock plug....like 3-4 millimeters.
Additionally, the stock plug has a magnet, which is a great addition.
I remove and re-install those drain valves to change oil, if the current owner added it on.
On cars where the current owner didn't install them, I remove them, throw them away, and put in the correct drain plug.
The design of that valve leaves several millimeters of oil in the pan, versus the stock plug....like 3-4 millimeters.
Additionally, the stock plug has a magnet, which is a great addition.
I remove and re-install those drain valves to change oil, if the current owner added it on.
On cars where the current owner didn't install them, I remove them, throw them away, and put in the correct drain plug.
07-15-2018, 01:27 AM
#40
Rennlist Member
Thread Starter
1. jack up the driver side and loosen the drain plug.
2 crack the filter and with the drain pan... the one that seal up with a cover and remove the filter allowing the oil to drain into the pan.
3. replace filter with pre-filled filter and tighten.
4. loosen drain plug by hand all the way to the very end (or use a rachet open end 15mm)
5. lift the oil capture pan up with right hand making the pan very close to the drain plug
6. remove drain plug and as the flow goes into pan, slowly lower it following the flow -arc as it moves near directly straight down..
7. jack car down and wait 5 mns for the oil to drain as best as possible. (cold or warm)
8. jack car back up, replace drain plug and remove oil pan that should be on a wide piece of cardboard.
9. torque drain plug
10 fill with oil using gallon jugs with no funnel (there is room to do this pretty easily)
the key technique is to lift the oil pan up to the drain hole when the plug is removed.. this way, hot or cold, it reduces the chance of missing the pan and you control the flow easily
07-15-2018, 11:50 AM
#41
Rennlist Member
I'm not one of the cool kids....
The design of that valve leaves several millimeters of oil in the pan, versus the stock plug....like 3-4 millimeters.
Additionally, the stock plug has a magnet, which is a great addition.
I remove and re-install those drain valves to change oil, if the current owner added it on.
On cars where the current owner didn't install them, I remove them, throw them away, and put in the correct drain plug.
The design of that valve leaves several millimeters of oil in the pan, versus the stock plug....like 3-4 millimeters.
Additionally, the stock plug has a magnet, which is a great addition.
I remove and re-install those drain valves to change oil, if the current owner added it on.
On cars where the current owner didn't install them, I remove them, throw them away, and put in the correct drain plug.
I also see your point on the drain plug magnet. With your business you don't have the luxury of sending oil for analysis every time and looking at the magnet gives a quick indicator if there's trouble brewing. Personally I change my oil once a year and send a pee-cup to Blackstone. BTW - Blackstone has a short paper on drain plug magnets. Here's their conclusion:
"Are there any downsides to using magnets? Probably not, though I did read an interesting debate on a forum where one guy claimed that any metal that might break free of the magnet or pass over the magnet without getting captured could, in turn, become magnetic and then proceed to stick to other internal iron parts. What you would then have is tiny shards of metal attached to operating parts, which doesn’t seem healthy. Of course, that’s all a bit speculative for my taste, but maybe there are others reading this who are smarter than me who might take a crack at proving or disproving that hypothesis.
These findings do help answer one question that we get a lot—will using a magnetic drain plug throw off my oil analysis results? From what my tests show, the answer is maybe. It depends on the engine. Keep in mind that a magnet only affects iron, so it won’t change any of the other metals. If you do decide to use a magnetic drain plug, use it consistently. That way, you’ll still have a level playing field when looking at wear trends and be able to see if wear at steel parts is holding steady or not.
So, should you spend your own hard-earned money on one of these drain plugs? There is not enough evidence here for me to recommend their use. But they shouldn’t hurt anything either and if it helps you sleep better at night, then go for it. They might be useful in assessing wear at steel parts. The more metal on the plug, the more metal the engine is making. But if you really want to see what’s going on in the engine, you still can’t beat following an oil analysis regimen. Since that’s the case, you might as well do it with us. After all, we love you enough to do experiments that don’t really tell you anything for certain. Where else are you going to get that kind of service
Sauce: https://www.blackstone-labs.com/News...rch-1-2013.php
As far as your customer base, if a customer put one on, they're not going to bring it to you for an oil change.
07-15-2018, 05:49 PM
#42
Rennlist Member
Thread Starter
got it. i didnt understand how far it would extend down... so the main issue i have is the smaller hole, and length of time of drainage. plus the magnetic plug, and no, things that pass by wont be magnatized to any extent. its a good idea, but its hard to see a use in my process. the flow rate alone is the reason for me, as well as trapping a cup of oil more as welll no belly pans on the 928. part of my cooling system! and the car is too low for it.
Mk
and the car is too low for it.Mk
Hi Greg - I don't have an oil pan to measure but assuming the lower area is 10"x12" and the valve leaves 3 mm (.118") the surface area would be ~6oz of oil. I tilt the car towards the drain plug so the math would be different and the amount of oil "missed" would be less. But I concede that the neck of the valve that threads into the pan would prevent a measurable amount to not drain. An amount to care about? I dunno.
I also see your point on the drain plug magnet. With your business you don't have the luxury of sending oil for analysis every time and looking at the magnet gives a quick indicator if there's trouble brewing. Personally I change my oil once a year and send a pee-cup to Blackstone. BTW - Blackstone has a short paper on drain plug magnets. Here's their conclusion:
"Are there any downsides to using magnets? Probably not, though I did read an interesting debate on a forum where one guy claimed that any metal that might break free of the magnet or pass over the magnet without getting captured could, in turn, become magnetic and then proceed to stick to other internal iron parts. What you would then have is tiny shards of metal attached to operating parts, which doesn’t seem healthy. Of course, that’s all a bit speculative for my taste, but maybe there are others reading this who are smarter than me who might take a crack at proving or disproving that hypothesis.
These findings do help answer one question that we get a lot—will using a magnetic drain plug throw off my oil analysis results? From what my tests show, the answer is maybe. It depends on the engine. Keep in mind that a magnet only affects iron, so it won’t change any of the other metals. If you do decide to use a magnetic drain plug, use it consistently. That way, you’ll still have a level playing field when looking at wear trends and be able to see if wear at steel parts is holding steady or not.
So, should you spend your own hard-earned money on one of these drain plugs? There is not enough evidence here for me to recommend their use. But they shouldn’t hurt anything either and if it helps you sleep better at night, then go for it. They might be useful in assessing wear at steel parts. The more metal on the plug, the more metal the engine is making. But if you really want to see what’s going on in the engine, you still can’t beat following an oil analysis regimen. Since that’s the case, you might as well do it with us. After all, we love you enough to do experiments that don’t really tell you anything for certain. Where else are you going to get that kind of service
Sauce: https://www.blackstone-labs.com/News...rch-1-2013.php
As far as your customer base, if a customer put one on, they're not going to bring it to you for an oil change.
As you can see in the photo, they don't extend below the drain pan. If a piece of debris was to fly up there I'd be more concerned about it busting off the sensor than a 3/4" drain plug. I also noticed in your post below that you don't mention belly pan removal - do you not have them installed? They too would mitigate debris getting up there.
I also see your point on the drain plug magnet. With your business you don't have the luxury of sending oil for analysis every time and looking at the magnet gives a quick indicator if there's trouble brewing. Personally I change my oil once a year and send a pee-cup to Blackstone. BTW - Blackstone has a short paper on drain plug magnets. Here's their conclusion:
"Are there any downsides to using magnets? Probably not, though I did read an interesting debate on a forum where one guy claimed that any metal that might break free of the magnet or pass over the magnet without getting captured could, in turn, become magnetic and then proceed to stick to other internal iron parts. What you would then have is tiny shards of metal attached to operating parts, which doesn’t seem healthy. Of course, that’s all a bit speculative for my taste, but maybe there are others reading this who are smarter than me who might take a crack at proving or disproving that hypothesis.
These findings do help answer one question that we get a lot—will using a magnetic drain plug throw off my oil analysis results? From what my tests show, the answer is maybe. It depends on the engine. Keep in mind that a magnet only affects iron, so it won’t change any of the other metals. If you do decide to use a magnetic drain plug, use it consistently. That way, you’ll still have a level playing field when looking at wear trends and be able to see if wear at steel parts is holding steady or not.
So, should you spend your own hard-earned money on one of these drain plugs? There is not enough evidence here for me to recommend their use. But they shouldn’t hurt anything either and if it helps you sleep better at night, then go for it. They might be useful in assessing wear at steel parts. The more metal on the plug, the more metal the engine is making. But if you really want to see what’s going on in the engine, you still can’t beat following an oil analysis regimen. Since that’s the case, you might as well do it with us. After all, we love you enough to do experiments that don’t really tell you anything for certain. Where else are you going to get that kind of service
Sauce: https://www.blackstone-labs.com/News...rch-1-2013.php
As far as your customer base, if a customer put one on, they're not going to bring it to you for an oil change.
As you can see in the photo, they don't extend below the drain pan. If a piece of debris was to fly up there I'd be more concerned about it busting off the sensor than a 3/4" drain plug. I also noticed in your post below that you don't mention belly pan removal - do you not have them installed? They too would mitigate debris getting up there.
07-15-2018, 06:06 PM
#43
Rennlist Member
I guess I'm one of those few that "let's the shop do it"...but in this case its for the convenience of disposing of very hot engine oil..I think changing the oil is best when the oil is hot and the car has been running for a while.
That being said..I'm not wealthy and have money to throw away; but I abhor being environmentally irresponsible with things like engine oil when we all know better...plus I'm lazy and don't want to drag used engine oil somewhere else to get it disposed of properly
I work with a single shop that knows how to use a torque wrench...yes they are a Valvoline Quick Oil change or whatever they're called..they know my car... I provide a filter (I re-new with Roger each time) that includes a crush washer and it gets done every $5k or annually just before spring...not a big deal.
But to me the oil is good and hot when changed.
That being said..I'm not wealthy and have money to throw away; but I abhor being environmentally irresponsible with things like engine oil when we all know better...plus I'm lazy and don't want to drag used engine oil somewhere else to get it disposed of properly
I work with a single shop that knows how to use a torque wrench...yes they are a Valvoline Quick Oil change or whatever they're called..they know my car... I provide a filter (I re-new with Roger each time) that includes a crush washer and it gets done every $5k or annually just before spring...not a big deal.
But to me the oil is good and hot when changed.
07-15-2018, 06:12 PM
#44
Rennlist Member
What i do , is
1. jack up the driver side and loosen the drain plug.
2 crack the filter and with the drain pan... the one that seal up with a cover and remove the filter allowing the oil to drain into the pan.
3. replace filter with pre-filled filter and tighten.
4. loosen drain plug by hand all the way to the very end (or use a rachet open end 15mm)
5. lift the oil capture pan up with right hand making the pan very close to the drain plug
6. remove drain plug and as the flow goes into pan, slowly lower it following the flow -arc as it moves near directly straight down..
7. jack car down and wait 5 mns for the oil to drain as best as possible. (cold or warm)
8. jack car back up, replace drain plug and remove oil pan that should be on a wide piece of cardboard.
9. torque drain plug
10 fill with oil using gallon jugs with no funnel (there is room to do this pretty easily)
the key technique is to lift the oil pan up to the drain hole when the plug is removed.. this way, hot or cold, it reduces the chance of missing the pan and you control the flow easily
1. jack up the driver side and loosen the drain plug.
2 crack the filter and with the drain pan... the one that seal up with a cover and remove the filter allowing the oil to drain into the pan.
3. replace filter with pre-filled filter and tighten.
4. loosen drain plug by hand all the way to the very end (or use a rachet open end 15mm)
5. lift the oil capture pan up with right hand making the pan very close to the drain plug
6. remove drain plug and as the flow goes into pan, slowly lower it following the flow -arc as it moves near directly straight down..
7. jack car down and wait 5 mns for the oil to drain as best as possible. (cold or warm)
8. jack car back up, replace drain plug and remove oil pan that should be on a wide piece of cardboard.
9. torque drain plug
10 fill with oil using gallon jugs with no funnel (there is room to do this pretty easily)
the key technique is to lift the oil pan up to the drain hole when the plug is removed.. this way, hot or cold, it reduces the chance of missing the pan and you control the flow easily
07-15-2018, 06:23 PM
#45
Rennlist Member
Thread Starter
But if you jack up the drivers side ( and unload the suspension on that side) when you drop the car back down, the drain plug is no longer the lowest point of the pan due to the drivers wheel now being lower in the fender due to the need for that side to settle again. You would clearly have residual oil in the passenger side of the pan and draining it for only five minutes isn t sufficient. Do you drain hot or cold?